CN110012553B

CN110012553B - Session control method, network device and terminal

Info

Publication number: CN110012553B
Application number: CN201810009027.5A
Authority: CN
Inventors: 柯小婉
Original assignee: Vivo Mobile Communication Co Ltd
Current assignee: Vivo Mobile Communication Co Ltd
Priority date: 2018-01-04
Filing date: 2018-01-04
Publication date: 2021-04-20
Anticipated expiration: 2038-01-04
Also published as: WO2019134657A1; CN110012553A

Abstract

The invention discloses a session control method, network equipment and a terminal, wherein the method comprises the following steps: acquiring operation request information of packet data unit PDU session information; and carrying out PDU session processing according to the operation request information. The invention can recover PDU conversation according to requirement when the suspended terminal recovers connection through the cooperation of the terminal, the first network unit and the second network unit, saves resources of wireless access network and reduces signaling cost.

Description

Session control method, network device and terminal

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a session control method, a network device, and a terminal.

Background

Cellular Internet of Things (CIOT) is an optimized method for data transmission, comprising a control panel CIOT and a user plane CIOT. The User plane CIOT refers to a manner of maintaining a context of a terminal in a radio access network by suspending connection between the terminal and a network when the terminal (UE) needs to be released or is inactive. When the terminal needs to restore the connection with the network, the context of the terminal does not need to be established again in the wireless access network. The terminal also can not need to send a service request to the core network, thereby achieving the effects of saving the signaling for establishing the connection and reducing the time delay. The connection between the terminal and the network may refer to Radio Resource Control (RRC) connection between the terminal and an access network, and connection between the access network and a core network related to the terminal.

For a terminal using the user plane CIOT, signaling for connection establishment in a service request process can be saved and time delay can be reduced when connection is resumed, but for a suspended PDU session, especially a suspended PDU session on a Radio Access Network (RAN) side, whether to resume or not and whether to resume a Radio bearer cannot be determined according to the intention of the terminal. If all PDU sessions are restored by default, restoring the PDU sessions that the terminal does not want to restore wastes the radio resources for establishing the radio bearer.

Disclosure of Invention

The embodiment of the invention provides a session control method, network equipment and a terminal, aiming at solving the problems of complex signaling and low infinite resource utilization rate in the PDU session recovery process in a 5G system.

In a first aspect, an embodiment of the present invention provides a session control method, applied to a first network element side, including:

acquiring operation request information of packet data unit PDU session information; the operation request information includes at least one of the following information: PDU session information which is requested to be recovered by a terminal, PDU session information which is requested to be released by the terminal and PDU session information which is requested to be hung by the terminal;

and carrying out PDU session processing according to the operation request information.

In a second aspect, an embodiment of the present invention further provides a network device, applied to a first network element side, including:

the first acquisition module is used for acquiring operation request information of the PDU session information; the operation request information includes at least one of the following information: PDU session information which is requested to be recovered by a terminal, PDU session information which is requested to be released by the terminal and PDU session information which is requested to be hung by the terminal;

and the first processing module is used for carrying out PDU session processing according to the operation request information.

In a third aspect, an embodiment of the present invention provides a session control method, applied to a first network element side, including:

acquiring operation request information of packet data unit PDU session information; the operation request information includes at least one of the following information: the PDU session information which is requested to be recovered by the second network unit, the PDU session information which is requested to be released by the second network unit and the PDU session information which is requested to be suspended by the second network unit;

In a fourth aspect, an embodiment of the present invention further provides a network device, applied to a first network element side, including:

the second acquisition module is used for acquiring the operation request information of the PDU session information; the operation request information includes at least one of the following information: the PDU session information which is requested to be recovered by the second network unit, the PDU session information which is requested to be released by the second network unit and the PDU session information which is requested to be suspended by the second network unit;

and the second processing module is used for carrying out PDU session processing according to the operation request information.

In a fifth aspect, an embodiment of the present invention provides a session control method, applied to a second network element side, including:

acquiring operation request information of packet data unit PDU session information; the operation request information includes at least one of the following information: PDU session information requested to be recovered by the terminal, PDU session information requested to be released by the terminal, PDU session information requested to be suspended by the terminal, PDU session recovery result information of the first network unit, PDU session information requested to be recovered by the third network unit, PDU session information requested to be released by the third network unit, PDU session information requested to be suspended by the third network unit, PDU session information required by downlink data transmission and PDU session information notified by the received downlink data;

In a sixth aspect, an embodiment of the present invention provides a network device, applied to a second network element side, including:

a third obtaining module, configured to obtain operation request information of packet data unit PDU session information; the operation request information includes at least one of the following information: PDU session information requested to be recovered by the terminal, PDU session information requested to be released by the terminal, PDU session information requested to be suspended by the terminal, PDU session recovery result information of the first network unit, PDU session information requested to be recovered by the third network unit, PDU session information requested to be released by the third network unit, PDU session information requested to be suspended by the third network unit, PDU session information required by downlink data transmission and PDU session information notified by the received downlink data;

and the third processing module is used for carrying out PDU session processing according to the operation request information.

In a seventh aspect, an embodiment of the present invention provides a session control method, applied to a terminal side, including:

transmitting operation request information of Packet Data Unit (PDU) session information to a first network element;

receiving PDU conversation operation response information sent by the first network unit according to the operation request information;

and carrying out PDU session processing according to the PDU session operation response information.

In an eighth aspect, an embodiment of the present invention further provides a terminal, including:

a third sending module, configured to send operation request information of packet data unit PDU session information to the first network element;

a second receiving module, configured to receive PDU session operation response information sent by the first network unit according to the operation request information;

and the fourth processing module is used for processing the PDU conversation according to the PDU conversation operation response information.

In a ninth aspect, an embodiment of the present invention provides a network device, where the network device includes a processor, a memory, and a computer program stored in the memory and running on the processor, and the processor implements the steps of the session control method when executing the computer program.

In a tenth aspect, an embodiment of the present invention provides a terminal, where the terminal includes a processor, a memory, and a computer program stored in the memory and being executable on the processor, and the computer program, when executed by the processor, implements the steps of the session control method described above.

In an eleventh aspect, an embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the steps of the session control method described above.

Therefore, the session control method, the network device and the terminal of the embodiment of the invention obtain the operation request information of the PDU session information; and carrying out PDU session processing according to the operation request information. Wherein the operation request information includes at least one of the following information: the terminal requests the PDU session information of restoring, the terminal requests the PDU session information of releasing, the terminal requests the PDU session information of suspending, the second network unit requests the PDU session information of restoring, the second network unit requests the PDU session information of releasing, the second network unit requests the PDU session information of suspending. Therefore, through the mutual cooperation among the terminal, the first network unit and the second network unit, when the connection of the suspended terminal is recovered, the recovery of the PDU session can be carried out according to the PDU session information needing to be recovered in the operation request information, thereby saving the resources of the wireless access network and reducing the signaling overhead.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments of the present invention will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor.

Fig. 1 shows one of the flow diagrams of a session control method of a first network element in an embodiment of the invention;

fig. 2 shows one of the block schematic diagrams of the network device of the first network element in the embodiment of the present invention;

fig. 3 is a second flowchart illustrating a session control method of the first network element according to an embodiment of the present invention;

fig. 4 is a second schematic block diagram of a network device of the first network unit according to the embodiment of the present invention;

fig. 5 is a flow chart illustrating a session control method of a second network element according to an embodiment of the present invention;

fig. 6 is a schematic block diagram of a network device of a second network element according to an embodiment of the present invention;

fig. 7 is a block diagram showing a configuration of a network device in the embodiment of the present invention;

fig. 8 is a flowchart illustrating a session control method of a terminal according to an embodiment of the present invention;

fig. 9 is a schematic block diagram of a terminal according to an embodiment of the present invention;

fig. 10 shows a block diagram of a terminal in an embodiment of the present invention;

FIG. 11 is a schematic diagram of a network architecture according to an embodiment of the present invention;

fig. 12 is a flowchart illustrating a session control method according to a first embodiment of the present invention;

fig. 13 is a flowchart illustrating a session control method according to a second embodiment of the present invention;

fig. 14 is a flowchart illustrating a session control method according to a third embodiment of the present invention;

fig. 15 is a flowchart illustrating a session control method according to a fourth embodiment of the present invention;

fig. 16 is a flowchart illustrating a session control method according to a fifth embodiment of the present invention;

fig. 17 is a flowchart illustrating a session control method according to a sixth embodiment of the present invention;

fig. 18 is a flowchart illustrating a session control method according to a seventh embodiment of the present invention.

Detailed Description

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The embodiment of the invention provides a session control method, which is applied to a first network unit side, wherein the first network unit comprises at least one of the following components: a radio Access network device, a radio Access network node, a radio Access network Function Unit, a Centralized Unit (CU), a Distributed Unit (DU), a base station, an eNB, a gNB, a Non-3GPP InterWorking Function (N3 IWF), an Access Controller (AC) node, an Access Point (AP) device, or a Wireless Local Area Network (WLAN) node; the second network element comprises at least one of: the mobile Management system comprises core network equipment, core network nodes, a core network Function unit, a Mobility Management Entity (MME), an Access Management Function (AMF), a Session Management Function (SMF), an SGW, a PGW, and a user plane Function UPF. In the embodiment of the present invention, only the first network unit is taken as a radio access network, and the second network unit is taken as a core network.

It is noted that in 5G mobile communication systems, the user plane CIOT may be named as another name without affecting the present invention.

In the embodiment of the present invention, suspend/release means suspend and/or release, and resuming the PDU session may also be embodied as activating the PDU session.

As shown in fig. 1, the session control method according to the embodiment of the present invention specifically includes the following steps:

step 11: and acquiring operation request information of the PDU session information.

Wherein the operation request information may include at least one of the following information: PDU session information that the terminal requests to resume, PDU session information that the terminal requests to release and PDU session information that the terminal requests to suspend.

Wherein the PDU session information may include at least one of the following information: PDU conversation identification information, recovery indication information, suspension indication information, release indication information, PDU conversation identification bit map information and QoS flow information in the PDU conversation.

Optionally, a bit position in the PDU session bitmap represents a PDU session identifier (e.g., the nth bit represents N of the PDU session identifier). The nth bit position may indicate whether an operation (such as request for resume, request for release, request for suspend, suspend success) is performed on the PDU session identified as N. For example, the nth bit is indicated as 1, which may indicate that one of the following session operations is performed on the corresponding PDU session: request activation, request recovery, request release, request suspension, acknowledge recovery, recovery success, release success, suspension success.

For example, the nth bit is indicated as 0, which may indicate that one of the following session operations is performed on the corresponding PDU session: request not activated, request not restored, request not released, request not suspended, confirmation not restored, restoration failed, release failed, suspension failed. It will be appreciated that the bytes of information that need to be transferred can be saved by the PDU session bitmap.

-when the PDU session information requesting recovery contains a PDU session bitmap, the PDU session bitmap may indicate which PDU sessions request sessions. For example, a PDU session request session indicating a PDU session identification of N may be requested by setting the nth bit to 1.

-when the release requested PDU session information contains a PDU session bitmap, the PDU session bitmap may indicate which PDU sessions request release. For example, a PDU session request release indicating a PDU session identification of N may be indicated by setting the nth bit to 1.

-when the PDU session information requesting suspension contains a PDU session bitmap, the PDU session bitmap may indicate which PDU session requests are suspended. For example, a PDU session request pending may be indicated by setting the nth bit to 1 indicating a PDU session identification of N.

-when the recovery confirmed PDU session information or the non-recovery confirmed PDU session contains a PDU session bitmap, the PDU session bitmap may indicate which PDU session acknowledgements are recovered and/or which PDU session acknowledgements are not recovered. For example, the recovery may be requested by setting the nth bit to 1 to indicate that the PDU session is identified as N. For example, a PDU session request acknowledgment that indicates a PDU session identification of N may not be recovered by setting the nth bit to 0.

-when the PDU session recovery result information contains a PDU session bitmap, the PDU session bitmap may indicate which PDU sessions recovered successfully and/or which PDU sessions acknowledged failed to recover. For example, the PDU session recovery success of the PDU session id N can be indicated by setting the nth bit to 1. For example, a PDU session recovery failure with a PDU session flag of N may be indicated by setting the nth bit to 0.

Optionally, the PDU session identification information may include QoS flow identification information the PDU session identification bitmap information may include QoS flow identification bitmap information, and the QoS flow information may include QoS flow mapped radio bearer information. In general, a PDU session may contain multiple QoS flows. Only if there is at least one QoS flow requesting restoration, the PDU session of its corresponding PDU needs to request restoration.

Step 12: and carrying out PDU session processing according to the operation request information.

In one embodiment, step 12 may include at least one of:

when the operation request information is PDU session information which the terminal requests to resume, at least one of the following may be performed: carrying out recovery operation on the PDU session which is requested to be recovered by the terminal; restoring all PDU sessions suspended by the terminal; and performing recovery operation on all PDU sessions suspended by the terminal, and preferentially performing recovery operation on the PDU session requested to be recovered by the terminal when resources are insufficient. The resources may include various resources such as wireless resources, a CPU inside the first network unit, and a memory. In one embodiment, the priority means that the PDU sessions requested to be resumed by the UE are PDU session 1 and PDU session 2, but the terminal has the pending PDU sessions PDU session 1, PDU session 2, PDU session 3, PDU session 4 and PDU session 5. The first network unit is full recovery when the resources are sufficient, but when the resources are insufficient, the PDU session 1 and the PDU session 2 are preferentially recovered, and if extra resources exist after the PDU session 1 and the PDU session 2 are recovered, the PDU session 3, the PDU session 4 and the like can be further recovered.

When the operation request information contains the PDU session information requested to be released by the terminal, a release operation may be performed on the PDU session requested to be released by the terminal.

When the operation request information contains the PDU session information requested to be suspended by the terminal, the suspension operation can be carried out on the PDU session requested to be suspended by the terminal.

It should be noted that the step of performing recovery operation on the PDU session may be: at least one of the following operations may be performed on the PDU session: restoring the context of the PDU session; recovering the radio bearer corresponding to the PDU session; allocating and/or mapping radio bearer resources for the QoS flows of the PDU session; the connection between the first network element and the second network element with respect to the terminal is restored.

Further, step 12 may also include at least one of: sending PDU session information which confirms recovery and/or confirms that recovery cannot be carried out to the terminal; and sending PDU session recovery result information of the first network unit to the second network unit. That is, while or after the first network unit processes the PDU session, the first network unit may also generate the PDU session information confirming recovery and/or confirming non-recovery according to the processing result and feed back the PDU session information to the terminal; and secondly, while or after the first network unit processes the PDU session, the first network unit can generate a PDU session recovery result of the first network unit according to the processing result and send the PDU session recovery result to the second network unit. The embodiment of the present invention does not limit the precedence relationship between the two steps (the first step and the second step), or the precedence relationship between the processing procedure and the transmission of the processing result, and may transmit the processing result while processing the processing result, or transmit the processing result after all the processing results are processed.

Wherein the PDU session recovery result information of the first network element may include at least one of the following information: recovering successful PDU session information, recovering failed PDU session information, requesting released PDU session information and requesting pending PDU session information.

Optionally, the recovery successful PDU session information may be used to indicate that both the terminal and the first network element recover the successful PDU session;

the recovery failed PDU session information may be used to indicate to the terminal or the first network element to recover the failed PDU session;

the release-requested PDU session information may be used to indicate at least one of a recovery-failed PDU session of the terminal, a recovery-failed PDU session of the first network element, and a release-requested PDU session of the terminal;

the suspension-requested PDU session information may be used to indicate at least one of a recovery-failed PDU session of the terminal, a recovery-failed PDU session of the first network element, and a request for suspension of the PDU session by the terminal;

the confirmation of the recovered PDU session information may be for indicating at least one of a PDU session in which a PDU session context exists, a PDU session in which radio bearer resources can be allocated or mapped, the first network element and the second network element both confirming the recovery-capable PDU session;

confirming the unrecoverable PDU session may include: at least one of a PDU session for which there is no PDU session context, a PDU session for which radio bearer resources cannot be allocated or mapped, a first network element acknowledging an unrecoverable PDU session, a second network element acknowledging an unrecoverable PDU session.

