CN111200812B

CN111200812B - Method for accelerating NFs mutual discovery in 5G core network

Info

Publication number: CN111200812B
Application number: CN202010014267.1A
Authority: CN
Inventors: 邱权冠; 吕东; 苏国章
Original assignee: Guangzhou Aipu Road Network Technology Co Ltd
Current assignee: Guangzhou Aipu Road Network Technology Co Ltd
Priority date: 2020-01-07
Filing date: 2020-01-07
Publication date: 2021-07-20
Anticipated expiration: 2040-01-07
Also published as: CN111200812A

Abstract

The invention provides a method for accelerating NFs mutual discovery in a 5G core network, which adopts reference factors of a NFs local cache NRF discovery result and a mode of mapping the position and state information of an opposite end NF by using a cache mapping table, avoids NFs repeated NRF query, improves NFs mutual discovery efficiency, and provides a mode of dynamically modifying a configuration file on NFs according to network deployment requirements, so that a network administrator can change the reference factors of a certain NF cache with minimum cost.

Description

Method for accelerating NFs mutual discovery in 5G core network

Technical Field

The invention relates to the technical field of mobile communication, in particular to a method for accelerating NFs mutual discovery in a 5G core network.

Background

In a service-based architecture SBA of a 5G core network (abbreviated as 5GC), network element functions are subdivided, more network functional entities NFs are evolved, and the NFs need to be subjected to mutual discovery and selection processes firstly if the NFs need to communicate with each other. The methods for NFs to discover each other are defined in versions R15 and R16 of the 3GPP protocol TS23501-g30, namely, local acquisition and NRF discovery. In the two discovery modes, local acquisition usually adopts a mode of writing a static configuration file into NF address information of an opposite terminal. If the NRF discovery mode is adopted, different reference Factors (such as DNN, S-NSSAI, etc.) need to be adopted according to different NF types through NRF discovery, which may cause that the reference Factors discovered each time are the same, the same NF is repeatedly accessed for many times, resulting in network resource waste and network efficiency reduction. Table one lists some optional Factors corresponding to NF found in TS23501-g30 protocol (the specific Factors use is determined by operator policy and network deployment).

AMF	SMF	AUSF	UPF
				S-NSSAI	DNN	PLMN	DNN
AMF Region ID	S-NSSAI	Routing Indicator	S-NSSAI
				AMF Set ID	NSI-ID	Group ID	SSC mode
PLMN	Access Type	SUPI	PDU Session Type

TABLE 1

In various related patent schemes related to NFs mutual discovery content of 5GC networks, for example, "method, device and readable storage medium for NF discovery through NRF" of chinese patent application publication No. CN109803242A, "network function NF management method and NF management device" of chinese patent application publication No. CN109417492A, "method and device for discovering network function service" of chinese patent application publication No. CN109391592A, all have no content for accelerating NFs mutual discovery.

NFs mutual discovery mode, the 3GPP protocol gives two modes (local acquisition and NRF discovery) and NFs mutually selected Factors, which are actually used depending on the network needs. The local acquisition adopts a static configuration file mode, the network flexibility is poor, the configuration file needs to be changed once other NFs location information is changed, and the location information of roaming NFs cannot be acquired. While the NRF discovery mode may cause repeated access (for example, the AMF discovers the same SMF multiple times), which results in network resource waste and network efficiency reduction, NFs may cache the NRF query result for the next discovery, so far, there is no public caching method and algorithm. Even though NFs caches NRF discovery results locally, there is no corresponding factor corresponding to the discovery results, and the network administrator cannot configure the cached factor type in NFs, once the network deployment changes, the Factors cannot be dynamically adjusted, the network mode will be rigid, and the discovery policy and NFs processing efficiency cannot be optimized.

Disclosure of Invention

In view of the above, to solve the problems in the prior art, the present invention is to accelerate NFs mutual discovery process, mainly to solve the problem that when NFs mutual discovery occurs, the network communication efficiency is reduced due to repeated access to NRF. Meanwhile, the invention improves the flexibility of NFs in mutual discovery.

