CN100527884C

CN100527884C - A method for switching among cells

Info

Publication number: CN100527884C
Application number: CNB2006100001122A
Authority: CN
Inventors: 谢明江; 王宗杰; 邱勇
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2006-01-04
Filing date: 2006-01-04
Publication date: 2009-08-12
Anticipated expiration: 2026-01-04
Also published as: CN1997204A

Abstract

This invention discloses one method to realize area switching, which comprises the following steps: setting control panel and user panel agreement in base station and network gate; after receiving message, network gate processes buffer on sent data for materials preparation by aim base station; aim base station preserves materials to establish new user interface and establishing materials to fulfill UE area switching and the gate execution path and sending the data to aim station for information transmission between aim base station and UE.

Description

A kind of method that realizes that the minizone is switched

Technical field

The present invention relates to the mobile communication technology field, relate to a kind of method that switch the minizone that in 3-G (Generation Three mobile communication system) (3GPP), realizes or rather.

Background technology

Universal mobile telecommunications system (UMTS) is to adopt Wideband Code Division Multiple Access (WCDMA) to insert the 3GPP system of (WCDMA) air interface technologies, also the UMTS system is called the WCDMA communication system usually.The UMTS system has adopted and the similar structure of second generation mobile communication system, comprises Radio Access Network (RAN, Radio Access Network) and core network (CN, Core Network) in the UMTS system equally.Wherein, RAN is used to handle all and wireless function associated, usually RAN is called land radio access web (UTRAN); CN then handles voice calls all in the UMTS system and is connected with data, and the exchange of realization and external network and routing function.CN is from being divided into circuit commutative field (CS, CircuitSwitched Domain) and packet-switched domain (PS, Packet Switched Domain) in logic.UTRAN, CN and subscriber equipment (UE, User Equipment) have constituted whole UMTS system together, and its system configuration as shown in Figure 1.

In the system shown in Figure 1, UTRAN generally includes one or several RNS (RNS).RNS is made up of a radio network controller (RNC) and one or more base station (NodeB).Among the UTRAN structure of RNS and with the annexation of CN as shown in Figure 2.

In the WCDMA system, a key technology of introducing is exactly a soft handover.The Ec/I0 of the Common Pilot Channel of UE measure neighbor cells (CPICH) channel according to measuring foundation and safeguarding a dedicated channel (DCH) Active Set, keeps soft handover with the sub-district in the DCH Active Set and is connected, and keeps transfer of data.Sub-district in the Active Set can belong to same base station, also can belong to different base station.Can only carry out the direct-cut operation of the minizone of different base station compares with the global system for mobile communications (GSM) in the second generation mobile communication, soft handover has improved the data smoothing transmission of user between different districts, make that professional service quality is relatively good, be not easy to cause loss of data.

Though current 3GPP system has had certain advantage, considers the competitiveness of future network, also need this system is done further evolution.The purpose of network evolution is to wish to provide a kind of low time delay, high data rate, high power system capacity and covering, low cost and complete IP-based network.

At present industry has proposed the candidate scheme of multiple network evolution, and that is relatively paid close attention to has as shown in Figure 3 a two-layer node framework.This framework has been realized UTRAN in the original WCDMA system and the function of CN by wireless station, edge (ERS, Edge Radio Station) and IP IAD (IAGW, IP Access GateWay).

In framework shown in Figure 3, ERS is the evolution at NodeB in the original system, and this ERS has the most of function of RNC in the original system, and has adopted the new physical-layer techniques such as frequency division multiple access (OFDM).IAGW then has the function of part wireless traffic serving GPRS support node (SGSN), and the function of Gateway GPRS Support Node (GGSN) in the original system.

In order to guarantee the smooth evolution of existing UTRAN framework, above-mentioned two-layer node framework has been reused existing protocol to greatest extent.The ERS of wireless interface oral-lateral is owing to merged most of function of former RNC, therefore it has added the function of protocol layers such as media interviews controls (MAC) layers, wireless chain control layer (RLC), PDCP layer and Radio Resource control (RRC) layer again except keeping original physical (L1) function.Then adopt GPRS Tunnel Protocol (GTP)-U between ERS and IAGW.Radio interface protocols stack or perhaps user face protocol stack in the two-layer node framework after the evolution have moved down into ERS, have reduced transmission node, thereby have shortened call setup time-delay and transmission delay, have improved data transmission performance.

Distribute though industry does not propose clear and definite protocol stack at this node architecture at present, proposed the roughly handling process of soft handover.And this soft handover handling process comes with some shortcomings.Such as, for lossless migration, because the air protocol stack moves down into ERS and handles, when the switching flow between generation ERS, source ERS (S-ERS) must send to UE but not obtain the data that UE confirms as yet, and receives but the data that also do not send to UE send to T-ERS from IAGW.And in realizing the process of lossless migration, do not cause data degradation in order to guarantee to switch, S-ERS must carry out stop before switching and UE between transfer of data, thereby caused the time-delay of handoff procedure.

Below in conjunction with Fig. 4 the process of the lossless migration of being initiated by S-ERS is described in detail.

Step 401, S-ERS determine that according to the measurement data of collecting the UE needs switch to T-ERS, send re-positioning request (RELOCATION REQUIRED) message, trigger re-positioning process to IAGW.

Owing to do not have the lur interface between S-ERS and the T-ERS in the framework shown in Figure 3, so can't directly exchange data between S-ERS and the T-ERS, make the direct-cut operation that switches between S-ERS and T-ERS.And S-ERS determines that the lu interface need carry out reorientation in direct-cut operation, therefore sends RELOCATIONREQUIRED message.

After step 402, IAGW receive RELOCATION REQUIRED message, send RELOCATION REQUEST message to T-ERS, request T-ERS is a UE preassignment resource requirement.After step 403, T-ERS receive RELOCATION REQUEST message, start relevant resource allocator, and after necessary resource becomes the distribution of work, send reorientation and confirm (RELOCATION REQUEST ACKNOWLEDGE) message to IAGW, confirm the resource allocation success.