Optionally, after the step of sending the PDU session information that the recovery is confirmed and/or the recovery cannot be confirmed to the terminal, the method may further include: and receiving PDU recovery result information of the terminal fed back by the terminal. The PDU recovery result information of the terminal may include: and at least one of the PDU session information of which the terminal is successfully recovered and the PDU session information of which the terminal is unsuccessfully recovered.

Optionally, the step of sending the PDU session recovery result information of the first network element to the second network element may further include: sending a session operation request carrying PDU session recovery result information of the first network unit to the second network unit; and receiving PDU session recovery result information of the second network unit returned by the second network unit according to the session operation request.

Optionally, the PDU session recovery result information of the second network element may include at least one of the following information: the method comprises the steps of recovering successful PDU session information, recovering failed PDU session information, recovering requested PDU session information, releasing requested PDU session information and hanging requested PDU session information.

Specifically, the recovery successful PDU session information may be used to indicate that the first network element and the second network element both recover the successful PDU session;

the recovery failed PDU session information may be used to indicate to the second network element to recover the failed PDU session;

the PDU session information that the second network element requests to resume may be used to indicate at least one of a PDU session that the first network element is suspended but that the second network element requests to resume, a PDU session that the first network element is still suspended without a resumption failure but that the second network element requests to resume;

the PDU session information requested to be released by the second network element may be used to indicate at least one of a PDU session failed to be recovered by the second network element, a PDU session successful to be recovered by the first network element but requested to be released by the second network element;

the PDU session information that the second network element requests to suspend may be used to indicate at least one of a PDU session that the terminal failed to resume, a PDU session that the first network element succeeded in resuming, but the second network element requested to release.

Wherein, the step of receiving the PDU session recovery result information of the second network element returned by the second network element according to the session operation request may further include: and processing the PDU session of the terminal according to the PDU session recovery result information of the second network unit. An example is: the first network element recovers the PDU sessions 1 and 2 of the terminal, but the second network element recovers the PDU session 1 successfully and fails the PDU session 2. At this point, it is understood that for recovering the failed PDU session 2, the second network element may indicate that PDU session 2 failed to recover, request release of PDU session 2, or request suspension of PDU session 2.

Optionally, specific contents of the step of processing the PDU session of the terminal according to the PDU session recovery result information of the second network unit are as follows, and are not described herein again.

In another embodiment, step 12 may comprise: when the operation request information includes PDU session information that the terminal requests to resume, it may perform: and sending PDU session information which is requested to be recovered by the terminal to the second network unit.

After the step of sending the PDU session information requested to be recovered by the terminal to the second network element, the method may further include: receiving PDU conversation recovery result information of the second network unit fed back by the second network unit according to the PDU conversation information required to be recovered by the terminal; the PDU session of the terminal may be processed according to the PDU session recovery result information of the second network element.

It is worth pointing out that the PDU session recovery result information of the second network element may include at least one of the following information: the second network unit recovers the successful PDU session information, the second network unit recovers the failed PDU session information, the second network unit requests the recovery PDU session information, the second network unit requests the release PDU session information, and the second network unit requests the suspension PDU session information.

An example is: the first network element resumes PDU session 1, 2, 3 of the terminal and it is PDU session 1 that the terminal requests to resume. The second network element succeeds in recovering the terminal-requested PDU session 1. The second network unit finds the PDU session 2 with the requirement of downlink data transmission at the same time, and recovers the PDU session 2 unsuccessfully. At this point, it is understood that for the redundant resumed PDU session 3, the second network element may indicate a request to release PDU session 3 or a request to suspend PDU session 3.

Another example is: the first network element sends a terminal request to the second network element to resume PDU session 1. The second network element succeeds in recovering the terminal-requested PDU session 1. The second network unit finds the PDU session 2 with the requirement of downlink data transmission at the same time, and recovers the PDU session 2 unsuccessfully. At this point, it will be appreciated that for the redundant recovery PDU session 3, the second network element may indicate the recovery successful PDU sessions 1 and 2 and send to the first network element. The first network element then corresponds to the recovery PDU sessions 1 and 2. The first network element may also instruct the UE to resume PDU sessions 1 and 2.

The step of processing the PDU session of the terminal according to the PDU session recovery result information of the second network element may include:

if the PDU session recovery result information of the second network element is the PDU session information successfully recovered by the second network element, at least one of the following operations may be performed on the PDU session successfully recovered by the second network element:

the PDU session indicated by the PDU session information successfully recovered by the second network element has not been recovered yet, and the PDU session may be recovered (as above, the recovery operation on the PDU session is not described herein again);

when detecting that the PDU session successfully recovered by the second network element cannot be recovered at the first network element or the terminal side, sending request information requesting to release or suspend the PDU session to the second network element;

if the PDU session recovery result information of the second network element is the PDU session information of the second network element that failed to recover, at least one of the following operations may be performed on the PDU session of the second network element that failed to recover:

suspending recovery of the failed PDU session context by the second network element,

Suspending the second network element to recover the context of the radio bearer corresponding to the failed PDU session,

Releasing the bearing resource corresponding to the PDU conversation which is failed to recover by the second network unit,

Storing the uplink transport address of the PDU session for which the recovery of the second network element failed,

Setting the PDU session state of the second network unit which fails to recover as suspended,

Requesting the terminal to suspend the second network element from recovering the failed PDU session,

Requesting the terminal to delete the PDU session context that failed to recover the second network element,

Requesting the terminal to delete the PDU session which fails to be recovered by the second network unit;

if the PDU session recovery result information of the second network element is the PDU session information requested to be recovered by the second network element, at least one of the following operations may be performed on the PDU session requested to be recovered by the second network element:

restoring the context of the PDU session the second network element requests to restore,

Restoring the radio bearer corresponding to the PDU session requested to be restored by the second network element,

Allocation or mapping of radio bearer resources for the PDU session the second network element requests for recovery,

Restoring the connection with the second network element with respect to the terminal;

if the PDU session recovery result information of the second network element is the PDU session information requested to be released by the second network element, at least one of the following operations may be performed on the PDU session requested to be released by the second network element:

releasing the context of the PDU session requested to be released by the second network element,

Releasing the radio bearer context corresponding to the PDU session requested to be released by the second network element,

The radio bearer resource corresponding to the PDU session requested to be released by the second network unit is released,

Sending PDU session information requested to be released by the second network unit to the terminal;

if the PDU session resumption result information of the second network element is the PDU session information requested to be suspended by the second network element, at least one of the following operations may be performed on the PDU session requested to be suspended by the second network element:

suspending the context of the PDU session the second network element requests to suspend,

Suspending radio bearer context corresponding to the PDU session the second network element requests to suspend,

Releasing the radio bearer resource corresponding to the PDU session requested to be suspended by the second network element,

And sending the PDU session information which is requested to be suspended by the second network unit to the terminal.

In another embodiment, step 12 may include at least one of:

when the operation request information includes PDU session information that the second network element requests to resume, at least one of the following may be performed: sending the acquired PDU session information which is requested to be recovered by the second network unit to the terminal;

the first network element may comprise at least one of: a radio access network device, a radio access network node, a radio access network functional unit, a central unit CU, a distributed unit DU, a base station, an eNB, a gNB, an N3IWF, an access control node AC, an access point AP device, or a wireless local area network WLAN node.

The second network element may comprise at least one of: the system comprises core network equipment, core network nodes, a core network functional unit, an MME, an AMF, an SMF, an SGW, a PGW and a user plane function UPF.

The specific operation flow of the first network element in the session control method is introduced above, and the following embodiment will further describe the operation flow with reference to specific scenarios.

Scene one,

The first network unit processes the PDU session according to the PDU session information which the terminal requests to recover, release and/or suspend.

Examples one,

The first network unit obtains the operation request information of the PDU session information and carries out PDU session processing according to the operation request information. Wherein, the operation request information may include: the terminal requests the PDU session information to resume, release and/or suspend.

Specifically, the first network element may obtain PDU session information that the terminal requests to resume, release, and/or suspend by receiving a Radio Resource Control (RRC) resume request (i.e., operation request information) sent by the terminal.

When the RRC recovery request carries PDU session information that the terminal requests to recover, the first network element may perform a recovery operation on the PDU session that the terminal requests to recover.

When the RRC recovery request carries the PDU session information requested to be released by the terminal, a release operation may be performed on the PDU session requested to be released by the terminal.

When the RRC resume request carries the PDU session information that the terminal requests to suspend, the suspension operation may be performed on the PDU session that the terminal requests to suspend.

During the process of recovering, releasing and suspending the PDU session requested to be recovered by the terminal, the first network unit can also generate at least one of PDU session information confirming recovery and/or PDU session information confirming non-recovery and PDU session recovery result information of the first network unit according to the processing result. The first network element may send the PDU session information indicating recovery and/or failure to recover to the terminal, and may receive the PDU recovery result information of the terminal fed back by the terminal after sending the PDU session information indicating recovery and/or failure to recover to the terminal. Further, the first network element may also send PDU session recovery result information of the first network element to the second network element, specifically send a session operation request carrying the PDU session recovery result information of the first network element to the second network element; after the session operation request is sent, the PDU session recovery result information of the second network unit, which is returned by the second network unit according to the session operation request, may also be received, and then the PDU session of the terminal may be processed according to the PDU session recovery result information of the second network unit. It is noted that the embodiment of the present invention does not limit the sequence relationship between the two steps.

Further, the PDU session recovery result information of the second network element may comprise at least one of the following information: the second network unit recovers the successful PDU session information, the second network unit recovers the failed PDU session information, the second network unit requests the recovery PDU session information, the second network unit requests the release PDU session information, and the second network unit requests the suspension PDU session information. The step of the first network element processing the PDU session of the terminal according to the PDU session recovery result information of the second network element may be implemented with reference to the following manner:

if the PDU session recovery result information of the second network element is the PDU session information successfully recovered by the second network element, when detecting that the PDU session successfully recovered by the second network element cannot be recovered at the first network element or the terminal side, sending a request information requesting to release or suspend the PDU session to the second network element;

Examples two,

Different from the example one, when the RRC resume request carries PDU session information that the terminal requests to resume, the first network element may perform a resume operation on all PDU sessions suspended by the terminal.

Examples III,

Different from the second example, the second example considers system resources, and specifically, when the RRC resume request carries PDU session information that the terminal requests to resume, the first network element may perform a resume operation on all PDU sessions suspended by the terminal, and preferentially perform the resume operation on the PDU session that the terminal requests to resume when resources are insufficient.

Scene two,

Different from the first scenario, after receiving the operation request information sent by the terminal, the first network unit may directly forward the operation request information to the second network unit, and receive PDU session recovery result information of the second network unit, which is fed back by the second network unit according to the PDU session information requested to be recovered by the terminal; the PDU session of the terminal may be processed according to the PDU session recovery result information of the second network element.

In the session control method of the embodiment of the invention, a first network unit acquires operation request information of PDU session information of a packet data unit; according to the operation request information, PDU session processing can be carried out. Wherein the operation request information may include at least one of the following information: PDU session information that the terminal requests to restore, PDU session information that the terminal requests to release and PDU session information that the terminal requests to suspend. Therefore, through the mutual cooperation among the terminal, the first network unit and the second network unit, when the connection of the suspended terminal is recovered, the recovery of the PDU session can be carried out according to the PDU session information needing to be recovered in the operation request information, thereby saving the resources of the wireless access network and reducing the signaling overhead.

The above embodiments respectively describe in detail the session control methods in different scenarios, and the following embodiments further describe the corresponding network devices with reference to the accompanying drawings.

As shown in fig. 2, the network device 200 according to the embodiment of the present invention can implement the operation request information for obtaining the PDU session information in the foregoing embodiment, and perform the details of the PDU session processing method according to the operation request information, and achieve the same effect, the network device 200 may include the following functional modules:

a first obtaining module 210, configured to obtain operation request information of packet data unit PDU session information; the operation request information may include at least one of the following information: PDU session information which is requested to be recovered by a terminal, PDU session information which is requested to be released by the terminal and PDU session information which is requested to be hung by the terminal;

the first processing module 220 may be configured to perform PDU session processing according to the operation request information.

The first processing module 220 may include:

the first processing sub-module may be configured to, when the operation request information is PDU session information that the terminal requests to resume, perform at least one of the following: carrying out recovery operation on the PDU session which is requested to be recovered by the terminal; restoring all PDU sessions suspended by the terminal; restoring all PDU sessions suspended by the terminal, and preferentially restoring the PDU session requested to be restored by the terminal when resources are insufficient;

the second processing submodule can be used for performing release operation on the PDU session requested to be released by the terminal when the operation request information is the PDU session information requested to be released by the terminal;

and the third processing sub-module may be configured to perform a suspend operation on the PDU session requested to be suspended by the terminal when the operation request information is the PDU session information requested to be suspended by the terminal.

The recovering operation of the PDU session may be:

performing at least one of the following operations on the PDU session:

restoring the context of the PDU session;

recovering the radio bearer corresponding to the PDU session;

allocating and/or mapping radio bearer resources for the QoS flows of the PDU session;

the connection between the first network element and the second network element with respect to the terminal is restored.

Wherein the first processing module may further comprise at least one of:

the first sending submodule can be used for sending the PDU session information which confirms recovery and/or cannot be recovered to the terminal;

and the number of the first and second groups,

the second sending submodule may be configured to send PDU session recovery result information of the first network element to the second network element; wherein the PDU session recovery result information of the first network element may include at least one of the following information: recovering successful PDU session information, recovering failed PDU session information, requesting released PDU session information and requesting pending PDU session information.

The PDU session information that is successfully recovered may be used to indicate that both the terminal and the first network element successfully recover the PDU session;

Wherein, the first processing module may further include:

the first receiving submodule can be used for receiving PDU recovery result information of the terminal fed back by the terminal; the PDU recovery result information of the terminal may include: and at least one of the PDU session information of which the terminal is successfully recovered and the PDU session information of which the terminal is unsuccessfully recovered.

Wherein, the second sending submodule may include:

a first sending unit, configured to send a session operation request carrying PDU session recovery result information of the first network element to the second network element;

the first receiving unit may be configured to receive PDU session recovery result information of the second network unit, where the PDU session recovery result information is returned by the second network unit according to the session operation request.

Wherein, the first processing module may further include:

and the processing submodule can be used for processing the PDU session of the terminal according to the PDU session recovery result information of the second network unit.

Wherein, the first processing module may include:

a fourth processing sub-module, configured to, when the operation request information includes PDU session information that the terminal requests to resume, perform: and sending PDU session information which is requested to be recovered by the terminal to the second network unit.

Wherein, the first processing module may further include:

the second receiving submodule can be used for receiving PDU session recovery result information of the second network unit, which is fed back by the second network unit according to the PDU session information requested to be recovered by the terminal;

Wherein the PDU session recovery result information of the second network element may include at least one of the following information: the second network unit recovers the successful PDU session information, the second network unit recovers the failed PDU session information, the second network unit requests the recovery PDU session information, the second network unit requests the release PDU session information and the second network unit requests the suspension PDU session information.

Wherein, the processing submodule may include:

the first processing unit may be configured to send, to the second network unit, request information requesting release or suspension of the PDU session when it is detected that the PDU session of the second network unit that is successfully recovered cannot be recovered at the first network unit or the terminal side if the PDU session recovery result information of the second network unit is PDU session information of the second network unit that is successfully recovered;

the second processing unit may be configured to, if the PDU session recovery result information of the second network element is PDU session information that the second network element fails to recover, perform at least one of the following operations on the PDU session that the second network element fails to recover:

the third processing unit may be configured to, if the PDU session recovery result information of the second network element is the PDU session information requested to be recovered by the second network element, perform at least one of the following operations on the PDU session requested to be recovered by the second network element:

the fourth processing unit may be configured to, if the PDU session recovery result information of the second network unit is the PDU session information requested to be released by the second network unit, perform at least one of the following operations on the PDU session requested to be released by the second network unit:

the fifth processing unit may be configured to, if the PDU session recovery result information of the second network unit is the PDU session information requested to be suspended by the second network unit, perform at least one of the following operations on the PDU session requested to be suspended by the second network unit:

Wherein the first network element may comprise at least one of: the system comprises wireless access network equipment, wireless access network nodes, a wireless access network function unit, a centralized unit CU, a distributed unit DU, a base station, a non-3GPP interoperation function N3IWF, an access control node AC, access point AP equipment or a wireless local area network WLAN node;

the second network element may comprise at least one of: the system comprises core network equipment, core network nodes, a core network function unit, a mobile management entity MME, an access management function AMF, a session management function SMF, an SGW, a PGW and a user plane function UPF.