The purpose of the invention is realized by the following technical scheme:

the invention provides a method for accelerating NFs mutual discovery in a 5G core network, which comprises the following steps:

step S1, when the NF needs to communicate with the opposite end NF, the NF decodes the message triggering the communication process to obtain data or obtains the type and reference factor of the opposite end NF from the NF stored data;

step S2, the NF obtains the type of the opposite terminal NF generated by the strategy configuration file configured by the network administrator and the key value template generated in the initialization stage from the self cache;

step S3, judging whether the type of the NF of the opposite terminal exists in the self cache of the step S2, if so, combining the corresponding key value template and the reference factor in the self cache to generate the key value of the cache mapping table, and turning to the step S4; otherwise go to step S5;

step S4, judging whether the key value has a mapping value in the cache mapping table, if yes, directly obtaining the mapping value to communicate with an opposite terminal NF, otherwise, turning to step S5;

and step S5, the NF sends an opposite end NF discovery request to the NRF, the NRF returns the position and state information of the opposite end NF according to the NF request, and the NRF returns the result to directly communicate with the opposite end NF.

Further, step S5 includes a step of updating the cache mapping table according to the result returned by the NRF.

Further, the step of updating the cache mapping table is as follows: when the NF receives the information of the NF position and the state of the opposite terminal returned by the NRF, the NF firstly decodes the information, then generates a key value according to the decoded reference factor and the key value template in the cache, and updates the generated key value into a cache mapping table.

Further, the step of generating the key-value template in the initialization stage includes:

step S201, reading each caching strategy configured by a network administrator from a strategy configuration file, wherein each caching strategy comprises the type of each NF and a corresponding reference factor;

step S202, generating a policy table in a cache;

and step S203, generating a key value template in the cache according to the NFs types in the policy table and the corresponding reference factors.

Further, the generating a key value of the cache mapping table includes:

in the process of generating the key value template, the reference factors are substituted for the placeholders through the programming language interface, and the unique key value in the cache mapping table is generated.

Further, the mapping value is an IP address of the NF of the opposite end or a fully qualified domain name.

The invention has the beneficial effects that:

1. by using NFs local cache hash address mapping table, the efficiency of NFs mutual discovery is improved, and the decrease of network speed caused by repeated access to NRF is avoided.

2. NFs, the reference factors and the address information of the opposite terminal NFs are mutually found to construct a hash address mapping table, and the corresponding relation between the reference factors and the address information of the opposite terminal NFs is effectively managed.

3. Algorithms such as a generated key value template and a Hash mapping table are used, and the processing efficiency and light weight of the local cache program are guaranteed. The unique key value generated according to the reference factors is stored in the hash address mapping table, so that the stored content is effectively managed, and a large number of reference factors are not stored.

4. Providing a configuration file that allows a network administrator to select local cache NF types and reference factors allows the network administrator to optimize NFs the mutual discovery efficiency.

Drawings

FIG. 1 is a flow chart of NFs discovery with each other in an accelerated 5G core network according to the present invention;

FIG. 2 is a flowchart illustrating the generation of cache mapping table key values Kp (m) according to the present invention;

FIG. 3 is a diagram of a cache address hash mapping table;

FIG. 4 is a flow chart of updating a cache address hash mapping table;

FIG. 5 a network topology diagram for multiple UEs and SMFs;

fig. 6 is a communication flow diagram of multiple UEs and multiple SMF scenarios according to a first embodiment;

fig. 7 is a flowchart of updating a cache address hash mapping table by multiple UEs and multiple SMFs according to the first embodiment.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

The embodiments of the present disclosure are described below with specific examples, and other advantages and effects of the present disclosure will be readily apparent to those skilled in the art from the disclosure in the specification. It is to be understood that the described embodiments are merely illustrative of some, and not restrictive, of the embodiments of the disclosure. The disclosure may be embodied or carried out in various other specific embodiments, and various modifications and changes may be made in the details within the description without departing from the spirit of the disclosure. It is to be noted that the features in the following embodiments and examples may be combined with each other without conflict. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.