The program that is started comprises: set up RRC connection, RAB carrying, specifically comprise and set up the PDCP/RLC/MAC entity, set up new Radio Link, and start transmission and reception on the new Radio Link; Start the transmission bearer of setting up GTP-U Tunnels for PS RABs simultaneously, set up the user plane bearer between T-ERS and the IAGW.

Step 404, IAGW are after receiving RELOCATION REQUEST ACKNOWLEDGE message, determine that the T-ERS resource allocation is ready, therefore continue the reorientation flow process, send reorientation order (RELOCATION COMMAND) message afterwards, trigger with notice S-ERS and carry out reorientation to S-ERS.

Step 405, S-ERS finish the set-up procedure of reorientation, and carry out following operation after receiving RELOCATION COMMAND message:

Send the STOP order to local RLC, require RLC stop with UE between data exchange; Set up and IAGW between forwarding GTP-U passage, and transmit the data of local cache to T-ERS by this passage and IAGW, promptly sent to UE but do not received the data that UE confirms, and the data that do not send to UE as yet; Obtaining current expectation by primitive from the PDCP layer accepts or PDCP frame number and GTP frame number to be sent, and send forward direction SRNS Serving Radio Network Subsystem context (FORWARD SRNS CONTEXT) message to T-ERS by IAGW, the frame number that is obtained is sent to T-ERS; According to the switching-related parameters in the RELOCATION COMMAND message, generate direct-cut operation message (PHYSICAL CHANNEL RECONFIGURATION), and be sent to UE by the Uu interface, trigger UE and insert Target cell.

After step 406, UE received PHYSICAL CHANNEL RECONFIGURATION message, UE stopped to exchange data with S-ERS, and inserted Target cell according to the information that this message provided; And after successfully inserting Target cell, UE sends direct-cut operation to T-ERS and finishes (PHYSICALCHANNEL RECONFIGURATION COMPLETE) message, carries out the reorientation operation to trigger T-ERS.UE and by reading the T-ERS end PDCP number of frames in the PHYSICAL CHANNEL RECONFIGURATION message obtains the frame number of the up PDCP frame that the current hope of T-ERS accepts.UE obtains behind this frame number by primitive, and the PDCP entity that notice is local is by PDCP entity the reset frame number of the up PDCP frame that current hope sends and the PDCP frame before the deletion.

Step 407, T-ERS begin to carry out the S-ERS function after receiving PHYSICAL CHANNEL RECONFIGURATIONCOMPLETE message; And send RELOCATION DETECT message to IAGW, inform that self having detected SRNS Serving Radio Network Subsystem (SRNS) carries out reorientation.

Afterwards, after IAGW receives this message, user's face is switched to T-ERS by S-ERS.T-ERS obtains the frame number of the descending PDCP frame of the current hope acceptance of UE by reading the UE end PDCP number of frames in the PHYSICAL CHANNEL RECONFIGURATION COMPLETE message.T-ERS obtains behind this frame number by primitive, and the PDCP entity that notice is local by the PDCP entity frame number of the descending PDCP frame that current hope sends of resetting, and is deleted confirmed PDCP frame.After reorientation was finished, data sent from first not confirmed PDCP frame.

Step 408, T-ERS send RELOCATION COMPLETE message to IAGW, and notice IAGW self has finished the RELOCATION process.

IAGW receives RELOCATION COMPLETE message, carries out the lu interface and discharges (Iu release) order, discharges self Iu interface connection to S-ERS.

By above-mentioned handling process, realized harmless switching at framework shown in Figure 3.

By above-mentioned steps 405 as can be known, can not lose for guaranteeing the data in the lossless migration, S-ERS must stop to exchange with the data of UE after receiving RELOCATION COMMAND message.S-ERS also must be with the PDCP data that himself do not send as yet, though or sent but also do not obtained data forwarding that UE confirms to T-ERS, and these data must transmit by IAGW, this will inevitably strengthen time delay for switching, increase network load, and strengthen the complexity of switching flow.

In addition and since the air protocol stack in other words user face protocol stack move down into ERS and handle, and the physical location of ERS has determined the fail safe that it is lower, so the fail safe of user face data can not get ensureing.

The 3GPP network architecture that also has at present another kind of comparatively industry approval, as shown in Figure 5, in this framework E-NodeB and Access GW respectively with framework shown in Figure 3 in ERS and IAGW similar, different is to connect by the Xur interface between the E-NodeB.Do not have clear and definite protocol stack to distribute at this framework yet, but proposed harmless switching flow based on this framework, as shown in Figure 6, the corresponding following steps of this flow process:

Step 601, UE are to source E-NodeB (SNodeB) report measurement information.

Step 602, SNodeB make handover decisions according to metrical information and its other resources, the load condition of UE.

Step 603, SNodeB are transmitted the context information of UE by Xur to TNodeB, such as RB information etc.

Owing to connect by the Xur interface between the E-NodeB, so SNodeB can directly send information to TNodeB.

Step 604, TNodeB are that UE distributes and reserved resource based on the QoS information in the context information of receiving.

Step 605, TNodeB are also returned the response message of receiving context information by Xur to SNodeB.

Step 606, SNodeB begin packing data is sent (packetforwarding) to TNodeB after receiving response message, and stop and UE between data interaction.The data of the TNodeB that sends to comprise: sent to UE but also do not receive the data that UE confirms, and received from Access GW but also be not handed down to the data of UE.

Owing to connect by the Xur interface between the E-NodeB, so SNodeB can adopt the packetforwarding mode to transmit data.

Step 607, SNodeB are the relevant parameter of UE configuration and new sub-district communication, and indication UE switches to new sub-district.

Step 608, UE receive data from Target cell, and synchronous with new sub-district.

Step 609, UE with Target cell synchronously after, send the RB reprovision and finish (RB ReconfigurationComplete) message and give TNodeB, finish to inform to switch.

Step 610, TNodeB are after receiving RB Reconfiguration Complete message, and to AccessGW transmit path handoff request, Access GW then execution route switches.