It is worth pointing out that, the network device according to the embodiment of the present invention obtains the operation request information of the packet data unit PDU session information; and carrying out PDU session processing according to the operation request information. Wherein the operation request information may include at least one of the following information: PDU session information that the terminal requests to restore, PDU session information that the terminal requests to release and PDU session information that the terminal requests to suspend. Therefore, through the mutual cooperation among the terminal, the first network unit and the second network unit, when the connection of the suspended terminal is recovered, the recovery of the PDU session can be carried out according to the PDU session information needing to be recovered in the operation request information, thereby saving the resources of the wireless access network and reducing the signaling overhead.

In another embodiment, the session control method is applied to the first network element, as shown in fig. 3, and further includes the following steps:

step 31: and acquiring operation request information of the PDU session information.

Wherein the operation request information may include at least one of the following information: the second network unit requests the recovered PDU session information, the second network unit requests the release of the PDU session information, and the second network unit requests the suspended PDU session information.

Alternatively, a bit position in the PDU session bitmap may represent the PDU session identifier (e.g., the nth bit represents the PDU session identifier of N). The nth bit position may indicate whether an operation (such as request for resume, request for release, request for suspend, suspend success) is performed on the PDU session identified as N. For example, the nth bit is indicated as 1, which may indicate that one of the following session operations is performed on the corresponding PDU session: request activation, request recovery, request release, request suspension, acknowledge recovery, recovery success, release success, suspension success.

Optionally, the PDU session information may include at least one of the following information: QoS flow identification information, recovery indication information, suspension indication information, release indication information, QoS flow identification bitmap information, and QoS flow mapped radio bearer information. In general, a PDU session may contain multiple QoS flows. Only if there is at least one QoS flow requesting restoration, the PDU session of its corresponding PDU needs to request restoration.

Step 32: and carrying out PDU session processing according to the operation request information.

In one embodiment, step 32 may include at least one of:

when the operation request information contains the PDU session information which is requested to be recovered by the second network unit, the recovery operation can be carried out on the PDU session which is requested to be recovered by the second network unit;

when the operation request information contains the PDU session information requested to be released by the second network unit, the PDU session requested to be released by the second network unit can be released;

when the operation request message contains the PDU session information requested to be suspended by the second network element, the suspension operation may be performed on the PDU session requested to be suspended by the second network element.

Optionally, step 32 may further include: and transmitting the operation request information to the terminal. In one embodiment, when the operation request information includes PDU session information that the second network element requests to resume, at least one of the following may be performed: sending PDU session information which is requested to be recovered by the second network unit to the terminal; when the operation request information includes PDU session information that the second network element requests to release, at least one of the following may be performed: sending a second network unit request to release PDU session information to the terminal; when the operation request information includes PDU session information that the second network element requests to suspend, at least one of the following may be performed: and sending the PDU session information which is requested to be suspended by the second network unit to the terminal.

Alternatively, step 31 may be: a paging message or a notification message sent by the second network element is received. The operation request information is carried in a paging message or a notification message. The sending of the operation request information to the terminal may be: sending the received paging message or notification message to the terminal;

the paging message or the notification message may carry at least one of information indicating that the second network unit requests the PDU session to be resumed, information indicating that the second network unit requests the PDU session to be released, and information indicating that the second network unit requests the PDU session to be suspended.

Scene three,

Unlike scenario one and scenario two, the first network element may perform PDU session processing according to the PDU session information that the second network element requests to resume, release and/or suspend.

Specifically, the first network element may receive a paging message or a notification message (i.e., operation request information) transmitted by the second network element, and transmit the received paging message or notification message to the terminal. The paging message or the notification message may carry at least one of PDU session information indicating that the second network element requests to resume, PDU session information requesting to release the second network element, and PDU session information requesting to suspend by the second network element.

When the paging message or the notification message comprises PDU session information that the second network element requests to resume, at least one of the following may be performed: sending PDU session information which is requested to be recovered by the second network unit to the terminal;

when the paging message or the notification message comprises PDU session information requested to be released by the second network element, at least one of the following may be performed: sending a second network element request to release PDU session information to the terminal

When the paging message or the notification message comprises PDU session information that the second network element requests to suspend, at least one of the following may be performed: and sending the PDU session information which is requested to be suspended by the second network unit to the terminal.

It should be noted that, in the first scenario and the second scenario, the step of performing the recovery operation on the PDU session is to perform at least one of the following operations on the PDU session: restoring the context of the PDU session; recovering the radio bearer corresponding to the PDU session; allocating and/or mapping radio bearer resources for the QoS flows of the PDU session; the connection between the first network element and the second network element with respect to the terminal is restored.

The step of suspending the PDU session is to perform at least one of the following operations on the PDU session: suspending the context of the PDU session, suspending the radio bearer context corresponding to the PDU session, releasing the radio bearer resource corresponding to the PDU session, and sending the PDU session information to the terminal.

The step of performing a release operation on the PDU session may be performing at least one of the following operations on the PDU session: and releasing the context of the PDU session, releasing the radio bearer context corresponding to the PDU session, releasing the radio bearer resource corresponding to the PDU session, and sending the PDU session information to the terminal.

In the session control method of the embodiment of the invention, a first network unit can obtain operation request information of Packet Data Unit (PDU) session information; according to the operation request information, PDU session processing can be carried out. Wherein the operation request information may include at least one of the following information: the second network unit requests the recovered PDU session information, the second network unit requests the release of the PDU session information, and the second network unit requests the suspended PDU session information. Therefore, through the mutual cooperation among the terminal, the first network unit and the second network unit, when the connection of the suspended terminal is recovered, the recovery of the PDU session can be carried out according to the PDU session information needing to be recovered in the operation request information, thereby saving the resources of the wireless access network and reducing the signaling overhead.

As shown in fig. 4, the network device 400 according to the embodiment of the present invention can implement the operation request information for obtaining the PDU session information in the foregoing embodiment, and perform the details of the PDU session processing method according to the operation request information, and achieve the same effect, the network device 400 may include the following functional modules:

a second obtaining module 410, configured to obtain operation request information of packet data unit PDU session information; the operation request information may include at least one of the following information: the second network unit requests the recovered PDU session information, the second network unit requests the release of the PDU session information and the second network unit requests the suspended PDU session information;

the second processing module 420 is configured to perform PDU session processing according to the operation request information.

Wherein the second processing module 420 may comprise at least one of:

the fifth processing sub-module may be configured to, when the operation request information is PDU session information that the second network unit requests to resume, perform a resume operation on the PDU session that the second network unit requests to resume;

the sixth processing sub-module may be configured to, when the operation request information is PDU session information requested to be released by the second network element, perform a release operation on the PDU session requested to be released by the second network element;

and the seventh processing sub-module may be configured to perform a suspend operation on the PDU session requested to be suspended by the second network element when the operation request information is the PDU session information requested to be suspended by the second network element.

Wherein, the second processing module 420 may further include:

and the third sending submodule is used for sending the operation request information to the terminal.

Optionally, the second obtaining module 410 may further perform: receiving a paging message or a notification message sent by a second network unit;

the third transmitting sub-module may further perform: sending the received paging message or notification message to the terminal;

In the network equipment of the embodiment of the invention, a first network unit acquires operation request information of PDU session information; according to the operation request information, PDU session processing can be carried out. Wherein the operation request information may include at least one of the following information: the second network unit requests the recovered PDU session information, the second network unit requests the release of the PDU session information, and the second network unit requests the suspended PDU session information. Therefore, through the mutual cooperation among the terminal, the first network unit and the second network unit, when the connection of the suspended terminal is recovered, the recovery of the PDU session can be carried out according to the PDU session information needing to be recovered in the operation request information, thereby saving the resources of the wireless access network and reducing the signaling overhead.

The above embodiment describes the session control method of the present invention from the first network element side, and the following embodiment further describes the session control method of the second network element side with reference to the drawings.

The embodiment of the invention provides a session control method, which is applied to a second network unit side, wherein a first network unit can comprise at least one of the following: the system comprises wireless access network equipment, a wireless access network node, a wireless access network function unit, a centralized unit CU, a distributed unit DU, a base station, an eNB, a gNB, a non-3GPP interoperation function N3IWF, an access control AC node, access point AP equipment or a wireless local area network WLAN node; the second network element may comprise at least one of: the system comprises core network equipment, core network nodes, a core network function unit, a mobile management entity MME, an access management function AMF, a session management function SMF, a serving gateway SGW, a PDN gateway PGW and a user plane function UPF. The third network element comprises at least one of: the system comprises core network equipment, core network nodes, a core network function unit, a mobile management entity MME, an access management function AMF, a session management function SMF, a serving gateway SGW, a PDN gateway PGW and a user plane function UPF. In the embodiment of the present invention, only the first network element is taken as the radio access network, and the second network element is taken as the AMF and the SMF in the core network for example. Such as: when the second network element is an MME, the third network element may be an SGW. When the second network element is an AMF, the third network element may be an SMF. When the second network element is an SGW, the third network element may be a PGW. When the second network element is an SMF, the third network element may be a UPF.

As shown in fig. 5, the session control method according to the embodiment of the present invention may include the following steps:

step 51: and acquiring operation request information of the PDU session information.

Wherein the operation request information may include at least one of the following information: PDU session information requested to be recovered by the terminal, PDU session information requested to be released by the terminal, PDU session information requested to be suspended by the terminal, PDU session recovery result information of the first network unit, PDU session information requested to be recovered by the third network unit, PDU session information requested to be released by the third network unit, PDU session information requested to be suspended by the third network unit, PDU session information required by downlink data transmission and PDU session information notified by the received downlink data.

Optionally, the PDU session recovery result information of the first network element may include: recovering at least one of successful PDU session information, failed PDU session information, PDU session information requested to be released and PDU session information requested to be suspended;

the PDU session information that the terminal requests to recover may be the PDU session information that the terminal requests to recover and is forwarded by the first network element or sent by the terminal; for example, after receiving the PDU session information requesting recovery sent by the terminal through the RRC message, the first network element sends the PDU session information to the second network element through an interface message such as S1/NG. Or for example, the terminal directly requests the recovered PDU session information through the NAS message.

The PDU session information requested to be released by the terminal may be the PDU session information requested to be released by the terminal and forwarded by the first network element or sent by the terminal;

the terminal request pending PDU session information may be PDU session information forwarded by the first network element or terminal request resuming sent by the terminal.

Step 52: and carrying out PDU session processing according to the operation request information.

In one embodiment, step 52 may include at least one of:

for a PDU session requiring recovery operation, at least one of the following operations can be performed:

restoring the context of the corresponding PDU session,

Sending the downlink transmission address of the corresponding PDU session to the user plane functional entity, and activating the corresponding PDU session to the user plane functional entity;

the PDU session that needs to be recovered may include: the PDU session recovery result information of the first network unit indicates a successful recovery PDU session, the PDU session indicated by the PDU session information requested to be recovered by the terminal, the PDU session indicated by the PDU session information requested to be recovered by the third network unit, the PDU session indicated by the PDU session information required to be transmitted by downlink data, the PDU session indicated by the PDU session information notified by downlink data, the PDU session recovery result information of the first network unit indicates a successful recovery and the PDU session requested to be recovered by the third network unit, the PDU session indicated by the PDU session information required to be transmitted by downlink data and the PDU session recovery result information of the first network unit indicates a successful recovery and the PDU session indicated by the PDU session information notified by downlink data, and the terminal requests to recover and the PDU session recovery result information of the first network unit indicates at least one item of the PDU sessions which are successfully recovered.

At least one of the PDU session indicated by the PDU session information requested to be released by the terminal and the PDU session indicated by the PDU session information requested to be released by the first network element may perform the following operations: releasing the PDU session which the terminal and/or the second network element requested to be released.

At least one of the PDU session indicated by the terminal request pending PDU session information and the PDU session indicated by the first network element request pending PDU session information may perform the following operations: the terminal and/or the second network element requesting the released PDU session is suspended.

For the recovery-failed PDU session indicated by the PDU session recovery result information of the first network element, at least one of the following operations may be performed:

suspending the context of a recovery failed PDU session,

Deleting the context of the PDU session with failed recovery,

And requesting the user plane function to delete the PDU session with failed recovery.

Optionally, after step 52, the method may further include:

and generating PDU session recovery result information of the second network unit, and sending the PDU session recovery result information of the second network unit to the first network unit and/or sending the PDU session recovery result information of the second network unit to the terminal through the first network unit. Wherein the PDU session recovery result information of the second network element may include at least one of the following information: the second network unit recovers the successful PDU session information, the second network unit recovers the failed PDU session information, the second network unit requests the recovered PDU session information, the second network unit requests the released PDU session information, and the second network unit requests the suspended PDU session information;

specifically, the PDU session information that the second network requests to recover may include: at least one item of PDU session information required by downlink data transmission, PDU session receiving downlink data notification and PDU session requested to be recovered by the third network unit;

the PDU session information that the second network requests to suspend may include: at least one of the PDU session which fails to be recovered by the second network, the PDU session which succeeds to be recovered by the first network unit but fails to be recovered by the second network, and the PDU session which succeeds to be recovered by the first network unit and the terminal but fails to be recovered by the second network;

the PDU session information requested to be released by the second network may include: at least one of the second network recovering the failed PDU session, the first network recovering the successful PDU session but the second network recovering the failed PDU session.

In one embodiment, step 52 may comprise: when the operation request information is at least one of the PDU session information requested to be recovered by the third network unit, the PDU session information requested to be released by the third network unit, the PDU session information requested to be suspended by the third network unit, and the PDU session information notified by the received downlink data, at least one of the PDU session information requested to be recovered by the third network unit, the PDU session information requested to be suspended by the third network unit, and the PDU session information notified by the received downlink data may be sent to the first network unit through a paging request or a notification message.

The specific operation flow of the second network element in the session control method is introduced above, and the following embodiment will further describe the operation flow with reference to specific scenarios.

Scene four,

Corresponding to the scenario one, the first network unit obtains PDU session information requested to be resumed, released and/or suspended by the terminal by receiving a Radio Resource Control (RRC) resume request (i.e., operation request information) sent by the terminal, and performs resume, release and/or suspension processing on a corresponding PDU session. During the process of recovering, releasing and suspending the PDU session requested to be recovered by the terminal, the first network element may also recover result information of the PDU session of the first network element according to the processing result, and send the result information to the second network element (e.g., AMF). The PDU session recovery result information of the first network element may comprise at least one of the following information: the terminal requests the recovery, release and/or suspension of the PDU session information, the recovery of the successful PDU session information, the recovery of the failed PDU session information, the release of the requested PDU session information and the suspension of the requested PDU session information. In addition, the second network element may also obtain PDU session information that the third network element (e.g., SMF, user plane function, etc.) requests to resume, release, and/or suspend, and PDU session information that there is a downlink data transmission requirement and/or PDU session information that a downlink data notification is received.

After obtaining the PDU session information that needs to be processed, the second network element (e.g., SMF) may perform the following operations:

for the PDU session requiring recovery operation, for example, the PDU session indicated by the PDU session recovery result information of the first network unit indicating recovery success, the PDU session indicated by the PDU session information requested to be recovered by the terminal, the PDU session indicated by the PDU session information requested to be recovered by the third network unit, the PDU session indicated by the PDU session information required to be transmitted by the downlink data, the PDU session indicated by the PDU session information notified by the downlink data, the PDU session recovery result information of the first network unit indicating recovery success and the PDU session requested to be recovered by the third network unit, the PDU session indicated by the PDU session recovery result information of the first network unit indicating recovery success and the PDU session indicated by the PDU session information requested to be recovered by the terminal and the PDU session recovery result information indicated by the PDU session information requested to be recovered by the first network unit indicating recovery success May perform at least one of the following operations:

restoring the context of the corresponding PDU session,

at least one of the PDU session indicated by the PDU session information requested to be released by the terminal and the PDU session indicated by the PDU session information requested to be released by the first network element may perform the following operations: releasing the PDU session requested to be released by the terminal and/or the second network unit;

at least one of the PDU session indicated by the terminal request pending PDU session information and the PDU session indicated by the first network element request pending PDU session information may perform the following operations: suspending the PDU session requested to be released by the terminal and/or the second network unit;

suspending the context of a recovery failed PDU session,

Deleting the context of the PDU session with failed recovery,

And requesting the user plane functional entity to delete the PDU session with failed recovery.

