CN110167052B - A kind of AMF network element deployment system and operation method based on pool technology - Google Patents

Abstract

The invention discloses an AMF network element deployment system based on pool technology and an operation method thereof, comprising an AMF node pool and an AMF node control module connected with the AMF node pool; a plurality of AMF nodes are arranged in the AMF node pool and are respectively connected with the AMF node control module; the AMF node comprises a network interface layer, a protocol analysis layer and an application function layer which are sequentially connected, and the AMF node control module is arranged at the application function layer of the AMF node control center; the AMF node control module comprises a service registration discovery module and an automatic expansion control module; the invention can realize automatic expansion and contraction according to real-time performance in the system by performing virtualization design on the AMF nodes, and meanwhile, when a certain AMF node fails, a new AMF node can replace the failed AMF node through service call to continue providing service for the UE, and the UE does not need to perform registration, identity authentication and other operations to the network side again, thereby avoiding frequent signaling interaction process caused by network side failure.

Description

A kind of AMF network element deployment system and operation method based on pool technology

technical field

The invention belongs to the technical field of network communication, in particular to an AMF network element deployment system and operation method based on a pool technology.

Background technique

The traditional 4G core network elements such as MME are coupled with dedicated hardware. The update and upgrade of the network must involve the replacement of equipment. The high coupling between network functions and hardware is not conducive to subsequent maintenance work. The 5G core network draws on the design concept of microservices and reconstructs traditional network elements. Microservices are an approach to developing a single application as a set of small services, each running in its own process and communicating with a lightweight mechanism (usually an API for HTTP resources). Traditional network elements are divided into more lightweight network functions, and network functions are defined as relatively independent service modules that can be flexibly invoked. For example, in 4G, MME network elements have access control functions, mobility management functions, and session management functions. , In 5G, the MME entity is divided into two independent modules, AMF and SMF, in which AMF is used to handle user access and mobility management, and is responsible for processing user registration requests and identity authentication; SMF establishes an N4 interface connection with the user plane. to manage PDU sessions. The AMF network function and the SMF network function interact with each other through service-oriented interfaces. The design of this microservice has better independent scalability and improves the efficiency of the interface.

In the 4G network, in order to solve the problem of inability to work due to the failure of a single-point MME, the concept of MME pool is introduced. Multiple MMEs form an MME pool. All MMEs in the pool jointly serve the area served by the pool. No re-attachment process is required when moving within the area served by the pool.

MME pool technology has been widely used in 4G networks. Here is an introduction to the process of this technology to achieve load balancing.

Step 1: The MME in the MME POOL regularly obtains its own relative weight parameters, creates an S1 configuration update request message, carries the relative weight parameters, and sends the message to the eNodeB.

Step 2: The UE sends an attach request message to the eNodeB.

Step 3: After receiving the MME configuration update request message sent by the MME, the eNodeB parses the message, updates the corresponding MME relative weight parameter, and selects the MME access with the largest weight for the UE.

This technology effectively solves the MME single point of failure problem, and also ensures that each MME can evenly process requests in the network.

Pool technology solves the problem of MME overload, but due to the high coupling between MME and dedicated hardware in the 4G network, the number of MMEs in an MME POOL is fixed, and it is difficult to increase the number of MMEs in the pool. The number of MME nodes in the pool is dynamically adjusted according to user requests, and it is inconvenient to maintain. At the same time, with the continuous expansion of business requirements, hardware upgrades also need to be considered, so the operation and maintenance costs are too high for operators. When designing and deploying network functions in the existing core network, the above-mentioned defects have not yet been overcome, and further improvement is urgently needed.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an AMF network element deployment system and operation method based on the pool technology in view of the problem that services cannot be normally provided and service allocation when a single node of the core network fails. It can automatically scale in the system according to real-time performance. At the same time, when an AMF node fails, the new AMF node can replace the faulty AMF node and continue to provide services for the UE through service calls, and the UE does not need to re-register and identify with the network side. Verification and other operations avoid frequent signaling interactions due to network side failures.

For achieving the above object, the technical scheme adopted in the present invention is:

An AMF network element deployment system based on pool technology, comprising an AMF node pool and an AMF node control module connected to the AMF node pool; the AMF node pool is provided with several AMF nodes, and the several AMF nodes are respectively connected with the AMF nodes The control module is connected; the AMF node includes a network interface layer, a protocol analysis layer and an application function layer that are connected in turn; the network interface layer is used for the AMF node and other network nodes (other network nodes refer to UE-side network nodes and AMF nodes control module); the protocol parsing layer is used to parse and package the data transmitted between the protocol parsing layer, the network interface layer and the application function layer; the application function layer is used for AMF access management, service invocation and timing monitoring; the AMF node control module includes a service registration discovery module and an automatic scaling control module; the service registration discovery module is used to provide a service registration function and a service discovery function; the automatic scaling control module is used to The number of UEs that initiate the request adjusts the number of AMF nodes in the AMF node pool.

Specifically, the network interface layer includes an N2 interface and a Namf interface; the N2 interface is used for the connection between the AMF node and the RAN node; the Namf interface is used for the connection between the AMF node and the NF node.

Specifically, the protocol analysis layer includes a NAS message processing module, a NG-AP message processing module and an HTTP/2 message processing module; the NAS message processing module is connected with the NG-AP message processing module; the NG-AP message processing module Data is transmitted between the module and the N2 interface of the network interface layer through the SCTP protocol; data is transmitted between the HTTP/2 message processing module and the Namf interface of the network interface layer through the UDP protocol.