Step 611, Access GW initiates the resource dispose procedure of Xu interface to S E-NodeB afterwards.

For above-mentioned handoff procedure at framework shown in Figure 5, above-mentioned steps 606 adopts the data transfer mode of dataforwarding, and the handover delay of this mode is bigger, obviously can the serviceability of UE be affected.

This mode also exists SNodeB in the harmless handoff procedure must stop situation with the UE swap data, thereby causes prolonging handover delay, increases network load, increases the problems such as complexity of switching flow.

And there is the unsafe problem of user data equally in this mode.Because NodeB and ERS are in unsafe environment equally, be the data security that guarantees that it transmits, must pay than higher cost, such as, may between adjacent NodeB, set up security association (SA), and data be encrypted, and existing handling process requires can discern mutually between the adjacent NodeB data of being transmitted by NodeB, this requires these NodeB will share same set of key usually, and obviously can there be influence in this to safety of data.Such as, according to above-mentioned switching flow, be easy to infer that data are encryptions of being undertaken by NodeB, and in case break through this NodeB, then can obtain user side data, and if some NodeB be broken, then can know the key of other NodeB.

By above description as can be seen, above-mentioned two kinds of architectural schemes of industry proposition at present all can be regarded as by having the RNC function and adopting the base station of new physical layer technology and the gateway with GGSN and part SGSN function to form, and these two kinds of architectural schemes all exist because of source base station need send the problem that data cause soft switch-over time delay to be grown to target BS, and source base station all needs to stop in advance exchanging with the data of UE.In addition, all there is the safety issue of data and signaling in these two kinds of schemes.

Summary of the invention

In view of this, subject matter to be solved by this invention is to provide a kind of method that realizes that the minizone is switched, and with when realizing that the minizone is switched, reduces handover delay as far as possible, and does not need source base station to stop in advance exchanging with the data of UE.

The present invention also provides a kind of system that realizes that the minizone is switched simultaneously.

For addressing the above problem, the invention provides following technical scheme:

A kind of method that realizes that the minizone is switched of the present invention, be applicable to the 3-G (Generation Three mobile communication system) that comprises base station and gateway with and evolvement network, in base station and gateway chain of command and user face protocol stack are set respectively, this method may further comprise the steps:

A. gateway is treated the data that issue and is carried out buffer memory, and require target BS to carry out resource reservation after receiving handoff request message;

B. target BS carries out resource reservation, and sets up new user's face with gateway;

C.UE obtains the cipher key derivation parameters that described gateway sends by source base station, set up and after resource reservation finishes at new user's face, switch the minizone of finishing UE according to described cipher key derivation parameters, and gateway finishes the path and switch, and data in buffer among the step a is sent to target BS.

Further comprise before the described step a:

A0. source base station switches according to the definite minizone of carrying out of measurement report that UE reports, and the select target base station sends handoff request message to gateway afterwards, and the context context information of UE is sent to gateway by this message;

Among the step a, described gateway requirement target BS carries out resource and is prepared as: gateway issues handoff request message to target BS, and the context information of UE is sent to target BS;

Among the step b, described target BS carries out resource reservation and is: described target BS carries out resource reservation according to the context information of receiving, and returns acknowledge message to gateway.

Among the described step a0, the target BS that described source base station is selected is more than one;

Among the step b, if what target BS returned is not acknowledge message, then gateway is reselected one as the current target base station from other target BS that source base station is selected, and require target BS to carry out resource preparation and follow-up step among the repeated execution of steps a, until the affirmation message of receiving target BS.

Among the described step c, the switching of the minizone of the described UE of finishing comprises:

C1. gateway sends switch acknowledgment message to source base station;

C2. source base station sends switching command to UE;

C3.UE inserts sub-district, target BS place after receiving switching command, send handoff completion message by target BS to gateway afterwards.

UE further comprises before the described step a: when can not satisfy oneself requirement at the down link of determining source base station, break away from the pairing sub-district of source base station, do physical layer synchronization to Target cell, and send the cell association request to the pairing target BS of Target cell; Target BS sends handoff request message to gateway after receiving the cell association request, and the context information of asking this UE;

Among the step a, described gateway further comprises after receiving handoff request message: the request source base station provides the context information of this UE, and after receiving this context information, carries out requiring target BS to carry out the step of resource reservation;

Among the step a, described gateway requirement target BS carries out resource reservation and is: gateway issues handoff request message to target BS, and the context information of UE is sent to target BS;

Among the step c, before switched described minizone of finishing UE, further comprise: UE received the cell association response message that target BS returns after resource reservation is finished.

This method further is arranged on the outer field automatic repeat requests Outer ARQ of user face protocol stack in the gateway;

Among the step a, described gateway is treated the data that issue by OuterARQ and is carried out buffer memory.

Among the described step a, described gateway further descends the signaling Integrity Key when target BS issues handoff request; Described step b further comprises: target BS carries out integrity protection according to this signaling Integrity Key to the signaling of chain of command;

Described step c further comprises: gateway sends to UE with the cipher key derivation parameters that generates by source base station; Among the step c, the minizone of the described UE of finishing is cut and comprised: UE obtains corresponding signaling Integrity Key by this cipher key derivation parameters, and according to this key target BS is sent the chain of command signaling and carry out integrity checking.

Among the step c, the minizone handoff procedure of the described UE of finishing further comprises: UE carries out integrity protection by the signaling Integrity Key that self generates to the chain of command signaling that self sends to target BS; Target BS carries out integrity checking according to the signaling Integrity Key that gateway sends to the chain of command signaling that UE sends.