Optionally, after the second network element performs the above operation on the corresponding PDU session, the method may further include: and generating PDU session recovery result information of the second network unit, and sending the PDU session recovery result information of the second network unit to the first network unit and/or sending the PDU session recovery result information of the second network unit to the terminal through the first network unit. Thus, the first network unit can further process the PDU session according to the PDU session recovery result information of the second network unit, and the processing manner of the PDU session recovery result information can refer to the first scenario, which is not described herein again.

Scene five,

Corresponding to scenario two, the first network element may directly forward the operation request information to the second network element after receiving the operation request information sent by the terminal, and the second network element directly processes the PDU session of the terminal according to the operation request. Wherein, the operation request information may include: the terminal requests the PDU session information to resume, release and/or suspend. Besides processing the PDU session, the second network unit may also obtain, as in scenario four, PDU session information that the third network unit (such as SMF, user plane function, etc.) requests to resume, release, and/or suspend, and PDU session information that has a downlink data transmission requirement and/or PDU session information that receives a downlink data notification. The second network unit may refer to scenario four for processing the corresponding PDU session, and therefore, details are not described herein.

A sixth scene,

Corresponding to the third scenario, the second network unit obtains PDU session information that the third network unit (such as SMF, user plane function, etc.) requests to recover, release and/or suspend, and PDU session information that has a downlink data transmission requirement and/or PDU session information that receives a downlink data notification; and can send the PDU conversation information that the third network unit requests to resume, release and/or suspend, and PDU conversation information that has downlink data transmission demand and/or PDU conversation information that receives downlink data notice to the first network unit through paging request or notice message.

In the session control method of the embodiment of the invention, the second network unit obtains the operation request information of the PDU session information of the packet data unit; and carrying out PDU session processing according to the operation request information. Wherein the operation request information may include at least one of the following information: the operation request information includes at least one of the following information: the terminal requests the PDU session information of the recovery, the terminal requests the PDU session information of the release, the terminal requests the PDU session information of the suspension, the PDU session recovery result information of the first network unit, the third network unit requests the PDU session information of the recovery, the third network unit requests the PDU session information of the release, the third network unit requests the PDU session information of the suspension, the PDU session information with the requirement of the downlink data transmission and/or the PDU session information which receives the downlink data notification. Therefore, through the mutual cooperation among the terminal, the first network unit and the second network unit, when the connection of the suspended terminal is recovered, the recovery of the PDU session can be carried out according to the PDU session information needing to be recovered in the operation request information, thereby saving the resources of the wireless access network and reducing the signaling overhead.

As shown in fig. 6, a network device 600 according to an embodiment of the present invention can implement the operation request information for obtaining the PDU session information in the foregoing embodiment, and perform details of a PDU session processing method according to the operation request information, and achieve the same effect, where the network device 600 specifically includes the following functional modules:

a third obtaining module 610, configured to obtain operation request information of packet data unit PDU session information; the operation request information may include at least one of the following information: PDU session information requested to be recovered by the terminal, PDU session information requested to be released by the terminal, PDU session information requested to be suspended by the terminal, PDU session recovery result information of the first network unit, PDU session information requested to be recovered by the third network unit, PDU session information requested to be released by the third network unit, PDU session information requested to be suspended by the third network unit, PDU session information required by downlink data transmission and PDU session information notified by the received downlink data;

the third processing module 620 may be configured to perform PDU session processing according to the operation request information.

Wherein the PDU session recovery result information of the first network element may include at least one of the following information: recovering successful PDU session information, recovering failed PDU session information, requesting released PDU session information and requesting suspended PDU session information;

the PDU session information that the terminal requests to recover may be the PDU session information that the terminal requests to recover and is forwarded by the first network element or sent by the terminal;

Wherein the third processing module 620 may include at least one of:

the eighth processing sub-module, configured to perform, on a PDU session that needs to be recovered, at least one of the following operations:

restoring the context of the corresponding PDU session,

the PDU session that needs to be recovered may include: the PDU session recovery result information of the first network unit indicates the recovery successful PDU session, the PDU session indicated by the PDU session information requested to be recovered by the terminal, the PDU session indicated by the PDU session information requested to be recovered by the third network unit, the PDU session indicated by the PDU session information required by downlink data transmission, the PDU session indicated by the PDU session information notified by the downlink data, the PDU session recovery result information of the first network unit indicates at least one of the PDU session which is successfully recovered and the recovery of which is requested by the third network unit, the PDU session which is successfully recovered and indicated by the PDU session information which is required by downlink data transmission and indicated by the PDU session recovery result information of the first network unit, the PDU session which is successfully recovered and indicated by the PDU session information which is notified by the downlink data and indicated by the PDU session information which is successfully recovered and received by the PDU session recovery result information of the first network unit, and the PDU session which is successfully recovered and indicated by the PDU session recovery result information of which is requested by the terminal and recovered by the PDU session recovery result information of the first network unit.

A ninth processing sub-module, configured to perform the following operations on at least one of the PDU session indicated by the PDU session information requested to be released by the terminal and the PDU session indicated by the PDU session information requested to be released by the first network element: releasing the PDU session requested to be released by the terminal and/or the second network unit;

a tenth processing sub-module, configured to perform the following operations on at least one of the PDU session indicated by the PDU session information requested to be suspended by the terminal and the PDU session indicated by the PDU session information requested to be suspended by the first network element: suspending the PDU session requested to be released by the terminal and/or the second network unit;

an eleventh processing sub-module, configured to perform, on the PDU session indicated by the PDU session recovery result information of the first network element, at least one of the following operations:

suspending the context of a recovery failed PDU session,

Deleting the context of the PDU session with failed recovery,

The network device 600 may further include:

a first generating module, configured to generate PDU session recovery result information of a second network element; wherein the PDU session recovery result information of the second network element may include at least one of the following information: the second network unit recovers the successful PDU session information, the second network unit recovers the failed PDU session information, the second network unit requests the recovered PDU session information, the second network unit requests the released PDU session information, and the second network unit requests the suspended PDU session information;

the second sending module may be configured to send the PDU session recovery result information of the second network element to the first network element and/or to the terminal through the first network element.

Wherein the PDU session information that the second network requests to resume may include at least one of: PDU conversation information required by downlink data transmission, PDU conversation receiving downlink data notification, and PDU conversation requested to be recovered by the third network unit;

the second network requested pending PDU session information may comprise at least one of: the second network recovers the failed PDU session, the first network unit recovers the successful PDU session but the second network recovers the failed PDU session, the first network unit and the terminal recovers the successful PDU session but the second network recovers the failed PDU session;

the PDU session information requested to be released by the second network may contain at least one of: the second network recovers the failed PDU session, the first network unit recovers the successful PDU session but the second network recovers the failed PDU session, the first network unit and the terminal recovers the successful PDU session but the second network recovers the failed PDU session.

The third processing module 620 may further include:

and the twelfth processing sub-module may be configured to send, to the first network unit, at least one of the PDU session information requested to be restored by the third network unit, the PDU session information requested to be suspended by the third network unit, and the PDU session information notified by the downlink data, through a paging request or a notification message, at least one of the PDU session information requested to be restored by the third network unit, the PDU session information requested to be suspended by the third network unit, and the PDU session information notified by the downlink data.

Wherein the first network element may comprise at least one of: the wireless access network equipment, the wireless access network node, the wireless access network functional unit, the centralized unit CU, the distributed unit DU, the base station, the eNB, the gNB, the N3IWF, the AC, the access point AP equipment or the wireless local area network WLAN node;

the second network element may comprise at least one of: the system comprises core network equipment, core network nodes, a core network function unit, a mobile management entity MME, an access management function AMF, a session management function SMF, a service gateway SGW, a PDN gateway PGW and a user plane function UPF;

the third network element may comprise at least one of: the system comprises core network equipment, core network nodes, a core network function unit, a mobile management entity MME, an access management function AMF, a session management function SMF, a serving gateway SGW, a PDN gateway PGW and a user plane function UPF.

The network equipment of the embodiment of the invention obtains the operation request information of the PDU session information of the grouped data unit; and carrying out PDU session processing according to the operation request information. Wherein the operation request information may include at least one of the following information: the operation request information may include at least one of the following information: PDU session information requested to be recovered by the terminal, PDU session information requested to be released by the terminal, PDU session information requested to be suspended by the terminal, PDU session recovery result information of the first network unit, PDU session information requested to be recovered by the third network unit, PDU session information requested to be released by the third network unit, PDU session information requested to be suspended by the third network unit, PDU session information required by downlink data transmission and PDU session information notified by the received downlink data. Therefore, through the mutual cooperation among the terminal, the first network unit and the second network unit, when the connection of the suspended terminal is recovered, the recovery of the PDU session can be carried out according to the PDU session information needing to be recovered in the operation request information, thereby saving the resources of the wireless access network and reducing the signaling overhead.

In order to better achieve the above object, an embodiment of the present invention further provides a network device, which includes a processor, a memory, and a computer program stored in the memory and running on the processor, and the processor implements the steps in the session control method as above when executing the computer program. Embodiments of the present invention also provide a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the steps of the above session control method.

Specifically, the embodiment of the invention also provides a network device. As shown in fig. 7, the network device 700 may include: an antenna 71, a radio frequency device 72, a baseband device 73. The antenna 71 is connected to a radio frequency device 72. In the uplink direction, the rf device 72 receives information via the antenna 71 and sends the received information to the baseband device 73 for processing. In the downlink direction, the baseband device 73 processes information to be transmitted and transmits the information to the rf device 72, and the rf device 72 processes the received information and transmits the processed information through the antenna 71.

The above-mentioned band processing means may be located in the baseband means 73, and the method performed by the network device in the above embodiment may be implemented in the baseband means 73, where the baseband means 73 includes a processor 74 and a memory 75.

The baseband device 73 may include, for example, at least one baseband board, on which a plurality of chips are disposed, as shown in fig. 7, wherein one of the chips, for example, the processor 74, is connected to the memory 75 to call up the program in the memory 75 to perform the network device operation shown in the above method embodiment.

The baseband device 73 may further include a network interface 76, such as a Common Public Radio Interface (CPRI), for exchanging information with the radio frequency device 72.

The processor may be a single processor or a combination of multiple processing elements, for example, the processor may be a CPU, an ASIC, or one or more integrated circuits configured to implement the methods performed by the network devices, for example: one or more microprocessors DSP, or one or more field programmable gate arrays FPGA, or the like. The storage element may be a memory or a combination of a plurality of storage elements.

The memory 75 may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The nonvolatile Memory may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable PROM (EEPROM), or a flash Memory. The volatile Memory may be a Random Access Memory (RAM) which serves as an external cache. By way of example and not limitation, many forms of RAM are available, such as Static random access memory (Static RAM, SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (ddr Data Rate SDRAM), Enhanced SDRAM (ESDRAM), synchlronous DRAM (SLDRAM), and Direct Rambus RAM (DRRAM). The memory 75 described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

Specifically, the network device of the embodiment of the present invention further includes: a computer program stored on the memory 75 and executable on the processor 74, the processor 74 calling the computer program in the memory 75 to execute the method performed by each module shown in fig. 2, 4 or 6.

The network equipment in the embodiment of the invention acquires the operation request information of the PDU session information of the grouped data unit; and carrying out PDU session processing according to the operation request information. Therefore, through the mutual cooperation among the terminal, the first network unit and the second network unit, when the connection of the suspended terminal is recovered, the recovery of the PDU session can be carried out according to the PDU session information needing to be recovered in the operation request information, thereby saving the resources of the wireless access network and reducing the signaling overhead.

The above embodiment describes the session control method of the present invention from the network device side, and the following embodiment further describes the session control method of the terminal side with reference to the drawings.

As shown in fig. 8, the session control method according to the embodiment of the present invention is applied to a terminal side, and specifically includes the following steps:

step 81: operation request information for packet data unit, PDU, session information is sent to the first network element.

Wherein the operation request information may include at least one of: PDU session information requested by the terminal, PDU session information requested to be recovered by the second network and PDU session information requested to be recovered by the first network.

Step 82: and receiving PDU session operation response information sent by the first network unit according to the operation request information.

Optionally, the PDU session operation response information includes: acknowledging recovery and/or acknowledging unrecoverable PDU session information.

Step 83: and processing the PDU session according to the PDU session operation response information.

Specifically, the step of processing the PDU session according to the information confirming recovery and/or confirming unrecoverable PDU session may include at least one of: recovering the PDU session confirmed to be recovered according to the information of the PDU session confirmed to be recovered; and releasing or suspending the unrecoverable PDU session according to the information for confirming the unrecoverable PDU session.

In one embodiment, step 81 may be preceded by: and generating PDU session information requesting recovery. After generating the PDU session information requesting recovery, the PDU session information requesting recovery is sent to the first network element, and specifically may be sent by an RRC recovery request.

In one embodiment, step 81 may be preceded by: and receiving PDU session information which is sent by the first network unit and requests to recover. Specifically, the PDU session information sent by the first network element requesting recovery may be received through paging.

In one embodiment, step 81 may be preceded by: and receiving the PDU session information which is sent by the second network unit and requests to be recovered through the first network unit. Specifically, the PDU session information sent by the first network element and requested to be recovered by the second network element may be received through paging.

Optionally, before step 81, the method may further include: and receiving PDU session information which is requested to be recovered by the second unit through the notification message.

Optionally, after step 81, the method may further include: optionally, after the step of processing the PDU session according to the information confirming recovery or confirming the unrecoverable PDU session, the method may further include: and generating PDU session recovery result information of the terminal after the PDU session processing and feeding the PDU session recovery result information back to the first network unit. Wherein, the PDU recovery result information of the terminal may include at least one of the following information: the terminal recovers the successful PDU session information, the terminal recovers the failed PDU session information, the terminal releases the successful PDU session information and the terminal suspends the PDU session information.

It is worth pointing out that the PDU session information may include at least one of the following information: PDU conversation identification information, recovery indication information, suspension indication information, release indication information, PDU conversation identification bitmap information and QoS flow information in the PDU conversation. Bit positions in the PDU session identification bitmap represent PDU session identifications, and a bit position indicates whether recovery indicates whether the PDU session represented by the bit is recovered.

The first network element may comprise at least one of: the system comprises wireless access network equipment, a wireless access network node, a wireless access network functional unit, a centralized unit CU, a distributed unit DU, a base station, an eNB, a gNB, an N3IWF, an access control node AC, access point AP equipment or a wireless local area network WLAN node;

the second network element may comprise at least one of: the system comprises core network equipment, core network nodes, a core network function unit, a mobile management entity MME, an access management function AMF, a session management function SMF, a serving gateway SGW, a PDN gateway PGW and a user plane function UPF.

The embodiment of the invention can recover the PDU conversation according to the requirement when the suspended terminal recovers the connection through the cooperation of the terminal, the first network unit and the second network unit, thereby saving the resources of the wireless access network and reducing the signaling expense.

The above embodiments describe the session control method in different scenarios, and the following describes a terminal corresponding to the session control method with reference to the accompanying drawings.

As shown in fig. 9, a terminal 900 according to an embodiment of the present invention can implement details of the method for sending the packet data unit PDU session information requesting to be recovered to the first network element in the foregoing embodiment, and achieve the same effect, where the terminal 900 may include the following functional modules:

a third sending module 910, configured to send operation request information of packet data unit PDU session information to the first network element;

a second receiving module 920, configured to receive PDU session recovery result information of the first network element sent by the first network element according to the operation request information;

the fourth processing module 930 may be configured to process the PDU session according to the PDU session recovery result information of the first network element.