Example one

The invention adopts NFs Factors of local cache NRF (network resource management function entity) discovery result and uses Hash address mapping table (also called cache mapping table) H_(addr)The way of Table mapping NFs address information of opposite end avoids NFs repeated query of NRF, improves NFs efficiency of mutual discovery, and provides a way of dynamically modifying NFs configuration files according to network deployment needs, so that a network administrator can change the Factors of a certain NF cache with minimum cost.

The method for accelerating NFs mutual discovery in a 5G core network, as shown in FIG. 1, comprises the following steps:

and step S1, when the NF needs to communicate with the opposite end NF, the NF decodes the message triggering the communication process into data or obtains the type of the opposite end NF and the reference Factors factor from the NF storage data.

Step S2, the NF obtains the type of the opposite terminal NF generated by the strategy configuration file configured by the network administrator from the self cache and the key value template K generated in the initialization stage_tmpl(m)；

The key value template K in the initialization phase is described in detail with reference to FIG. 2_tmplThe generation method of (m) specifically comprises the following steps:

step S201, slave policy configuration file P_NFReading each caching strategy P configured by network administrator in Doc_NF(m) each caching strategy comprises the type of each NF and corresponding reference Factors;

step S202, generating a policy table P in the cache_NFTable；

Step S203, according to the policy table P_NFNFs types in Table and corresponding reference Factors factor, generating key-value template K in cache_tmpl(m)。

Although the efficiency of character recognition and processing in this process is not high, the number of strategies generally configured is small (NFs types are not many), and the generation of the key-value template K is realized_tmpl(m) ofThe process only occurs at initialization and is not repeated subsequently.

Step S3, judging whether the type of the NF of the opposite terminal exists in the self cache of the step S2, if so, setting the corresponding key value template K in the self cache_tmpl(m) combining the reference Factors into a key value Kp (m) of the cache mapping table, and turning to the step S4; otherwise go to step S5.

In the generation of K_tmplIn the process of (m), the reference Factors factor are substituted for the placeholder through a programming language interface, and a cache mapping table H is generated_(addr)Unique key value Kp (m) in Table.

At K_tmplIn (m) "% s" represents character string placeholder, in generating K_tmpl(m) replacing the placeholders with Factors through the programming language interface to generate a cache mapping table H_(addr)Unique key value Kp (m) in Table. If a factor value is null, a null value of "null" is assigned. In policy profile P_NFIn Doc, the caching policy P_NF(m) specifies the NF type put into cache and the generated key-value template K_tmpl(m) the format of P can be dynamically changed according to the optimization strategy of the network administrator_NFAnd (4) Doc. The purpose of adopting the algorithm is to simplify the processing process, to use the language with high efficiency, and to enable the network administrator to optimize the cache acceleration strategy according to the network requirement.

Step S4, determining the key value Kp (m) in the cache mapping table H_(addr)If the Table has a mapping value, if the key value Kp (m) is in the cache mapping Table H_(addr)If the Table has the mapping value, the mapping value is directly obtained to communicate with the opposite end NF, otherwise, the step S5 is performed.

The mapping value is the IP address or the Fully Qualified Domain Name (FQDN) of the NF at the opposite end. After obtaining Kp (m), H is entered_(addr)Table finds the IP address or fully qualified domain name of peer NFs. FIG. 3 is a cache mapping table H_(addr)Table, one Kp (m) in the cache mapping Table uniquely corresponds to the IP address or Fully Qualified Domain Name (FQDN) of one NF if Kp (m) is in H_(addr)If the Table has a mapping value, the mapping value can be directly used for communicating with the NF of the opposite end, and the NRF discovery process is skipped. If Kp(m) there is no mapping value, a request is issued to the NRF to discover the peer NF.