Described step c further comprises: gateway sends to UE with the cipher key derivation parameters that generates by source base station; Further comprise after the step c: carry out message transmission between target BS and the UE, and described transmission comprises: described UE obtains the cipher key derivation parameters in the switching command, by the corresponding key of this parameter acquiring, according to this key target BS is transmitted the gateway user face data that comes and be decrypted, and self is encrypted by the user face data that target BS is transmitted to gateway according to this key;

Described when new user's face is set up, this method further comprises: gateway is encrypted user side data; UE transmits the gateway user face data that comes according to the described signaling Integrity Key of its acquisition to target BS and is decrypted; Gateway is when receiving the user face data that UE transmits by target BS: gateway is transmitted the user face data that comes to target BS and is decrypted.

Described step c further comprises: gateway sends authentication token by source base station to UE, and described authentication token is generated by gateway, is is perhaps generated and sent to gateway by target ERS;

Among the step c, described UE further comprised before finishing the minizone switching: judge according to the authentication token of receiving whether this target BS is legitimate base station, if then carry out the step that inserts the sub-district; Otherwise refusal inserts the sub-district.

Among the described step a, described gateway when treating the data that issue and carrying out buffer memory, further comprises after receiving handoff request message: the transmission rate that reduces user face data.

This method further comprises: the resource relevant with UE between d. gateway release self and the source base station.

Describedly at base station and gateway the chain of command protocol stack is set respectively and comprises: media control MAC, physical layer PHY, low radio resource control RRC lower, Radio Access Network application protocol expansion RANAP+ and transport network layer TNL are set in the base station; Service Management SM, the high radio resource control RRC higher of grouping mobile management PMM/, RANAP+ and TNL are set in gateway; And the OuterARQ in the chain of command protocol stack is placed in base station or the gateway;

And/or, describedly at base station and gateway user face protocol stack is set respectively and comprises: MAC, PHY, user plane protocol UP and TNL are set in the base station; PDCP, UP, TNL, IP, RTP/TCP/VOIP are set in gateway, and Outer ARQ.

Described base station is wireless station, border ERS, and gateway is IP IAD IAGW; Perhaps the base station is E-base station E-NodeB, and gateway is IAD Access GW.

A kind of system that realizes that the minizone is switched of the present invention comprises base station and gateway in the described system, is respectively equipped with chain of command and user face protocol stack in base station and the gateway, and in the user face protocol stack of gateway, is provided with cache module,

Gateway, be used for after receiving handoff request message, treat the data that issue by cache module and carry out buffer memory, require target BS to carry out resource reservation, and new user's face set up and resource reservation is finished and the minizone of UE switch finish after, execution route switches, and institute's data in buffer is sent to target BS;

Target BS is used for carrying out resource reservation according to the requirement of gateway, and sets up new user's face with gateway;

UE obtains the cipher key derivation parameters that described gateway sends by source base station, is used for setting up and after resource reservation finishes, finishing the minizone and switch at new user's face according to described cipher key derivation parameters.

Described cache module is to be provided with according to the Outer ARQ in the user face protocol stack.

The measurement report that source base station in the described system is used for reporting according to UE is determined to carry out the minizone and is switched, and the select target base station sends handoff request message to gateway.

UE in the described system is further used for breaking away from the pairing sub-district of source base station when the down link of determining source base station can not satisfy oneself requirement, does physical layer synchronization to Target cell, and sends the cell association request to the pairing target BS of Target cell;

Target BS is further used for after receiving the cell association request, sends handoff request message to gateway.

Described gateway further comprises cipher key module, and described cipher key module is used for signaling Integrity Key under target BS, and generates cipher key derivation parameters, and this parameter is sent to UE by source base station;

Target BS is further used for according to the signaling Integrity Key of receiving the signaling of chain of command being carried out integrity protection;

UE is further used for obtaining corresponding signaling Integrity Key according to the cipher key derivation parameters of receiving, and according to this key the chain of command signaling that target BS sends is carried out integrity checking.

Described UE is further used for by the signaling Integrity Key that self generates the chain of command signaling that self sends to target BS being carried out integrity protection;

The signaling Integrity Key that described target BS is further used for sending according to gateway carries out integrity checking to the chain of command signaling that UE sends.

Described gateway further comprises cipher key module, and described cipher key module is used to generate cipher key derivation parameters, and by source base station cipher key derivation parameters is sent to UE; Described UE is further used for obtaining corresponding key according to the cipher key derivation parameters of receiving, according to this key target BS is transmitted the user face data that comes and be decrypted, and self is encrypted by the user face data that target BS is transmitted to gateway according to this key.Described cipher key module is further used for the user face data that sends to UE is encrypted, and the user face data that UE is sent is decrypted.

Described gateway is further used for sending authentication token by source base station to UE, and described authentication token is generated by authentication module, and authentication module is positioned at gateway, perhaps is positioned at target BS, and by target BS authentication token is sent to gateway;

Described UE is further used for confirming according to the authentication token of receiving whether this target BS is legitimate base station before finishing the minizone switching.

The present invention program is at two kinds of framework modes and the similar framework mode thereof mentioned in the background technology, by chain of command and user face protocol stack being set respectively in base station and gateway, and the Outer ARQ of user face protocol stack is arranged in the gateway, and make gateway after receiving handoff request message, treat the data that issue by this OuterARQ and carry out buffer memory, make the present invention to realize guaranteeing that family face data can not lose, thereby also do not need source base station to stop in advance having transmitted data by the retransmission mechanism of Outer ARQ.

The present invention is provided with the signaling Integrity Key by gateway, and cipher key derivation parameters is set, and obtains the signaling Integrity Key by UE according to cipher key derivation parameters, has both guaranteed the safety of key, has guaranteed the integrality of signaling again.

Similarly, the user face data key is set, cipher key derivation parameters is set, and obtains key according to cipher key derivation parameters, thereby both guaranteed the fail safe of user face data key, guaranteed the safety of user face data again by UE by gateway.

The present invention program can also make the user can judge whether target BS is the legitimate base station of this UE approval by this authentication token, thereby avoid the user to enter insecure sub-district by generating authentication token and send to UE at target BS.

The present invention also provides common switching flow of being initiated by source base station and the forward direction switching flow of being initiated by UE.