Wherein the operation request information includes at least one of:

PDU session information requested by the terminal, PDU session information requested to be recovered by the second network and PDU session information requested to be recovered by the first network.

Wherein, the terminal 900 may further include at least one of:

a second generating module, configured to generate PDU session information requesting recovery;

a third receiving module, configured to receive PDU session information that is sent by the first network element and requests to be recovered;

the fourth sending module may be configured to receive, by the first network element, PDU session information that is sent by the second network element and that requests recovery.

The PDU session recovery result information of the first network element may include: confirming recovery and/or confirming PDU session information which cannot be recovered;

the fourth processing module 930 may include at least one of:

and the thirteenth processing submodule can be used for processing the PDU session according to the information for confirming recovery and/or confirming the PDU session which cannot be recovered.

Optionally, the thirteenth processing sub-module may be configured to: recovering the PDU session confirmed to be recovered according to the information of the PDU session confirmed to be recovered;

and releasing or suspending the unrecoverable PDU session according to the information for confirming the unrecoverable PDU session.

The fourth processing module 930 may further include:

the feedback sub-module can be used for generating PDU session recovery result information of the terminal after the PDU session processing and feeding the PDU session recovery result information back to the first network unit; wherein, the PDU recovery result information of the terminal may include at least one of the following information: the terminal recovers the successful PDU session information, the terminal recovers the failed PDU session information, the terminal releases the successful PDU session information and the terminal suspends the PDU session information.

Wherein the PDU session information may include at least one of the following information: PDU conversation identification information, recovery indication information, suspension indication information, release indication information, PDU conversation identification bitmap information and QoS flow information in the PDU conversation.

Wherein the first network element may comprise at least one of: the system comprises wireless access network equipment, a wireless access network node, a wireless access network functional unit, a centralized unit CU, a distributed unit DU, a base station, an eNB, a gNB, an N3IWF, an access control node AC, access point AP equipment or a wireless local area network WLAN node;

It is worth pointing out that, in the embodiment of the present invention, through the cooperation of the terminal, the first network element and the second network element, when the connection of the suspended terminal is resumed, the PDU session can be resumed as needed, thereby saving the resources of the radio access network and reducing the signaling overhead.

It should be noted that the division of the modules of the network device and the terminal is only a logical division, and the actual implementation may be wholly or partially integrated into one physical entity, or may be physically separated. And these modules can be realized in the form of software called by processing element; or may be implemented entirely in hardware; and part of the modules can be realized in the form of calling software by the processing element, and part of the modules can be realized in the form of hardware. For example, the determining module may be a processing element separately set up, or may be implemented by being integrated in a chip of the apparatus, or may be stored in a memory of the apparatus in the form of program code, and the function of the determining module is called and executed by a processing element of the apparatus. Other modules are implemented similarly. In addition, all or part of the modules can be integrated together or can be independently realized. The processing element here may be an integrated circuit with signal processing capabilities. In implementation, each step of the above method or each module above may be implemented by an integrated logic circuit of hardware in a processor element or an instruction in the form of software.

For example, the above modules may be one or more integrated circuits configured to implement the above methods, such as: one or more Application Specific Integrated Circuits (ASICs), or one or more microprocessors (DSPs), or one or more Field Programmable Gate Arrays (FPGAs), among others. For another example, when one of the above modules is implemented in the form of a Processing element scheduler code, the Processing element may be a general-purpose processor, such as a Central Processing Unit (CPU) or other processor capable of calling program code. For another example, these modules may be integrated together and implemented in the form of a system-on-a-chip (SOC).

To better achieve the above object, further, fig. 10 is a schematic diagram of a hardware structure of a terminal implementing various embodiments of the present invention, where the terminal 100 includes, but is not limited to: radio frequency unit 101, network module 102, audio output unit 103, input unit 104, sensor 105, display unit 106, user input unit 107, interface unit 108, memory 109, processor 1010, and power source 1011. Those skilled in the art will appreciate that the terminal configuration shown in fig. 10 is not intended to be limiting, and that the terminal may include more or fewer components than shown, or some components may be combined, or a different arrangement of components. In the embodiment of the present invention, the terminal includes, but is not limited to, a mobile phone, a tablet computer, a notebook computer, a palm computer, a vehicle-mounted terminal, a wearable device, a pedometer, and the like.

The radio frequency unit 101 may be configured to send, under the control of the processor 1010, packet data unit PDU session information requesting recovery to the first network unit.

Wherein the PDU session information requested to be recovered may include at least one of:

Specifically, the processor 1010 may be configured to, before sending the packet data unit, PDU, session information requesting recovery to the first network element, perform at least one of:

generating PDU session information requesting recovery;

receiving PDU session information which is sent by a first network unit and requests for recovery;

receiving, by a first network element, PDU session information requesting recovery sent by a second network element;

receiving PDU session information which is sent by a first network unit and requests for recovery through paging;

receiving PDU session information which is sent by a first network unit and is requested to be recovered by a second network unit through paging;

and receiving PDU session information which is requested to be recovered by the second unit through the notification message.

Specifically, processor 1010 may also be configured to: receiving recovery-confirmed PDU session information and/or recovery-unrecoverable PDU session information fed back by the first network unit;

and processing the PDU session according to the information of the PDU session which confirms recovery or cannot be recovered.

Specifically, processor 1010 may also be configured to: recovering the recovered PDU session according to the information of the recovered PDU session;

Specifically, processor 1010 is further configured to: generating PDU conversation recovery result information of the terminal after the PDU conversation processing and feeding back the PDU conversation recovery result information to the first network unit; wherein, the PDU recovery result information of the terminal may include at least one of the following information: the terminal recovers the successful PDU session information, the terminal recovers the failed PDU session information, the terminal releases the successful PDU session information and the terminal suspends the PDU session information.

Specifically, the PDU session information may include at least one of the following information: PDU conversation identification information, recovery indication information, suspension indication information, release indication information, PDU conversation identification bitmap information and QoS flow information in the PDU conversation.

Specifically, the first network element may include at least one of: the system comprises wireless access network equipment, a wireless access network node, a wireless access network functional unit, a centralized unit CU, a distributed unit DU, a base station, an eNB, a gNB, an N3IWF, an access control node AC, access point AP equipment or a wireless local area network WLAN node;

Specifically, the terminal generates a PDU session recovery requirement;

the terminal sends PDU session information requesting for recovery;

the terminal sends the PDU session information requesting recovery to the first network element.

Further, the terminal receives PDU session information for confirming recovery;

and the terminal performs PDU recovery operation according to the PDU session information confirmed to be recovered.

The terminal also transmits PDU session information requesting recovery before receiving the PDU session information confirming recovery.

It should be understood that, in the embodiment of the present invention, the radio frequency unit 101 may be used for receiving and sending signals during a message transmission or call process, and specifically, receives downlink data from a base station and then processes the received downlink data to the processor 1010; in addition, the uplink data is transmitted to the base station. Typically, radio frequency unit 101 includes, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, and the like. In addition, the radio frequency unit 101 can also communicate with a network and other devices through a wireless communication system.

The terminal provides wireless broadband internet access to the user through the network module 102, such as helping the user send and receive e-mails, browse web pages, access streaming media, and the like.

The audio output unit 103 may convert audio data received by the radio frequency unit 101 or the network module 102 or stored in the memory 109 into an audio signal and output as sound. Also, the audio output unit 103 may also provide audio output related to a specific function performed by the terminal 100 (e.g., a call signal reception sound, a message reception sound, etc.). The audio output unit 103 includes a speaker, a buzzer, a receiver, and the like.

The input unit 104 is used to receive an audio or video signal. The input Unit 104 may include a Graphics Processing Unit (GPU) 1041 and a microphone 1042, and the Graphics processor 1041 processes image data of a still picture or video obtained by an image capturing device (e.g., a camera) in a video capturing mode or an image capturing mode. The processed image frames may be displayed on the display unit 106. The image frames processed by the graphic processor 1041 may be stored in the memory 109 (or other storage medium) or transmitted via the radio frequency unit 101 or the network module 102. The microphone 1042 may receive sound and may be capable of processing such sound into audio data. The processed audio data may be converted into a format output transmittable to a mobile communication base station via the radio frequency unit 101 in case of a phone call mode.

The terminal 100 also includes at least one sensor 105, such as a light sensor, motion sensor, and other sensors. Specifically, the light sensor includes an ambient light sensor that can adjust the brightness of the display panel 1061 according to the brightness of ambient light, and a proximity sensor that can turn off the display panel 1061 and/or a backlight when the terminal 100 is moved to the ear. As one of the motion sensors, the accelerometer sensor can detect the magnitude of acceleration in each direction (generally three axes), detect the magnitude and direction of gravity when stationary, and can be used to identify the terminal posture (such as horizontal and vertical screen switching, related games, magnetometer posture calibration), vibration identification related functions (such as pedometer, tapping), and the like; the sensors 105 may also include fingerprint sensors, pressure sensors, iris sensors, molecular sensors, gyroscopes, barometers, hygrometers, thermometers, infrared sensors, etc., which are not described in detail herein.

The display unit 106 is used to display information input by a user or information provided to the user. The Display unit 106 may include a Display panel 1061, and the Display panel 1061 may be configured in the form of a Liquid Crystal Display (LCD), an Organic Light-Emitting Diode (OLED), or the like.

The user input unit 107 may be used to receive input numeric or character information and generate key signal inputs related to user settings and function control of the terminal. Specifically, the user input unit 107 includes a touch panel 1071 and other input devices 1072. Touch panel 1071, also referred to as a touch screen, may collect touch operations by a user on or near the touch panel 1071 (e.g., operations by a user on or near touch panel 1071 using a finger, stylus, or any suitable object or attachment). The touch panel 1071 may include two parts of a touch detection device and a touch controller. The touch detection device detects the touch direction of a user, detects a signal brought by touch operation and transmits the signal to the touch controller; the touch controller receives touch information from the touch sensing device, converts the touch information into touch point coordinates, sends the touch point coordinates to the processor 1010, and receives and executes commands sent by the processor 1010. In addition, the touch panel 1071 may be implemented in various types, such as a resistive type, a capacitive type, an infrared ray, and a surface acoustic wave. In addition to the touch panel 1071, the user input unit 107 may include other input devices 1072. Specifically, other input devices 1072 may include, but are not limited to, a physical keyboard, function keys (e.g., volume control keys, switch keys, etc.), a trackball, a mouse, and a joystick, which are not described in detail herein.

Further, the touch panel 1071 may be overlaid on the display panel 1061, and when the touch panel 1071 detects a touch operation thereon or nearby, the touch panel 1071 transmits the touch operation to the processor 1010 to determine the type of the touch event, and then the processor 1010 provides a corresponding visual output on the display panel 1061 according to the type of the touch event. Although in fig. 10, the touch panel 1071 and the display panel 1061 are two independent components to implement the input and output functions of the terminal, in some embodiments, the touch panel 1071 and the display panel 1061 may be integrated to implement the input and output functions of the terminal, and is not limited herein.

The interface unit 108 is an interface for connecting an external device to the terminal 100. For example, the external device may include a wired or wireless headset port, an external power supply (or battery charger) port, a wired or wireless data port, a memory card port, a port for connecting a device having an identification module, an audio input/output (I/O) port, a video I/O port, an earphone port, and the like. The interface unit 108 may be used to receive input (e.g., data information, power, etc.) from an external device and transmit the received input to one or more elements within the terminal 100 or may be used to transmit data between the terminal 100 and the external device.

The memory 109 may be used to store software programs as well as various data. The memory 109 may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application program required by at least one function (such as a sound playing function, an image playing function, etc.), and the like; the storage data area may store data (such as audio data, a phonebook, etc.) created according to the use of the cellular phone, and the like. Further, the memory 109 may include high speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other volatile solid state storage device.

The processor 1010 is a control center of the terminal, connects various parts of the entire terminal using various interfaces and lines, and performs various functions of the terminal and processes data by operating or executing software programs and/or modules stored in the memory 109 and calling data stored in the memory 109, thereby performing overall monitoring of the terminal. Processor 1010 may include one or more processing units; preferably, the processor 1010 may integrate an application processor, which mainly handles operating systems, user interfaces, application programs, etc., and a modem processor, which mainly handles wireless communications. It will be appreciated that the modem processor described above may not be integrated into processor 1010.

The terminal 100 may also include a power source 1011 (e.g., a battery) for powering the various components, and preferably, the power source 1011 may be logically coupled to the processor 1010 via a power management system that may be configured to manage charging, discharging, and power consumption.

In addition, the terminal 100 includes some functional modules that are not shown, and thus, the detailed description thereof is omitted.

Preferably, an embodiment of the present invention further provides a terminal, including a processor 1010, a memory 109, and a computer program stored in the memory 109 and capable of running on the processor 1010, where the computer program is executed by the processor 1010 to implement the processes of the above-mentioned session control method embodiment, and can achieve the same technical effects, and in order to avoid repetition, details are not described here again. A terminal may be a wireless terminal or a wired terminal, and a wireless terminal may be a device providing voice and/or other service data connectivity to a user, a handheld device having a wireless connection function, or other processing devices connected to a wireless modem. A wireless terminal, which may be a mobile terminal such as a mobile telephone (or "cellular" telephone) and a computer having a mobile terminal, e.g., a portable, pocket, hand-held, computer-included, or vehicle-mounted mobile device, may communicate with one or more core networks via a Radio Access Network (RAN), and may exchange language and/or data with the RAN. For example, devices such as Personal Communication Service (PCS) phones, cordless phones, Session Initiation Protocol (SIP) phones, Wireless Local Loop (WLL) stations, and Personal Digital Assistants (PDAs) are used. A wireless Terminal may also be referred to as a system, a Subscriber Unit (Subscriber Unit), a Subscriber Station (Subscriber Station), a Mobile Station (Mobile), a Remote Station (Remote Station), a Remote Terminal (Remote Terminal), an Access Terminal (Access Terminal), a User Terminal (User Terminal), a User Agent (User Agent), and a User Device or User Equipment (User Equipment), which are not limited herein.

The embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the computer program implements each process of the above-mentioned session control method embodiment, and can achieve the same technical effect, and in order to avoid repetition, details are not repeated here. The computer-readable storage medium may be a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk.

In the above, different processing manners of the session control method according to the embodiment of the present invention are introduced from the first network element, the second network element, and the terminal, and the following embodiment will further describe the session control method in different scenarios by taking PDU session recovery operation as an example.

As shown in fig. 11, the network architecture of the embodiment of the present invention includes: the terminal, a first network element (taking a radio access network as an example), and a second network element (taking a core network as an example), where the core network includes an access management function AMF, a session management function SMF, and a user plane function. The wireless access network receives PDU session information which is sent by the UE and requires to be recovered, and the recovery is carried out according to the PDU session which is required to be recovered by the UE, wherein the wireless access network recovers all PDU sessions of the UE under the condition that the PDU session which is required by the UE is prioritized, and then the wireless access network sends the PDU session information which is required to be recovered by the UE to a core network.

First embodiment

And the UE sends the PDU session information requesting recovery to the wireless access network, and the wireless access network can recover the PDU session according to the recovery request of the UE and inform the core network of the result of the recovery of the PDU session to recover the PDU session. And the core network receives the PDU session recovery result sent by the wireless access network to recover the PDU session and informs the wireless access network of the PDU session recovery result of the core network. And the UE carries out PDU session recovery according to the PDU session confirmed to be recovered by the wireless access network.

Specifically, the embodiment is a recovery operation, the PDU session recovery sequence is that the radio access network and the UE recover first, and the core network side recovers the PDU session according to the PDU session recovery result of the UE and the radio access network. The method has the advantage that the UE can send uplink data after the PDU session between the UE and the wireless access network side is recovered. In this embodiment, the radio access network performs PDU session recovery according to the PDU session information that the UE requests to recover. As shown in fig. 12, this embodiment specifically includes the following steps:

step 121: the UE sends an RRC recovery request to the radio access network. Here, the RRC recovery request corresponds to the operation request information. Optionally, at least one of the following may be indicated in the operation request information: information of the PDU session requested to be recovered.