Preferably, after step S5, the method further includes a step of updating the cache mapping table according to a result returned by the NRF, as shown in fig. 4, specifically:

when the NF receives the information of the NF position and the state of the opposite end returned by the NRF, the NF firstly decodes the information, and then the NF decodes the information according to the decoded reference Factors and the key value template K in the cache_tmpl(m) generating key value Kp (m), and updating cache mapping table H_(addr)Table。

The application scenario of the method of the present invention is shown below using one multi-UE and multi-SMF scenario as an example.

Fig. 5 is a network topology diagram of the present example, in which some NFs not used in the example have been omitted from the diagram.

Fig. 6 is a network communication flow diagram of the present example, and in fig. 6, two UEs (UE1 and UE2) are shown respectively issuing PDU Session establishment requests to the AMF. When UE1 starts sending a PDU Session establishment request to AMF, AMF configures policy according to network administrator at H_(addr)The SMF position information corresponding to the Factors is not found in the Table, at the moment, the AMF will make a discovery request to the NRF, the NRF will return the discovered SMF _1 position information to the AMF, and the AMF will record the acquired SMF _1 and the Kp (m) and SMF _1 position information generated by the corresponding Factors into H_(addr)Table, and request to set up PDU Session to SMF _ 1.

When UE2 sends a PDU Session setup request, the fans carried in UE2 and Kp (m) generated by UE1 when communicating are the same, and AMF is at H_(addr)And obtaining SMF _1 position information in the Table, and sending a PDU Session establishment request to the SMF _ 1.

In FIG. 6, UE2 is based on cache H_(addr)The Table has the NF address information of the opposite end, so that a request message for finding the SMF _1 does not need to be sent to the NRF again, the speed of finding the SMF _1 by each other is accelerated NFs, and the efficiency of network communication is improved.

Other flows for creating the PDU Session are not the key points to be protected by the method of the present invention, and are not described herein, and if necessary, the TS23502 protocol flow can be consulted.

Fig. 7 shows AMF subscribing to SMF _1 status from NRF, and notifying AMF to update h (addr) Table when NRF receives SMF _1 status update, or NRF recognizes that SMF does not send heartbeat message (heartbeat is a term of art in communication, for example, a doctor recognizes that patient is alive when he recognizes heartbeat, and also in communication, a computer recognizes that another computer sends heartbeat message regularly, and then knows that another computer is not bad or powered off, and can communicate).

The above description is for the purpose of illustrating embodiments of the invention and is not intended to limit the invention, and it will be apparent to those skilled in the art that any modification, equivalent replacement, or improvement made without departing from the spirit and principle of the invention shall fall within the protection scope of the invention.

Claims

1. A method for accelerating NFs discovery in a 5G core network, comprising: the method comprises the following steps:

step S3, judging whether the type of the NF of the opposite terminal exists in the self cache of the step S2, if so, combining the corresponding key value template and the reference factor in the self cache to generate the key value of the cache mapping table, and turning to the step S4; otherwise go to step S5; the generation method of the key value of the cache mapping table comprises the following steps: substituting the reference factor for the placeholder in the key value template through a programming language interface to generate a key value in a cache mapping table;

step S5, the NF sends an opposite end NF discovery request to the NRF, the NRF returns the position and state information of the opposite end NF according to the NF request, and the NRF returns the result to directly communicate with the opposite end NF;

the step of generating the key-value template in the initialization stage comprises:

step S202, generating a policy table in a cache;

2. The method of claim 1, wherein the method for accelerating NFs discovery in a 5G core network comprises: the step S5 further includes a step of updating the cache mapping table according to the result returned by the NRF.

3. The method of claim 2, wherein the method for accelerating NFs mutual discovery in a 5G core network comprises: the step of updating the cache mapping table is as follows: when the NF receives the information of the NF position and the state of the opposite terminal returned by the NRF, the NF firstly decodes the information, then generates a key value according to the decoded reference factor and the key value template in the cache, and updates the generated key value into a cache mapping table.

4. The method of claim 1, wherein the method for accelerating NFs discovery in a 5G core network comprises: the mapping value is the IP address of the opposite end NF or the fully qualified domain name.