Description of drawings

Fig. 1 is present UMTS system construction drawing;

Fig. 2 be RNS among the present UTRAN structure and with the annexation schematic diagram of CN;

Fig. 3 is present two-layer node architectural configurations figure;

Fig. 4 is present switching flow figure at framework shown in Figure 3;

Fig. 5 is the structure chart of the another kind of evolution architecture of present 3GPP;

Fig. 6 is present switching flow figure at framework shown in Figure 5;

Fig. 7 is the schematic diagram of chain of command set in the embodiment of the invention;

Fig. 8 is the schematic diagram of user's face set in the embodiment of the invention;

Fig. 9 is the present invention program's switching flow figure;

Figure 10 is the message flow sequential chart of the present invention program at common switching flow;

Figure 11 is the message flow sequential chart of the present invention program at the forward direction switching flow

Figure 12 is the present invention program's a system construction drawing.

Embodiment

At first need to prove, the present invention is referred to as the base station with ERS and the E-NodeB in two kinds of frameworks mentioning in the background technology, IAGW and Access GW is referred to as gateway, as stated in the Background Art, the base station has the RNC function, and gateway has GGSN and part SGSN function.Certainly, the present invention program is also applicable to other similar frameworks.

The present invention program is respectively equipped with chain of command and user face protocol stack in base station and gateway, and is provided with cache module in the user face protocol stack of gateway, is provided with based on this, and the present invention program's Organization Chart as shown in figure 12.

Based on above-mentioned setting, gateway then is used for after receiving handoff request message, treat the data that issue by cache module and carry out buffer memory, require target BS to carry out resource reservation, and new user's face set up and resource reservation is finished and the minizone of UE switch finish after, execution route switches, and institute's data in buffer is sent to target BS;

UE is used for setting up and after resource reservation finishes, finishing the minizone and switch at new user's face.

Specifically, the present invention program is at two kinds that mention in the background technology concrete framework modes, mainly be by chain of command and user face protocol stack being set respectively in base station and gateway, by gateway data are carried out buffer memory, and propose corresponding switching flow, thereby realize smoothly in the minizone, switch apace based on this protocol stack.

And when realizing the buffer memory of gateway, can realize that wherein, functions of retransmission has multiple specific implementation automatically, is example with outer field automatic repeat requests (Outer ARQ) only here by automatic functions of retransmission being arranged in the gateway at user face protocol stack.Outer ARQ also is called upper strata (Upper) ARQ.Therefore, above-mentioned cache module also can be to be provided with according to Outer ARQ.

Reach specific embodiment below more in conjunction with the accompanying drawings the present invention program is done further detailed description.

The present invention program can be provided with the chain of command protocol stack as required.Such as, MAC, PHY, low Radio Resource control (RRC (lower)), the expansion of RAN application protocol (RANAP+) and transport network layer (TNL) can be set in the base station; SM, grouping mobile management (PMM)/RRC (higher), RANAP+ and TNL are set in gateway.Wherein, RRC (lower) is responsible for mainly that RRC establishment of connection, UE are measured control and to the measurement control of MAC/PHY etc. and the closer function of idle wireless resource management, RRC (higher) then lays particular emphasis on the interactive function with the NAS layer more.Outer ARQ in the chain of command protocol stack then both can be placed in the base station, also can be placed in the gateway, and if be placed in the base station, can also accelerate the transmission rate of space interface signaling.

For user face protocol stack, can be provided with as required equally.Such as, MAC, PHY, user plane protocol (UP, U-plane Protocol) and TNL can be set in the base station; PDCP, UP, TNL, IP are set in gateway, RTP/TCP/VOIP can also further be set, but in gateway, Outer ARQ must be set.In addition, user's face Outer ARQ can be set simultaneously also in the base station, the Outer ARQ in the base station is mainly used in non-switching occasion.At this situation, when needs were carried out the minizone switching, source base station also needed the information that comprises that some are extra when sending the context information of UE, such as the sequence number of the data that issue of not having enough time among the Outer ARQ of source base station, and the sequence number etc. that has obtained the data that UE confirms.Outer ARQ in the gateway then deletes the data that UE has received in the information of self buffer memory according to these information, and issues to target BS and not obtain the data that UE confirms.

Fig. 7 and Fig. 8 are respectively the specific embodiment that chain of command and user's face are set among the present invention program.

The present invention program's overall process flow as shown in Figure 9, corresponding following steps:

Step 901, gateway begin to treat the data that issue and do buffer memory after receiving handoff request message, and require target BS to carry out the resource preparation;

Step 902, target BS are set up new user's face with gateway after resource is ready to complete;

Step 903, after new user's face is set up, switch the minizone of finishing UE, and the gateway execution route switches, and data in buffer is sent to target BS.

Afterwards, target BS can carry out message transmission with UE.

Certainly, be the integrality of assurance chain of command signaling, and the fail safe of user face data, corresponding key can also be set.

In addition, in above-mentioned handling process, the switching of UE can be proposed according to the measurement report that UE reports by the base station, what promptly carry out is common switching flow, also can initiatively be proposed by UE, what promptly carry out is the forward direction switching flow, that is to say, the handoff request message that gateway is received may be that source base station is unasked, also may be that target BS proposes after the cell association request of receiving UE.

Therefore be described in detail at both of these case more respectively below.And the plan of establishment to key is described in both of these case.

Since identical at the hand-off process flow process of Fig. 3 and framework shown in Figure 5, be example only below therefore with framework shown in Figure 3, above-mentioned two kinds of switching flows are described respectively.

Under framework shown in Figure 3, the message flow sequential of the common switching flow that is proposed by the base station as shown in figure 10.At this handling process, the measurement report that needs the S-ERS in the system to report according to UE is determined to carry out the minizone and is switched, and selects T-ERS, and sends handoff request message to gateway.

The corresponding following steps of this switching flow:

Step 1001, UE reporting measurement reports are given S-ERS.

Step 1002, S-ERS determine to initiate the minizone according to the measurement report of receiving and switch.