For PDU sessions not requesting to resume, the radio access network may continue to suspend or release.

The radio access network can perform a PDU session recovery operation according to the request of the UE, including at least one of:

-restoring the context of the specified PDU session,

-recovering radio bearers specifying a PDU session mapping (e.g. Data Resource Bearers (DRBs), etc.),

-assigning or mapping radio bearers (such as DRBs) for a specified PDU session,

-restoring the connection between the radio access network and the core network with respect to the UE.

In some embodiments, not every UE-requested PDU session can be allocated radio resources due to radio resource scarcity. Therefore, the radio access network may transmit information confirming the resumed PDU session to the UE.

Additionally, at least one of the following may be indicated in the request: PDU session information requesting suspension, PDU session information requesting release.

Step 122: the radio access network sends RRC recovery to the UE, where the RRC recovery carries PDU session recovery result information, and optionally, at least one of the following RRC recovery indications: confirming the recovered PDU session information and confirming the PDU session information which can not be recovered.

And the UE carries out PDU session recovery according to the indicated PDU session information confirmed to be recovered and/or PDU session information confirmed to be unrecoverable.

Step 123: the UE sends an RRC recovery complete to the radio access network. Optionally, at least one of the following may be indicated in the RRC recovery complete: and the UE recovers the information of the successful PDU session and the UE side recovers the information of the failed PDU session.

In some embodiments, the UE side may not be able to resume the PDU session all the time due to unpredictable reasons. The UE is required to return PDU session recovery result information of the UE to confirm the recovery result of the PDU session on the UE.

Step 124: the radio access network sends a recovery request to the access mobility management function.

Optionally, the recovery request carries PDU session recovery result information of the radio access network, and may specifically indicate at least one of the following: and recovering the information of the successful PDU session and recovering the information of the failed PDU session. And the PDU session information which is successfully recovered indicates that the wireless access network confirms the PDU session information recovered on the UE and the wireless access network according to the UE request.

Step 125: the access mobility management function sends a recovery request to the session management function of the PDU session of the UE.

Optionally, at least one of the following may be indicated in the request: and recovering the information of the successful PDU session and recovering the information of the failed PDU session. And the PDU session information which is successfully recovered indicates that the wireless access network confirms the PDU session information recovered on the UE and the wireless access network according to the UE request.

Wherein,

-for recovering a successful PDU session for a UE, the session management function may perform at least one of: recovering the PDU session context of the UE, sending a downlink transmission address of the PDU session of the UE (namely a transmission address distributed by a wireless access network for the PDU session of the UE) to a user plane function, activating the PDU session of the UE to the user plane function, and setting the PDU session state of the UE to be activated.

-for recovering a PDU session of a failed UE and/or a PDU session of a UE requesting suspension, the session management function may perform at least one of: continuing to suspend the PDU session of the UE, deleting the PDU session of the UE and requesting the user plane function to delete the PDU session of the UE. In some embodiments, whether to continue suspending or delete a PDU session for a recovery failed UE depends on the reason for the recovery failure. Such as recovery failure due to insufficient radio access network side resources, may continue to be suspended. For example, the PDU session description information that the PDU session requested to be recovered is unknown is inconsistent and should be deleted.

-for a PDU session of a UE requesting suspension, the session management function may perform at least one of: continuing to suspend the PDU session of the UE.

-for PDU session information requesting release, the session management function may perform at least one of: and deleting the PDU session of the UE and requesting the user plane function to delete the PDU session of the UE.

Step 126: and the session management function sends a recovery response to the access mobility management function, wherein the recovery response corresponds to the PDU session recovery result information of the second network unit. Optionally, at least one of the following may be indicated in the request: and recovering the information of the successful PDU session and recovering the information of the failed PDU session. The recovery successful PDU session information indicates that the session management function recovers the successful PDU session information on the core network side.

Step 127: and the access mobile management function sends a recovery response to the wireless access network, wherein the recovery response corresponds to the PDU session recovery result information of the second network unit. Optionally, at least one of the following may be indicated in the request: and recovering the information of the successful PDU session and recovering the information of the failed PDU session. The recovery successful PDU session information indicates that the session management function recovers the successful PDU session information on the core network side.

-for information on recovery of failed PDU sessions, the radio access network may perform one of: suspending a PDU session context, suspending a mapped radio bearer context for a PDU session, releasing bearer resources, saving an uplink transport address for the PDU session (i.e. a transport address allocated by the user plane function for the PDU session of the UE), setting the PDU session state of the UE to suspended, requesting the UE to suspend the PDU session, deleting the PDU session context, requesting the UE to delete the PDU session.

Second embodiment

This embodiment is a restore operation. The recovery sequence is that the wireless access network side and the UE recover the PDU session first; and the core network side recovers the PDU session according to the PDU session recovery result of the UE and the wireless access side. The method has the advantage that the UE can send uplink data after the PDU session between the UE and the wireless access network is recovered.

In this embodiment, the network recovers according to the PDU session information requested by the UE and the PDU session information requested by the second network element, such as the PDU session information required for data transmission. As shown in fig. 13, this embodiment specifically includes the following steps:

step 131: the UE sends an RRC recovery request to the radio access network. Optionally, at least one of the following may be indicated in the request: information of the PDU session requested to be recovered.

-restoring the context of the specified PDU session,

-recovering a radio bearer (e.g. DRB) specifying a PDU session mapping,

-assigning or mapping radio bearers (such as DRBs) for a specified PDU session,

In some embodiments, not every UE-requested PDU session can be allocated radio resources due to radio resource scarcity. Therefore, the radio access network needs to be able to send information to the UE confirming the resumed PDU session.

Step 132: the radio access network sends an RRC recovery to the UE, optionally, the RRC recovery indicates at least one of the following: confirming the recovered PDU session information and confirming the unrecoverable PDU session information.

And the UE carries out PDU session recovery according to the indicated information for confirming the recovered PDU session and/or the information for confirming the unrecoverable PDU session.

Step 133: the UE sends an RRC recovery complete to the radio access network. Optionally, at least one of the following may be indicated in the RRC recovery complete: and the UE recovers the information of the successful PDU session and the UE side recovers the information of the failed PDU session.

In some embodiments, the UE side may not be able to resume the PDU session all the time due to unpredictable reasons. The UE is required to return the PDU session recovery result of the UE.

Step 134: the radio access network sends a recovery request to the access mobility management function.

Step 135: the access mobility management function sends a recovery request to the session management function of the PDU session of the UE.

For PDU sessions with a downstream data transfer need (e.g. notified by downstream data), the session management function may perform at least one of: and recovering the PDU session of the UE, and sending information about the PDU session requiring recovery.

Step 136: the session management function sends a recovery response to the access mobility management function. Optionally, at least one of the following may be indicated in the request: information of a successful recovery PDU session, information of a failed recovery PDU session, and information of a recovery PDU session requested by a core network. The recovery successful PDU session information indicates that the session management function recovers the successful PDU session information on the core network side. The information of the PDU session requiring recovery indicates that the session management function additionally requires information of the PDU session requiring recovery.

Step 137: the access mobility management function sends a recovery response to the radio access network. Optionally, at least one of the following may be indicated in the request: information of a successful recovery PDU session, information of a failed recovery PDU session, and information of a recovery PDU session requested by a core network. The recovery successful PDU session information indicates that the session management function recovers the successful PDU session information on the core network side.

-information of PDU sessions requiring recovery, the radio access network may perform one of: and recovering the PDU session of the UE and requesting the UE to recover the PDU session. The UE may be requested by an RRC reconfiguration message containing a PDU session specifying recovery.

Based on the information of the PDU session that requires recovery, the radio access network may perform one of:

-restoring the context of the specified PDU session,

-recovering a radio bearer (e.g. DRB) specifying a PDU session mapping,

-assigning or mapping radio bearers (such as DRBs) for a specified PDU session,

-sending information to the UE requiring a released/suspended PDU session.

Optionally, step 138: and the radio access network sends an RRC reconfiguration request message to the UE. Optionally, the message may include information of the PDU session that requires recovery.

And the UE carries out the recovery of the specified PDU session according to the received information of the PDU session required to be recovered.

Optionally, step 139: and the UE returns an RRC reconfiguration message response message to the radio access network. Optionally, at least one of the following may be indicated in the message: and the UE recovers the information of the successful PDU session and the UE side recovers the information of the failed PDU session.

Third embodiment

The embodiment is recovery operation, the PDU session recovery sequence is that the wireless access network side and the UE recover the PDU session first, and the core network side then recovers the PDU session according to the PDU session recovery result of the UE and the wireless access network and the PDU session information requested to be recovered by the UE. The method has the advantage that the UE can send uplink data after the PDU session between the UE and the wireless access network side is recovered. In this embodiment, the radio access network attempts to resume all the pending PDU sessions of the UE, and preferentially resumes the PDU session information requested by the UE when resources are insufficient. After the recovery request reaches the session management function, the session management function network recovers according to the PDU session information requested by the UE and the PDU session information with data transmission requirements. And the wireless access network suspends/releases the resources of the unneeded PDU session according to the information of the PDU session which is finally required to be recovered by the session management function. As shown in fig. 14, this embodiment specifically includes the following steps:

step 141: the UE sends an RRC recovery request to the radio access network. Optionally, the UE may indicate at least one of the following in step 141 or step 143: the UE requests information of the recovered PDU session.

Optionally, the radio access network performs a PDU session recovery operation, which may include at least one of:

-resuming the context of the PDU session of the suspended UE,

-resuming the radio bearer (e.g. DRB) of the pending UE PDU session mapping,

-allocating or mapping radio bearers (such as DRBs) for the PDU session of the UE,

In some embodiments, not every UE-requested PDU session can be allocated radio resources due to radio resource scarcity. The radio access network may preferentially resume the PDU session that the UE requested to be activated. In addition, the radio access network may transmit information confirming the resumed PDU session to the UE.

Step 142: the radio access network sends an RRC recovery to the UE, optionally, the RRC recovery indicates at least one of the following: confirming information of the recovered PDU session. In some embodiments, the PDU session information confirming the recovery may be a PDU session successfully recovered by the radio access side.

And the UE carries out PDU session recovery according to the indicated information for confirming the recovered PDU session.

Step 143: the UE sends an RRC recovery complete to the radio access network. Optionally, the PDU session recovery result information of the UE may be indicated in the RRC recovery completion, where the PDU session recovery result information includes at least one of: and the UE recovers the information of the successful PDU session and the UE side recovers the information of the failed PDU session.

In some embodiments, some PDU sessions may fail to recover on the UE side due to unpredictable reasons. For the UE side recovering the failed PDU session, the radio access network may perform one of the following: and releasing/suspending the PDU session, and requesting the core network to release/suspend the PDU session.

Step 144: the radio access network sends a recovery request to the access mobility management function.

Optionally, the request carries PDU session recovery result information of the radio access network and PDU session information that the terminal requests to recover, and may specifically indicate at least one of the following: information of a recovery successful PDU session, information of a recovery failed PDU session, and information of a PDU session requested to be recovered by the UE. And the PDU session information which is successfully recovered indicates that the wireless access network confirms the PDU session information recovered on the UE and the wireless access network according to the UE request.

Step 145: the access mobility management function sends a recovery request to the session management function of the PDU session of the UE.

Optionally, at least one of the following may be indicated in the request: information of a recovery successful PDU session, information of a recovery failed PDU session, and information of a PDU session requested to be recovered by the UE. The recovery successful PDU session information may be information that both the radio access network and the UE side recover the successful PDU session.

-for at least one of 1, the radio access network side resuming a successful PDU session and being a UE request activated PDU session and 2, the radio access network side resuming a successful PDU session and having a downlink data transfer requirement, the session management function may perform at least one of: recovering the PDU session context of the UE, sending a downlink transmission address of the PDU session of the UE (namely a transmission address distributed by a wireless access network for the PDU session of the UE) to a user plane function, activating the PDU session of the UE to the user plane function, and setting the PDU session state of the UE to be activated. In some embodiments, the PDU session with the downlink data transfer requirement is not necessarily in the PDU session that the UE requests to activate.

For a PDU session on the radio access network side that is successful but that is neither UE-requested active PDU session nor downlink data transfer required, the session management function may perform at least one of: suspending/releasing a PDU session, requesting a user plane management function to suspend/release a PDU session, requesting a radio access network to suspend/release a PDU session, requesting a UE to suspend/release a PDU session.

-for a PDU session of a UE requesting suspension, the session management function may perform at least one of: the PDU session continues to be suspended.

-for PDU session information requesting release, the session management function may perform at least one of: and releasing the PDU session, and requesting the user plane function to release the PDU session.

Step 146: the session management function sends a recovery response to the access mobility management function. Optionally, at least one of the following may be indicated in the request: information of a recovery successful PDU session, information of a recovery failed PDU session, information of a PDU session requiring release/suspension. The recovery successful PDU session information may indicate information that the core network side recovers the successful PDU session. The information of the PDU session required to be released/suspended indicates information of the PDU session required to be released/resumed by the session management function.

Step 147: the access mobility management function sends a recovery response to the radio access network. Optionally, at least one of the following may be indicated in the request: information of a recovery successful PDU session, information of a recovery failed PDU session, information of a PDU session requiring release/suspension. The recovery successful PDU session information may indicate information that the core network side recovers the successful PDU session.

Based on the information of the PDU session that requires release/suspension, the radio access network may perform one of:

-suspending/releasing the context of the specified PDU session,

-radio bearer context of PDU session mapping of the suspended UE,

-releasing the specified PDU session allocation or mapping radio bearer,

-sending information to the UE requiring a released/suspended PDU session

Optionally, step 148: the radio access network sends an RRC reconfiguration message to the UE. Optionally, the message includes information of the PDU session that requires release/suspension.

And the UE carries out suspension/release of the specified PDU session according to the received information which requires the release/suspension of the PDU session.

Fourth embodiment

The UE sends PDU session information requesting recovery to the wireless access network, the wireless access network sends the PDU session information requesting recovery to the core network, the core network carries out PDU session recovery according to the PDU session information requested by the UE and the PDU session information (namely the PDU session with downlink transmission requirement) requested to be recovered by the core network, and informs the wireless access network of the result of the PDU session recovery of the core network, and then the wireless access network carries out PDU session recovery according to the recovery result of the PDU session requested by the UE. As shown in fig. 15, this embodiment specifically includes the following steps:

step 151: the UE sends an RRC recovery request to the radio access network. Optionally, at least one of the following may be indicated in the request: the UE requests information of the recovered PDU session.

Step 152: the radio access network sends a recovery request to the access mobility management function.

Optionally, at least one of the following may be indicated in the request: the UE requests information of the recovered PDU session.

Step 153: the access mobility management function sends a recovery request to the session management function of the PDU session of the UE.

For PDU sessions that do not belong to the request to resume, the session management function may continue to suspend or release.

-for at least one of 1, a PDU session the UE requests to resume and 2, a PDU session with a downlink data transfer demand, the session management function may perform at least one of: recovering the PDU session context of the UE, sending a downlink transmission address of the PDU session of the UE (namely a transmission address distributed by a wireless access network for the PDU session of the UE) to a user plane function, activating the PDU session of the UE to the user plane function, and setting the PDU session state of the UE to be activated. In some embodiments, the PDU session required by the downlink data transfer is not necessarily in the PDU session requested to be activated by the UE.

Step 154: the session management function sends a recovery response to the access mobility management function. Optionally, at least one of the following may be indicated in the request: information of a recovery successful PDU session, information of a recovery failed PDU session, information of a PDU session requiring release/suspension. The recovery successful PDU session information indicates that the session management function recovers the successful PDU session information on the core network side. The information of the PDU session required to be released/suspended indicates information of the PDU session required to be released/resumed by the session management function.

Step 155: the access mobility management function sends a recovery response to the radio access network. Optionally, at least one of the following may be indicated in the request: information of a recovery successful PDU session, information of a recovery failed PDU session, information of a PDU session requiring release/suspension. The recovery successful PDU session information indicates that the session management function recovers the successful PDU session information on the core network side.

For the PDU session indicated to be successfully recovered, the radio access network performs a PDU session recovery operation, which may include at least one of:

-resuming the context of the PDU session of the suspended UE,

-resuming the radio bearer (e.g. DRB) of the pending UE PDU session mapping,

Based on the information of the PDU session that requires release/suspension, the radio access network may perform one of: suspending/releasing context of a specified PDU session, radio bearer context of PDU session mapping of a suspended UE, releasing specified PDU session allocation or mapping radio bearer, sending information to the UE requiring the release/suspension of PDU session

In some embodiments, not every UE-requested PDU session can be allocated radio resources due to radio resource scarcity. For a PDU session in which the recovery of the core network is successful but the recovery of the radio access network is failed, the radio access network performs at least one of: requesting a core network (such as access mobility management function, session management function, user plane function, etc.) to release/suspend a PDU session in which the core network recovery is successful but the radio access network recovery is failed

Step 156: the radio access network sends an RRC recovery to the UE, optionally, the RRC recovery indicates at least one of the following: confirming information of the recovered PDU session. In some embodiments, the information confirming the recovered PDU session comprises a PDU session that was successfully recovered by both the core network and the radio access network

Step 157: the UE sends an RRC recovery complete to the radio access network. Optionally, at least one of the following may be indicated in the RRC recovery complete: and the UE recovers the information of the successful PDU session and the UE side recovers the information of the failed PDU session.

Fifth embodiment

The embodiment is recovery operation, the PDU recovery sequence is still that the wireless access network side and the UE recover the PDU session first, and the core network side recovers the PDU session according to the PDU session recovery result of the UE and the wireless access network. In this embodiment, the radio access network attempts to resume all PDU sessions suspended by the UE. As shown in fig. 16, this embodiment specifically includes the following steps:

step 161: the UE sends an RRC recovery request to the radio access network.

The radio access network performs a PDU session recovery operation, which may include at least one of:

-resuming the context of the PDU session of the suspended UE,

-resuming the radio bearer (e.g. DRB) of the pending UE PDU session mapping,

Step 162: the radio access network sends an RRC recovery to the UE, optionally, the RRC recovery indicates at least one of the following: confirming information of the recovered PDU session. In some embodiments, the PDU session information confirming the recovery may be a PDU session successfully recovered by the radio access side.

Step 163: the UE sends an RRC recovery complete to the radio access network. Optionally, at least one of the following may be indicated in the RRC recovery complete: and the UE recovers the information of the successful PDU session and the UE side recovers the information of the failed PDU session.

Step 164: the radio access network sends a recovery request to the access mobility management function.

Step 165: the access mobility management function sends a recovery request to the session management function of the PDU session of the UE.

Optionally, at least one of the following may be indicated in the request: and recovering the information of the successful PDU session and recovering the information of the failed PDU session.

-for the radio access network side to resume a successful PDU session, the session management function may perform at least one of: recovering the PDU session context of the UE, sending a downlink transmission address of the PDU session of the UE (namely a transmission address distributed by a wireless access network for the PDU session of the UE) to a user plane function, activating the PDU session of the UE to the user plane function, and setting the PDU session state of the UE to be activated. In some embodiments, the PDU session with the downlink data transfer requirement is not necessarily in the PDU session that the UE requests to activate.

-for a radio access network side recovery of a PDU session of a failed UE, the session management function may perform at least one of: continuing to suspend the PDU session of the UE, deleting the PDU session of the UE and requesting the user plane function to delete the PDU session of the UE. In some embodiments, whether to continue suspending or delete a PDU session for a recovery failed UE depends on the reason for the recovery failure. Such as recovery failure due to insufficient radio access network side resources, may continue to be suspended. For example, the PDU session description information that the PDU session requested to be recovered is unknown is inconsistent and should be deleted.

Step 166: the session management function sends a recovery response to the access mobility management function. Optionally, at least one of the following may be indicated in the request: and recovering the information of the successful PDU session and recovering the information of the failed PDU session. The recovery successful PDU session information may indicate information that the core network side recovers the successful PDU session.

Step 167: the access mobility management function sends a recovery response to the radio access network. Optionally, at least one of the following may be indicated in the request: and recovering the information of the successful PDU session and recovering the information of the failed PDU session. The recovery successful PDU session information may indicate information that the core network side recovers the successful PDU session.

Optionally, step 168: the radio access network sends an RRC reconfiguration message to the UE. Optionally, the message includes information of the PDU session that requires release/suspension.

Sixth embodiment

In the 5G mobile communication system, the mobility management and the session management are further split and recombined, and the mobility management function in the MME is attributed to the AMF. The session management functions in the MME and the SGW and PGW are integrated into SMF, while the user plane functions in the SGW and PGW are integrated into AMF. For the user plane CIOT. Since there is no interface between the AMF and the UPF, if the UE context is only maintained on the AMF, but the UE context on the SMF is released, then the recovery on the UPF for the UE session cannot be supported.

This embodiment is a PDU session suspend procedure. As shown in fig. 17, this embodiment includes the steps of:

step 171: and the wireless access network decides to suspend the UE and sends a suspension request to the access mobility management function.

Step 172: the access mobility management function sends a suspend request to a session management function of the PDU session of the UE. The session management functions for PDU sessions for different UEs may be different.

The session management function may perform at least one of: the method comprises the steps of storing a PDU session context of the UE, storing a downlink transmission address of the PDU session of the UE (namely a transmission address distributed by a wireless access network for the PDU session of the UE), sending PDU session deactivation to a UPF (uplink packet radio network), and setting the PDU session state of the UE to be suspended.

Step 173: the session management function sends a suspend response to the access mobility management function.

The access mobility management function may perform one of: saving UE mobility context, saving UE session related information (PDU session identification, PDU session status, address of session management function, slice information)

Step 174: the access mobility management function sends a suspend response to the radio access network. Optionally, the response may include at least one of: and suspending the PDU session of the successful UE and suspending the PDU session of the failed UE.

The access mobility management function may wait until the session management function of the PDU session of all the UEs returns a suspend response and then initiate a suspend response to the radio access network.

The radio access network may perform one of: suspending a PDU session context of the UE, suspending a mapped radio bearer context of a PDU session of the UE, releasing bearer resources, saving an uplink transport address of the PDU session of the UE (i.e. a transport address allocated by the user plane function for the PDU session of the UE), setting the PDU session state of the UE to suspended, suspending the connection between the radio access network and the core network control plane (AMF, MME, etc.) in relation to the UE.

In some embodiments, the radio access network performs the suspend operation only for PDU sessions for which the suspension was specified to be successful.

In other embodiments, the radio access network releases for suspension of the failed PDU session.

Step 175: the radio access network sends an RRC suspend or RRC release message to the UE. Optionally, the message may include at least one of the following: information of a PDU session of the suspended UE, and information of a PDU session of the deleted UE.

The UE bottom layer (or AS layer) may perform a suspend operation, including at least one of: suspending a PDU session context of the UE, suspending a context of a mapped radio bearer of the PDU session of the UE, releasing bearer resources, setting a PDU session state of the UE to suspended, informing a higher layer (or NAS layer) of the UE to suspend the PDU session context of the UE, suspending a connection between a radio access network and a core network control plane (AMF, MME, etc.) with respect to the UE.

In some embodiments, the radio access network performs the suspend operation only for the PDU session designated to suspend.

In other embodiments, the radio access network releases the PDU session designated for deletion.

Seventh embodiment

When the terminal is in an idle state, the core network side may receive a downlink data notification about the terminal individual PDU session. For these sessions, recovery is required to transfer the data to the terminal. But there is no such information in the paging message. Then at the time of the terminal service request, it is not known that there is a PDU session for the downstream data transfer requirement, and the terminal requests less active PDU sessions. Similarly, for a terminal using the user plane CIOT, if the terminal is in an idle state, the paging message does not have information of a PDU session required for downlink data transmission, and if the UE requests to resume the PDU session as required, the UE may lack the PDU session.

The present embodiment is a paging operation/notification operation, and is applicable to a scenario in which a PDU session is processed based on a PDU session that a core network requests to resume. As shown in fig. 18, this embodiment includes the steps of:

step 181: when downlink data needs to be transmitted in the user plane function of the core network, PDU session information requesting recovery is determined, and the user plane function of the core network sends a downlink data notification to the SMF.

Step 182: the SMF sends the downlink data notification to the AMF.

Step 183 a: and the AMF sends a paging message or a notification message to the wireless access network, wherein the paging message carries PDU session information which is requested to be recovered by the core network.

Step 184: the radio access network forwards the paging message to the terminal.

Step 183 b: the AMF notifies the UE of the message. Wherein, the notification message may carry PDU session information requested to be recovered by the core network. In one embodiment, the UE is in an idle state in the 3GPP access network, but the UE is in a connected state in the non-3GPP access network. So the notification message containing the PDU session information requested to be recovered by the core network is sent to the UE through the 3GPP access network.

Step 185 a: after receiving the paging message, the terminal starts a PDU session recovery flow and sends a service request message to the core network. Wherein, the message may carry PDU session information requested to be recovered by the core network.

Or step 185 b: after receiving the paging message, the terminal starts a PDU session recovery flow and sends an RRC recovery request message to the wireless access network. Wherein, the message may carry PDU session information requested to be recovered by the core network.

It is worth noting that the acquisition involved in the embodiments of the present invention may be received, configured or known by itself. In some embodiments, the PDU session requiring data transmission may be a PDU session requiring downlink data transmission, or a PDU session receiving downlink data notification, etc. The PDU session requiring data transmission is not necessarily included in the PDU session information requesting recovery. Because the UE does not know that the network device has a PDU session for downstream data transmission when it sends information of the PDU session for which recovery is requested.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, a division of a unit is merely a logical division, and an actual implementation may have another division, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

Units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a U disk, a removable hard disk, a ROM, a RAM, a magnetic disk, or an optical disk.

Furthermore, it is to be noted that in the device and method of the invention, it is obvious that the individual components or steps can be decomposed and/or recombined. These decompositions and/or recombinations are to be regarded as equivalents of the present invention. Also, the steps of performing the series of processes described above may naturally be performed chronologically in the order described, but need not necessarily be performed chronologically, and some steps may be performed in parallel or independently of each other. It will be understood by those skilled in the art that all or any of the steps or elements of the method and apparatus of the present invention may be implemented in any computing device (including processors, storage media, etc.) or network of computing devices, in hardware, firmware, software, or any combination thereof, which can be implemented by those skilled in the art using their basic programming skills after reading the description of the present invention.

Thus, the objects of the invention may also be achieved by running a program or a set of programs on any computing device. The computing device may be a general purpose device as is well known. The object of the invention is thus also achieved solely by providing a program product comprising program code for implementing the method or device. That is, such a program product also constitutes the present invention, and a storage medium storing such a program product also constitutes the present invention. Obviously, the storage medium may be any known storage medium or any storage medium developed in the future. It is further noted that in the apparatus and method of the present invention, it is apparent that each component or step can be decomposed and/or recombined. These decompositions and/or recombinations are to be regarded as equivalents of the present invention. Also, the steps of executing the series of processes described above may naturally be executed chronologically in the order described, but need not necessarily be executed chronologically. Some steps may be performed in parallel or independently of each other.

The foregoing is a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and those improvements and modifications are also within the scope of the present invention.

Claims

1. A session control method is applied to a first network unit side, and is characterized by comprising the following steps:

carrying out PDU session processing according to the operation request information;

the PDU session information includes at least one of the following information: PDU conversation identification information, recovery indication information, suspension indication information, release indication information, PDU conversation identification bit map information and QoS flow information in the PDU conversation.

2. The session control method according to claim 1, wherein the step of performing PDU session processing according to the operation request information comprises at least one of:

when the operation request information is PDU session information which is requested to be recovered by the terminal, at least one of the following items is executed: carrying out recovery operation on the PDU session which is requested to be recovered by the terminal; restoring all PDU sessions suspended by the terminal; restoring all PDU sessions suspended by the terminal, and preferentially restoring the PDU session requested to be restored by the terminal when resources are insufficient;

when the operation request information is PDU session information requested to be released by a terminal, the PDU session requested to be released by the terminal is released;

and when the operation request information is PDU session information which is requested to be suspended by the terminal, the PDU session which is requested to be suspended by the terminal is subjected to suspension operation.

3. The session control method according to claim 2, wherein the step of performing a recovery operation on the PDU session comprises:

performing at least one of the following operations on the PDU session:

restoring the context of the PDU session;

recovering the radio bearer corresponding to the PDU session;

restoring the connection between the first network element and the second network element with respect to the terminal.

4. The session control method according to claim 2, wherein the step of performing PDU session processing according to the operation request information further comprises at least one of:

sending PDU session information confirming recovery and/or PDU session information confirming non-recovery to the terminal;

and the number of the first and second groups,

sending PDU session recovery result information of the first network unit to a second network unit; wherein the PDU session recovery result information of the first network element comprises at least one of the following information: recovering successful PDU session information, recovering failed PDU session information, requesting released PDU session information and requesting pending PDU session information.

5. The session control method according to claim 4, comprising at least one of:

the successfully recovered PDU session information is used for indicating that the terminal and the first network unit both recover the successful PDU session;

the recovery failed PDU session information is used for indicating the terminal or the first network unit to recover the failed PDU session;

the release-requested PDU session information is used for indicating at least one of the PDU session failed to be recovered by the terminal, the PDU session failed to be recovered by the first network unit and the PDU session requested to be released by the terminal;

the suspension-requested PDU session information is used for indicating at least one of the terminal recovering the failed PDU session, the first network unit recovering the failed PDU session and the terminal requesting the suspension of the PDU session;

the PDU session information confirming recovery is used for indicating at least one of the existence of a PDU session context, the existence of a PDU session capable of allocating or mapping radio bearer resources, and the existence of the PDU session capable of recovering confirmed by both the first network element and the second network element;

the confirming the unrecoverable PDU session comprises: at least one of a PDU session for which there is no PDU session context, a PDU session for which radio bearer resources cannot be allocated or mapped, a first network element acknowledging an unrecoverable PDU session, a second network element acknowledging an unrecoverable PDU session.

6. The session control method according to claim 4, wherein after the step of sending the PDU session information confirming recovery and/or PDU session information confirming non-recovery to the terminal, the method further comprises:

receiving PDU recovery result information of the terminal fed back by the terminal; wherein, the PDU recovery result information of the terminal includes: and the terminal recovers at least one of the successful PDU session information and the failed PDU session information.

7. The session control method according to claim 4, wherein the step of sending the PDU session recovery result information of the first network element to the second network element comprises:

sending a session operation request carrying PDU session recovery result information of the first network unit to a second network unit;

and receiving PDU session recovery result information of the second network unit, which is returned by the second network unit according to the session operation request.

8. The session control method according to claim 7, wherein after the step of receiving the PDU session recovery result information of the second network element returned by the second network element according to the session operation request, further comprising:

and processing the PDU session of the terminal according to the PDU session recovery result information of the second network unit.

9. The session control method according to claim 1, wherein the step of performing PDU session processing according to the operation request information comprises:

and when the operation request information comprises PDU session information which is requested to be recovered by the terminal, the PDU session information which is requested to be recovered by the terminal is sent to a second network unit.

10. The session control method according to claim 9, wherein the step of sending the PDU session information that the terminal requests to resume to the second network element is followed by further comprising:

receiving PDU conversation recovery result information of the second network unit fed back by the second network unit according to the PDU conversation information required to be recovered by the terminal;

11. The session control method according to claim 8 or 10, wherein the PDU session recovery result information of the second network element comprises at least one of the following information: the second network unit recovers the successful PDU session information, the second network unit recovers the failed PDU session information, the second network unit requests the recovery PDU session information, the second network unit requests the release PDU session information and the second network unit requests the suspension PDU session information.