Step 1003, S-ERS select T-ERS, send the handoff request message that the sub-district switches to T-ERS to IAGW afterwards, and the context information of UE is uploaded to IAGW by this message.

The context information spinner that is sent will comprise Signaling Radio Bearer (SRB) information.

S-ERS can also select a plurality of T-ERS, and the relevant information of these T-ERS is sent to IAGW, selects a suitable T-ERS for IAGW.

Step 1004, IAGW treat the data of sending out and do buffer memory after receiving handoff request.

Institute's data in buffer sends to corresponding T-ERS after need waiting until and switching again.And IAGW can also further reduce the transmission rate of user face data, needs the data in buffer amount with minimizing.

In addition, because S-ERS does not know the cell information of other ERS, and IAGW knows, so IAGW can play the effect of switching coordination, in case find the local resource anxiety of the T-ERS of current selected, IAGW can select other T-ERS from the T-ERS information that S-ERS sends.Certainly, if any one T-ERS can't offer UE, then IAGW can return the information of a handoff failure to S-ERS.

Step 1005, IAGW issue handoff request to T-ERS, and the context information of receiving is sent to T-ERS.

Step 1006, T-ERS are receiving handoff request, and make the whether judgement of access according to the situation of self, and carry out resource reservation according to the context information of receiving for this UE under the situation of access.

Step 1007, T-ERS set up new user's face with IAGW after resource reservation is finished, send the affirmation message that resource reservation is finished to IAGW simultaneously.

Certainly, this message can be included in the message that user's face set up.

Step 1008, IAGW send switch acknowledgment message to S-ERS after receiving the affirmation message that T-ERS sends.

Step 1009, S-ERS send switching command to UE after receiving switch acknowledgment message.

Step 1010, UE separate with the cell-of-origin after receiving switching command, and insert Target cell.

Step 1011, UE send handoff completion message to T-ERS after inserting Target cell, T-ERS then sends this handoff completion message to IAGW.

Step 1012～1013, IAGW are after receiving the handoff completion message of UE, and execution route switches, and will before data in buffer send to T-ERS, discharge again afterwards self with S-ERS between the resource relevant with UE.

In addition, the step that execution route switches in the step 1012 also can be done certain time after step 1008, before step 1011.For real time business, can issue data so in advance and reduce service outage duration, and professional for can't harm, because the assurance of Outer ARQ is arranged, therefore execution route switching in advance also is feasible.

In above-mentioned common switching flow,, can also carry out some settings of maintaining secrecy for further guaranteeing the fail safe of data and signaling.

Such as, can be in above-mentioned steps 1005, IAGW is when T-ERS issues handoff request, can be simultaneously to T-ERS command transmitting Integrity Key, can to be IAGW produce by calculating according to subscriber identity information and T-ERS information this key, be used to eat dishes without rice or wine or UE and IAGW between the signaling integrity protection; In above-mentioned steps 1006 or 1007, T-ERS then can carry out integrity protection to the signaling in the chain of command according to this signaling Integrity Key, promptly increases this signaling Integrity Key in signaling.Correspondingly, in above-mentioned steps 1008, IAGW can carry cipher key derivation parameters in the switch acknowledgment message that S-ERS sends, so that UE can go out the signaling Integrity Key of chain of command by cipher key derivation parameters and the information inferences such as identify label of self, thereby can obtain the signaling of chain of command safely, exactly, thereby and can realize authentication between UE and the T-ERS.

Specifically, carry out in the process of switching the minizone at UE, UE can carry out integrity checking to the chain of command signaling that T-ERS sends after obtaining the signaling Integrity Key, so-called integrity checking is judges whether the key that carries in the chain of command signaling is identical with the signaling Integrity Key of self, if it is identical, confirm that then this signaling was not modified, otherwise, think that signaling was modified, and abandon this signaling, thereby realize that UE authenticates T-ERS according to this signaling Integrity Key.

At above-mentioned disposition, cipher key module need further be set in gateway, this cipher key module is used for signaling Integrity Key under T-ERS, and generates cipher key derivation parameters, and this parameter is sent to UE by S-ERS; T-ERS then carries out integrity protection according to the signaling Integrity Key of receiving to the signaling of chain of command; UE then obtains corresponding signaling Integrity Key according to the cipher key derivation parameters of receiving, and according to this key the chain of command signaling that T-ERS sends is carried out integrity checking.

Similarly, T-ERS also can authenticate UE according to this signaling Integrity Key.Specifically, IAGW can send to T-ERS with the signaling Integrity Key earlier, and in carrying out the process of switching the minizone, UE then can carry out integrity protection to the chain of command signaling that self sends to T-ERS; T-ERS carries out integrity checking according to the signaling Integrity Key of receiving to the chain of command signaling that UE sends, if inspection is passed through, thinks that then this UE has passed through authentication.

IAGW can also be set the user face data that it sent is encrypted, to guarantee the fail safe of user face data.Specifically, can encrypt user face data IAGW, IAGW sends cipher key derivation parameters to S-ERS in above-mentioned steps 1008 then, S-ERS then sends to UE with this cipher key derivation parameters, UE calculates corresponding key according to this cipher key derivation parameters again, according to this key IAGW is decrypted by the user face data that T-ERS sends afterwards, and the user face data that sends to IAGW by T-ERS is encrypted; Correspondingly, IAGW then can be decrypted the user face data that the target BS forwarding comes.

Handle at above-mentioned encryption and decryption user face data, also cipher key module need be set in gateway, this cipher key module can be same module with the cipher key module of above-mentioned setting, can certainly establish a module in addition, this cipher key module is encrypted the user face data that sends to UE, the user face data that UE is sent is decrypted, and generates cipher key derivation parameters, and by S-ERS cipher key derivation parameters is sent to UE; UE then obtains corresponding key according to the cipher key derivation parameters of receiving, according to this key T-ERS is transmitted the user face data that comes and is decrypted, and according to this key self is encrypted by the user face data that T-ERS is transmitted to gateway.