12. The session control method according to claim 11, wherein the step of processing the PDU session of the terminal according to the PDU session recovery result information of the second network element comprises:

if the PDU session recovery result information of the second network unit is the PDU session information successfully recovered by the second network unit, when detecting that the PDU session successfully recovered by the second network unit can not be recovered at the first network unit or the terminal side, sending request information for requesting to release or suspend the PDU session to the second network unit;

if the PDU session recovery result information of the second network unit is PDU session information failed in recovery of the second network unit, at least one of the following operations is executed on the PDU session failed in recovery of the second network unit:

Suspending the second network element from recovering the context of the radio bearer corresponding to the failed PDU session,

Releasing the bearer resource corresponding to the PDU session failed to recover by the second network element,

Storing an uplink transport address of the PDU session for which recovery of the second network element failed,

Setting the PDU session status of the second network unit which fails to recover to be suspended,

Requesting the terminal to suspend the recovery of the failed PDU session by the second network element,

if the PDU session recovery result information of the second network unit is the PDU session information which is requested to be recovered by the second network unit, at least one of the following operations is executed to the PDU session which is requested to be recovered by the second network unit:

Restoring a connection with a second network element with respect to the terminal;

if the PDU session recovery result information of the second network element is the PDU session information requested to be released by the second network element, at least one of the following operations is performed on the PDU session requested to be released by the second network element:

if the PDU session recovery result information of the second network unit is the PDU session information which is requested to be suspended by the second network unit, at least one of the following operations is executed to the PDU session which is requested to be suspended by the second network unit:

Suspending the radio bearer context corresponding to the PDU session requested to be suspended by the second network element, releasing the radio bearer resource corresponding to the PDU session requested to be suspended by the second network element,

13. A network device, applied to a first network element side, comprising:

the first processing module is used for carrying out PDU session processing according to the operation request information;

14. The network device of claim 13, wherein the first processing module comprises at least one of:

a first processing sub-module, configured to, when the operation request information is PDU session information that the terminal requests to resume, perform at least one of the following: carrying out recovery operation on the PDU session which is requested to be recovered by the terminal; restoring all PDU sessions suspended by the terminal; restoring all PDU sessions suspended by the terminal, and preferentially restoring the PDU session requested to be restored by the terminal when resources are insufficient;

the second processing submodule is used for performing release operation on the PDU session requested to be released by the terminal when the operation request information is PDU session information requested to be released by the terminal;

and the third processing submodule is used for carrying out suspension operation on the PDU session requested to be suspended by the terminal when the operation request information is PDU session information requested to be suspended by the terminal.

15. The network device of claim 14, wherein the first processing module further comprises at least one of:

a first sending submodule, configured to send recovery confirmation and/or PDU session information that cannot be recovered confirmation to the terminal;

and the number of the first and second groups,

a second sending submodule, configured to send PDU session recovery result information of the first network element to a second network element; wherein the PDU session recovery result information of the first network element comprises at least one of the following information: recovering successful PDU session information, recovering failed PDU session information, requesting released PDU session information and requesting pending PDU session information.

16. The network device of claim 15, wherein the first processing module further comprises:

the first receiving submodule is used for receiving PDU recovery result information of the terminal fed back by the terminal; wherein, the PDU recovery result information of the terminal includes: and the terminal recovers at least one of the successful PDU session information and the failed PDU session information.

17. The network device of claim 13, wherein the first processing module further comprises:

and the fourth processing submodule is used for sending the PDU session information which is requested to be recovered by the terminal to the second network unit when the operation request information comprises the PDU session information which is requested to be recovered by the terminal.

18. A session control method is applied to a first network unit side, and is characterized by comprising the following steps:

acquiring operation request information of packet data unit PDU session information; the operation request information includes at least one of the following information: the second network unit requests the recovered PDU session information, the second network unit requests the release of the PDU session information and the second network unit requests the suspended PDU session information;

19. The session control method according to claim 18, wherein the step of performing PDU session processing according to the operation request information comprises at least one of:

when the operation request information is PDU session information which is requested to be recovered by a second network unit, recovering the PDU session which is requested to be recovered by the second network unit;

when the operation request information is PDU session information requested to be released by a second network unit, the PDU session requested to be released by the second network unit is released;

and when the operation request information is PDU session information which is requested to be suspended by the second network unit, the PDU session which is requested to be suspended by the second network unit is suspended.

20. The session control method according to claim 18 or 19, wherein the step of performing PDU session processing according to the operation request information further comprises:

and sending the operation request information to a terminal.

21. The session control method of claim 20, wherein the step of obtaining operation request information of Packet Data Unit (PDU) session information comprises:

receiving a paging message or a notification message sent by a second network unit;

the step of sending the operation request information to the terminal includes:

sending the received paging message or notification message to the terminal;

wherein the paging message or the notification message carries at least one of information indicating that the second network unit requests the PDU session to be resumed, information indicating that the second network unit requests the PDU session to be released, and information indicating that the second network unit requests the PDU session to be suspended.

22. A network device, applied to a first network element side, comprising:

the second acquisition module is used for acquiring the operation request information of the PDU session information; the operation request information includes at least one of the following information: the second network unit requests the recovered PDU session information, the second network unit requests the release of the PDU session information and the second network unit requests the suspended PDU session information;

the second processing module is used for carrying out PDU session processing according to the operation request information;

23. The network device of claim 22, wherein the second processing module comprises at least one of:

a fifth processing sub-module, configured to, when the operation request information is PDU session information that the second network unit requests to resume, perform a resume operation on the PDU session that the second network unit requests to resume;

a sixth processing sub-module, configured to, when the operation request information is PDU session information requested to be released by a second network element, perform a release operation on the PDU session requested to be released by the second network element;

and a seventh processing sub-module, configured to perform a suspend operation on the PDU session requested to be suspended by the second network unit when the operation request information is PDU session information requested to be suspended by the second network unit.

24. The network device of claim 22 or 23, wherein the second processing module further comprises:

25. A session control method is applied to a second network unit side, and is characterized by comprising the following steps:

26. The session control method according to claim 25, comprising at least one of:

the PDU session recovery result information of the first network element includes: recovering at least one of successful PDU session information, failed PDU session information, PDU session information requested to be released and PDU session information requested to be suspended;

the PDU session information which is requested to be recovered by the terminal is the PDU session information which is forwarded by the first network unit or sent by the terminal and is requested to be recovered by the terminal;

the PDU session information requested to be released by the terminal is the PDU session information requested to be released by the terminal and forwarded by the first network unit or sent by the terminal;

the PDU session information that the terminal requests to suspend is the PDU session information that the terminal requests to resume and is forwarded by the first network element or sent by the terminal.

27. The session control method according to claim 25 or 26, wherein the step of performing PDU session processing according to the operation request information comprises at least one of:

for the PDU session needing recovery operation, at least one of the following operations is executed:

restoring the context of the corresponding PDU session,

at least one of the PDU session indicated by the PDU session information requested to be released by the terminal and the PDU session indicated by the PDU session information requested to be released by the first network unit is subjected to the following operations: releasing the PDU session requested to be released by the terminal and/or the second network unit;

at least one of the PDU session indicated by the PDU session information requested to be suspended by the terminal and the PDU session indicated by the PDU session information requested to be suspended by the first network unit is subjected to the following operations: suspending the PDU session requested to be released by the terminal and/or a second network unit;

performing at least one of the following operations on the recovery-failed PDU session indicated by the PDU session recovery result information of the first network element:

suspending the context of a recovery failed PDU session,

Deleting the context of the PDU session with failed recovery,

Requesting the user plane functional entity to delete the PDU session failed to be recovered;

wherein, the PDU session needing recovery operation includes: the PDU session recovery result information of the first network unit indicates a PDU session that is successfully recovered, the PDU session indicated by the PDU session information that the terminal requests to recover, the PDU session indicated by the PDU session information that the third network unit requests to recover, the PDU session indicated by the PDU session information that has a requirement for downlink data transmission, the PDU session indicated by the PDU session information that receives a notification of downlink data, the PDU session recovery result information of the first network unit indicates a PDU session that is successfully recovered and that the third network unit requests to recover, the PDU session recovery result information of the first network unit indicates a PDU session that is successfully recovered and that has a requirement for downlink data transmission, the PDU session indicated by the PDU session recovery result information of the first network unit indicates a PDU session that is successfully recovered and that receives a notification of downlink data, and the PDU session recovery result information of the terminal requests to recover and that the PDU session recovery result information of the first network unit indicates a PDU session that is successfully recovered At least one item of (1).

28. The session control method according to claim 25, wherein after the step of performing PDU session processing according to the operation request information, the method further comprises:

generating PDU session recovery result information of the second network unit; wherein the PDU session recovery result information of the second network element comprises at least one of the following information: the second network unit recovers the successful PDU session information, the second network unit recovers the failed PDU session information, the second network unit requests the recovered PDU session information, the second network unit requests the released PDU session information, and the second network unit requests the suspended PDU session information;

and sending the PDU session recovery result information of the second network unit to the first network unit and/or sending the PDU session recovery result information of the second network unit to the terminal through the first network unit.

29. The session control method according to claim 28, comprising at least one of:

the PDU session information that the second network requests to resume includes: at least one item of PDU session information required by downlink data transmission, PDU session receiving downlink data notification and PDU session requested to be recovered by the third network unit;

the second network requests the PDU session information to be suspended including: at least one of the PDU session that the second network failed to recover, the PDU session that the first network unit succeeded in recovering but the second network failed to recover, and the PDU session that the first network unit and the terminal succeeded in recovering but the second network failed to recover;

the PDU session information requested to be released by the second network includes: at least one of the PDU session that failed to recover by the second network, the PDU session that succeeded in recovering by the first network element but failed to recover by the second network, and the PDU session that succeeded in recovering by the first network element and the terminal but failed to recover by the second network.

30. The session control method according to claim 25, wherein performing PDU session processing according to the operation request information comprises:

when the operation request information is at least one of the PDU session information requested to be recovered by the third network unit, the PDU session information requested to be released by the third network unit, the PDU session information requested to be suspended by the third network unit, the PDU session information required to be suspended by the third network unit and the PDU session information notified by the received downlink data, at least one of the PDU session information requested to be recovered by the third network unit, the PDU session information requested to be suspended by the third network unit, the PDU session information required to be suspended by the third network unit and the PDU session information notified by the received downlink data is sent to the first network unit through a paging request or a notification message.

31. A network device, applied to a second network element side, comprising:

the third processing module is used for carrying out PDU session processing according to the operation request information;

32. The network device of claim 31, wherein the third processing module comprises at least one of:

an eighth processing sub-module, configured to perform, on a PDU session that needs to be recovered, at least one of the following operations:

restoring the context of the corresponding PDU session,

a tenth processing sub-module, configured to perform the following operations on at least one of the PDU session indicated by the PDU session information requested to be suspended by the terminal and the PDU session indicated by the PDU session information requested to be suspended by the first network element: suspending the PDU session requested to be released by the terminal and/or a second network unit;

an eleventh processing sub-module, configured to perform, on a PDU session indicated by the PDU session recovery result information of the first network element, at least one of the following operations:

suspending the context of a recovery failed PDU session,

Deleting the context of the PDU session with failed recovery,

wherein, the PDU session needing recovery operation includes: the PDU session recovery result information of the first network unit indicates a PDU session that was successfully recovered, the PDU session indicated by the PDU session information that the terminal requested to be recovered, the PDU session indicated by the PDU session information that the third network unit requested to be recovered, the PDU session indicated by the PDU session information that had a requirement for downlink data transmission, the PDU session indicated by the PDU session information that received a downlink data notification, the PDU session recovery result information of the first network unit indicates a PDU session that was successfully recovered and that the third network unit requested to be recovered, the PDU session recovery result information of the first network unit indicates a PDU session that was successfully recovered and that had a requirement for downlink data transmission, the PDU session indicated by the PDU session recovery result information of the first network unit indicates a PDU session that was successfully recovered and that received a downlink data notification, and the PDU session recovery result information of the terminal requested to be recovered and that the PDU session recovery result information of the first network unit indicates a successful recovery At least one item of (1).

33. The network device of claim 31, wherein the network device further comprises:

a first generating module, configured to generate PDU session recovery result information of the second network element; wherein the PDU session recovery result information of the second network element comprises at least one of the following information: the second network unit recovers the successful PDU session information, the second network unit recovers the failed PDU session information, the second network unit requests the recovered PDU session information, the second network unit requests the released PDU session information, and the second network unit requests the suspended PDU session information;

and the second sending module is used for sending the PDU session recovery result information of the second network unit to the first network unit and/or sending the PDU session recovery result information to the terminal through the first network unit.

34. The network device of claim 31, wherein the third processing module further comprises:

a twelfth processing sub-module, configured to send, to the first network unit, at least one of the PDU session information requested to be restored by the third network unit, the PDU session information requested to be suspended by the third network unit, and the PDU session information notified by the downlink data, through a paging request or a notification message, at least one of the PDU session information requested to be restored by the third network unit, the PDU session information requested to be suspended by the third network unit, and the PDU session information notified by the downlink data.

35. A session control method applied to a terminal side is characterized by comprising the following steps:

receiving PDU session operation response information sent by the first network unit according to the operation request information;

carrying out PDU session processing according to the PDU session operation response information;

36. The session control method according to claim 35, wherein the operation request information includes at least one of:

PDU session information requested by the terminal, PDU session information requested to be recovered by the first network and PDU session information requested to be recovered by the second network.

37. The session control method of claim 35, further comprising, before the step of sending operation request information for packet data unit, PDU, session information to the first network element, at least one of:

generating PDU session information requesting recovery;

and receiving the PDU session information which is sent by the second network unit and requests to be recovered through the first network unit.

38. The session control method according to claim 35, wherein the PDU session operation response information comprises: confirming recovery and/or confirming PDU session information which cannot be recovered;

according to the PDU conversation operation response information, the PDU conversation processing step comprises:

and processing the PDU conversation according to the information of confirming the recovery and/or confirming the PDU conversation which can not be recovered.

39. The session control method according to claim 38, wherein the step of processing the PDU session according to the information confirming recovery and/or confirming unrecoverable PDU session comprises at least one of:

recovering the PDU session confirmed to be recovered according to the information of the PDU session confirmed to be recovered;

40. The session control method according to claim 38, wherein the step of processing the PDU session according to the information confirming recovery and/or confirming unrecoverable PDU session comprises:

generating PDU session recovery result information of the terminal after the PDU session processing and feeding back the PDU session recovery result information to the first network unit; wherein the PDU recovery result information of the terminal includes at least one of the following information: the terminal recovers the successful PDU session information, the terminal recovers the failed PDU session information, the terminal releases the successful PDU session information and the terminal hangs up PDU session information.

41. A terminal, comprising:

a second receiving module, configured to receive PDU session recovery result information of the first network element, where the PDU session recovery result information is sent by the first network element according to the operation request information;

a fourth processing module, configured to process the PDU session according to the PDU session recovery result information of the first network unit;

42. The terminal according to claim 41, characterized in that the terminal further comprises at least one of:

the second generation module is used for generating PDU session information requesting recovery;

and the fourth sending module is used for receiving the PDU session information which is sent by the second network unit and requests for recovery through the first network unit.

43. The terminal of claim 41, wherein the PDU session recovery result information of the first network element comprises: confirming recovery and/or confirming PDU session information which cannot be recovered;

the fourth processing module comprises:

and the thirteenth processing submodule is used for processing the PDU conversation according to the information of the PDU conversation which is confirmed to be recovered and/or can not be recovered.

44. The terminal of claim 41, wherein the fourth processing module further comprises:

the feedback submodule is used for generating PDU session recovery result information of the terminal after the PDU session processing and feeding the PDU session recovery result information back to the first network unit; wherein the PDU recovery result information of the terminal includes at least one of the following information: the terminal recovers the successful PDU session information, the terminal recovers the failed PDU session information, the terminal releases the successful PDU session information and the terminal hangs up PDU session information.

45. A network device comprising a processor, a memory, and a computer program stored on the memory and executable on the processor, the processor implementing the steps of the session control method according to any one of claims 1 to 12, 18 to 21, 25 to 30 when executing the computer program.

46. A terminal, characterized in that the terminal comprises a processor, a memory and a computer program stored on the memory and executable on the processor, the computer program, when executed by the processor, implementing the steps of the session control method according to any one of claims 35 to 40.

47. A computer-readable storage medium, characterized in that a computer program is stored thereon, which computer program, when being executed by a processor, realizes the steps of the session control method according to any one of claims 1 to 12, 18 to 21, 25 to 30, 35 to 40.