For another example, in above-mentioned steps 1007, T-ERS is when IAGW sends acknowledge message, can return an authentication token simultaneously, be used for UE when switching to self networking that provides, being the authentication of T-ERS, also is whether be legal ERS in expectation to UE if can determine to be about to switch the target ERS that goes according to this authentication token.Certainly, this token also can be generated by IAGW.In this case, can be set to be generated by authentication module by authentication token, authentication module can be positioned at gateway; Also can be positioned at target BS, and authentication token be sent to gateway by target BS.

Correspondingly, in above-mentioned steps 1009, S-ERS should comprise authentication token in the switching command that UE sends, and whether UE then can come the identity of authenticating network correct according to this token, is switched among the T-ERS of forgery preventing.

More than common switching flow is described in detail, below again under the framework shown in Figure 3, the forward direction switching flow that is proposed by UE is described, its pairing message flow sequential as shown in figure 11.At this handling process, need the UE in the system to be further used for when the down link of determining source base station can not satisfy oneself requirement, break away from the pairing sub-district of source base station, do physical layer synchronization to Target cell, and send the cell association request to the pairing target BS of Target cell; Target BS then after receiving the cell association request, sends handoff request message to gateway.

The corresponding following steps of this switching flow:

The condition of acceptance of UE is bad on step 1101, the S-ERS down link.

Step 1102, UE break away from the cell-of-origin, and it is synchronous to be L1 to new sub-district.

Step 1103, UE send the cell association request to T-ERS.

This request is similar to current cell update request.

Step 1104, T-ERS ask for the context information of this UE to IAGW after receiving the cell association request that UE sends.

Step 1105, IAGW after the context transmission request of receiving T-ERS, the data that buffer memory is to be issued.

And IAGW can also further reduce the transmission rate of user face data, needs the data in buffer amount with minimizing.

Step 1106, IAGW send context transmission request to S-ERS, to obtain the part context information of UE, if this information spinner SRB information.

Step 1107, S-ERS send to IAGW with relevant context information after receiving transfer request message.

Step 1108, IAGW are transmitted to T-ERS with this information after receiving context information.

Step 1109, T-ERS do access and judge, and carry out resource reservation after receiving context information.

Step 1110, T-ERS and after resource reservation is finished send the cell association response message to UE, and the new user's face between foundation and the IAGW.

Step 1111, IAGW carry out the path and switch, and data in buffer in the step 1105 is issued to T-ERS after definite T-ERS resource reservation is finished.

Step 1112, UE carry out the minizone and switch, and return handoff completion message to T-ERS after receiving the cell association response that T-ERS sends, and T-ERS gives IAGW with this forwards again after receiving this handoff completion message.

Step 1113, IAGW discharge the resource relevant with UE between self and the S-ERS after receiving the handoff completion message of UE.

Promptly realized the forward direction switching by above-mentioned steps.

In above-mentioned forward direction switching flow, can increase cipher key function equally, such as, it is that user face data increases key that IAGW is set.IAGW can also be provided with the integrity protection key for the signaling of chain of command.IAGW can also further be provided with corresponding derivation parameter equally, and UE then can carry out corresponding calculated according to this parameter of deriving, thereby obtains corresponding key, and specifically encryption and decrypting process are identical with the processing at flow process shown in Figure 10 for it, so repeat no more.

Certainly; for above-mentioned two kinds of switching flows; it is identical that all user's face keys can be set; in this case; for guaranteeing user's face key and the fail safe of integrity protection key on each ERS; by at the different derivation parameter of each ERS configuration, thereby even make user's face key of an ERS be cracked, user face data under other ERS and integrity protection key be safety still.This processing mode need IAGW in step 1108 when T-ERS returns context information, generate new derivation parameter and send to T-ERS.Should the derivation parameter send to UE by T-ERS more afterwards by the cell association response message.

The above only is the present invention program's preferred embodiment, not in order to limit protection scope of the present invention.

Claims

1, a kind of method that realizes that the minizone is switched, be applicable to the 3-G (Generation Three mobile communication system) that comprises base station and gateway with and evolvement network, it is characterized in that in base station and gateway chain of command and user face protocol stack are set respectively, this method may further comprise the steps:

C.UE obtains the cipher key derivation parameters that described gateway sends by source base station, set up and after resource reservation finishes at new user's face, switch the minizone of finishing UE according to described cipher key derivation parameters, and the switching of gateway execution route, and data in buffer among the step a is sent to target BS.

2, method according to claim 1 is characterized in that, further comprises before the described step a:

3, method according to claim 2 is characterized in that among the described step a0, and the target BS that described source base station is selected is more than one;

4, method according to claim 1 is characterized in that among the described step c, and the switching of the minizone of the described UE of finishing comprises:

C1. gateway sends switch acknowledgment message to source base station;

C2. source base station sends switching command to UE;

5, method according to claim 1, it is characterized in that, UE further comprises before the described step a: when can not satisfy oneself requirement at the down link of determining source base station, break away from the pairing sub-district of source base station, do physical layer synchronization to Target cell, and send the cell association request to the pairing target BS of Target cell; Target BS sends handoff request message to gateway after receiving the cell association request, and the context information of asking this UE;

According to any described method in the claim 1 to 5, it is characterized in that 6, this method further is arranged on the outer field automatic repeat requests Outer ARQ of user face protocol stack in the gateway;

Among the step a, described gateway is treated the data that issue by Outer ARQ and is carried out buffer memory.

7, according to any described method in the claim 1 to 5, it is characterized in that among the described step a that described gateway further descends the signaling Integrity Key when target BS issues handoff request;

Described step b further comprises: target BS carries out integrity protection according to this key to the signaling of chain of command;

Described step c further comprises: gateway sends to UE with the cipher key derivation parameters that generates by source base station;

Among the described step c, the switching of the minizone of the described UE of finishing comprises: UE obtains corresponding signaling Integrity Key by described cipher key derivation parameters, and according to this signaling Integrity Key the chain of command signaling that target BS sends is carried out integrity checking.

8, method according to claim 7, it is characterized in that among the described step c that the minizone handoff procedure of the described UE of finishing further comprises: UE carries out integrity protection by the signaling Integrity Key that self generates to the chain of command signaling that self sends to target BS; Target BS carries out integrity checking according to the signaling Integrity Key that gateway sends to the chain of command signaling that UE sends.

9, according to any described method in the claim 1 to 5, it is characterized in that,

Further comprise after the described step c: carry out message transmission between target BS and the UE, and described transmission comprises: described UE obtains the cipher key derivation parameters in the switching command, by the corresponding signaling Integrity Key of this parameter acquiring, and self is encrypted by the user face data that target BS is transmitted to gateway according to this signaling Integrity Key.

10. method according to claim 9 is characterized in that, and is described when new user's face is set up, and also comprises:

Gateway is encrypted user side data;

UE transmits the gateway user face data that comes according to its described signaling Integrity Key that obtains to target BS and is decrypted;

Gateway is transmitted the user face data that comes to target BS and is decrypted when receiving the user face data that UE transmits by target BS.

11, according to any described method in the claim 1 to 5, it is characterized in that described step c further comprises: gateway sends authentication token by source base station to UE, described authentication token is generated by gateway, is is perhaps generated and sent to gateway by target BS;

12, method according to claim 1 is characterized in that among the described step a, and described gateway when treating the data that issue and carrying out buffer memory, further comprises after receiving handoff request message: the transmission rate that reduces user face data.

13, method according to claim 1, it is characterized in that, describedly at base station and gateway the chain of command protocol stack is set respectively and comprises: media control MAC, physical layer PHY, low radio resource control RRC lower, Radio Access Network application protocol expansion RANAP+ and transport network layer TNL are set in the base station; Service Management SM, the high radio resource control RRC higher of grouping mobile management PMM/, RANAP+ and TNL are set in gateway; And the Outer ARQ in the chain of command protocol stack is placed in base station or the gateway;

And/or, describedly at base station and gateway user face protocol stack is set respectively and comprises: MAC, PHY, user plane protocol UP and TNL are set in the base station, or Outer ARQ further is set; PDCP, UP, TNL, IP, RTP/TCP/VOIP are set in gateway, and Outer ARQ.

14, method according to claim 1 is characterized in that, described base station is wireless station, border ERS, and gateway is IP IAD IAGW; Perhaps the base station is E-base station E-NodeB, and gateway is IAD Access GW.

15, a kind of system that realizes that the minizone is switched comprises base station and gateway in the described system, it is characterized in that, be respectively equipped with chain of command and user face protocol stack in base station and the gateway, and in gateway, be provided with cache module,

16, system according to claim 15 is characterized in that, described cache module is to be provided with according to the Outer ARQ in the user face protocol stack.

17, system according to claim 15 is characterized in that, the measurement report that the source base station in the described system is used for reporting according to UE is determined to carry out the minizone and switched, and the select target base station sends handoff request message to gateway.

18, system according to claim 15, it is characterized in that, UE in the described system is further used for when the down link of determining source base station can not satisfy oneself requirement, break away from the pairing sub-district of source base station, do physical layer synchronization to Target cell, and send the cell association request to the pairing target BS of Target cell;

19, system according to claim 15, it is characterized in that described gateway further comprises cipher key module, described cipher key module is used for signaling Integrity Key under target BS, and the generation cipher key derivation parameters, and this parameter sent to UE by source base station;

20, system according to claim 19 is characterized in that, described UE is further used for by the signaling Integrity Key that self generates the chain of command signaling that self sends to target BS being carried out integrity protection;

21, system according to claim 15 is characterized in that, described gateway further comprises cipher key module, and described cipher key module is used to generate cipher key derivation parameters, and by source base station cipher key derivation parameters is sent to UE;

Described UE is further used for obtaining corresponding key according to the cipher key derivation parameters of receiving, according to this key target BS is transmitted the user face data that comes and be decrypted, and self is encrypted by the user face data that target BS is transmitted to gateway according to this key.

22, system according to claim 21 is characterized in that, described cipher key module is further used for the user face data that sends to UE is encrypted, and the user face data that UE is sent is decrypted.

23, system according to claim 15, it is characterized in that, described gateway is further used for sending authentication token by source base station to UE, described authentication token is generated by authentication module, and authentication module is positioned at gateway, perhaps be positioned at target BS, and authentication token sent to gateway by target BS;

24, a kind of method that realizes that the minizone is switched, be applicable to the 3-G (Generation Three mobile communication system) that comprises base station and gateway with and evolvement network, it is characterized in that this method may further comprise the steps:

A. gateway requires target BS to carry out resource reservation after receiving handoff request message;

B. target BS carries out resource reservation;

C.UE obtains the cipher key derivation parameters that described gateway sends by source base station, and after resource reservation was finished, switched the minizone of finishing UE according to described cipher key derivation parameters.

25, method according to claim 24, it is characterized in that, among the step c, the minizone switching of the described UE of finishing comprises: UE obtains corresponding signaling Integrity Key by described cipher key derivation parameters, and according to this signaling Integrity Key the chain of command signaling that target BS sends is carried out integrity checking.

26, method according to claim 25 is characterized in that among the described step c, and the minizone handoff procedure of the described UE of finishing further comprises:

UE carries out integrity protection by the signaling Integrity Key that self generates to the chain of command signaling that self sends to target BS;

Target BS carries out integrity checking according to the signaling Integrity Key that gateway sends to the chain of command signaling that UE sends.

27, according to any described method in the claim 24 to 26, it is characterized in that,

Further comprise after the step c: carry out message transmission between target BS and the UE, and described transmission comprises: described UE obtains corresponding signaling Integrity Key by described cipher key derivation parameters, and according to this signaling Integrity Key self is encrypted by the user face data that target BS is transmitted to gateway.

28. method according to claim 27 is characterized in that, also comprises:

Gateway is encrypted user side data;

UE transmits the gateway user face data that comes according to the described signaling Integrity Key of its acquisition to target BS and is decrypted;