Specifically, the application function layer includes an access management module, a service invocation module and a scaling monitoring module; the access management module is used to implement the access management function of AMF; the service invocation module is used to implement an AMF node to Another AMF node invokes a service function; the scaling monitoring module is used to regularly monitor the CPU occupancy rate of the virtual machine where the current AMF node is located.

Specifically, the service registration discovery module provides a service registration function by defining a service registration discovery center in the configuration file of the service when each service is started, and then registering the node information of the service to the service registration center; The consumer end subscribes to the service to be called according to the configuration file, and the service registration and discovery module obtains the address information of the service to be called from the local cache, and executes the remote calling of the service.

Corresponding to the above-mentioned AMF network element deployment system, the present invention also provides an operation method of the AMF network element deployment system based on the pool technology, which specifically includes the following steps:

S1, the UE initiates a registration request to the first AMF node, the request is received by the network interface layer of the first AMF node, parsed by the protocol parsing layer, and finally sent to the application function layer by the protocol parsing layer;

S2, the application function layer initiates a series of NGAP commands to the UE. After the UE successfully responds to the NGAP command sent by the application function layer, it sends a registration completion message to the application function layer of the first AMF node. At this time, the UE normally obtains services from the network side ;

S3, when the application function layer monitors that the number of UEs connected to the first AMF node is too large, the first AMF node sends a request service migration message to the AMF node control module;

S4, the AMF node control module selects a currently relatively idle second AMF node in the AMF node pool, and notifies the second AMF node to replace the first AMF node and continue to provide services for the UE;

S5, the second AMF node obtains the registration message of the UE through the first AMF node, and informs the UE that the first AMF node no longer provides services at this time, and the second AMF node continues to provide services;

S6, the UE updates the AMF node identifier, and the UE is connected to the second AMF node and continues to obtain services from the network side.

Further, when the number of UEs connected to all AMF nodes in the AMF node pool is too much/too little, the AMF node control module calculates the most suitable number of AMF nodes in the AFM node pool according to the number of UEs connected in the current AMF node pool, And increase/decrease the number of AMF nodes in the AMF node pool through the automatic scaling control module.

Specifically, in step S1, the protocol parsing layer parses the registration request initiated by the UE through the NG-AP message processing module.

Specifically, in step S2, the NGAP instruction includes UE identity verification and UE context establishment.

Specifically, the AMF node control module selects a currently relatively idle AMF node according to the CPU occupancy rate of the virtual machine where the AMF node is located in the AMF node pool.

Compared with the prior art, the beneficial effects of the present invention are: (1) the present invention sets up a plurality of AMF nodes in an AMF node pool, and simultaneously monitors all AMF nodes through the AMF node control module, and detects each AMF node by detecting The number of AMF nodes in the AMF node pool is dynamically adjusted by the CPU usage of the virtual machine where it is located, which avoids the congestion of AMF node services caused by too many requests in the network and the waste of AMF node resources caused by too few requests in the network; (2 ) In the AMF node pool of the present invention, when a certain AMF node fails or the number of connections is too large, the new AMF node can call the new AMF node through the service to replace the faulty AMF node and continue to provide services for the UE, and the UE does not need to re-enter the network Registration and authentication are performed on the side, avoiding frequent signaling interactions due to network side failures.

Description of drawings

1 is a schematic block diagram of the overall structure of an AMF node of the present invention;

2 is a schematic block diagram of the overall structure of the AMF node control module of the present invention;

3 is a schematic block diagram of the overall structure of the AMF node pool of the present invention;

FIG. 4 is a schematic flowchart of a service migration method for an AMF node pool in Embodiment 2 of the present invention.

Detailed ways

The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1

As shown in Figures 1 to 3, this embodiment provides an AMF network element deployment system based on pool technology, including an AMF node pool and an AMF node control module connected to the AMF node pool; the AMF node pool is provided with Several AMF nodes, the several AMF nodes are respectively connected with the AMF node control module; the AMF nodes include a network interface layer, a protocol analysis layer and an application function layer that are connected in turn; the network interface layer is used for the AMF node and other network nodes. (Other network nodes refer to the communication between the UE-side network node and the AMF node control module); the protocol parsing layer is used to parse and package the data transmitted between the protocol parsing layer, the network interface layer and the application function layer; the application The functional layer is used for AMF access management, service invocation and timing monitoring; the AMF node control module includes a service registration discovery module and an automatic scaling control module; the service registration discovery module is used to provide a service registration function and a service discovery function; The automatic scaling control module is configured to adjust the number of AMF nodes in the AMF node pool according to the number of UEs that initiate requests to the core network side.

Specifically, the AMF node control module is set at the application function layer of the AMF node control center, the AMF node control center includes a network interface layer, a protocol analysis layer and an application function layer, the service registration discovery module and the automatic scaling control module. It is located at the application function layer; the protocol analysis layer is used to parse and package the communication messages between the AMF node control module and the AMF node; the network interface layer is used to obtain a communication connection with the AMF node.

Specifically, the network interface layer includes an N2 interface and a Namf interface; the N2 interface is used for the connection between the AMF node and the RAN node; the Namf interface is used for the connection between the AMF node and the NF node.

Specifically, the protocol analysis layer includes a NAS message processing module, a NG-AP message processing module and an HTTP/2 message processing module; the NAS message processing module is connected with the NG-AP message processing module; the NG-AP message processing module Data is transmitted between the module and the N2 interface of the network interface layer through the SCTP protocol; data is transmitted between the HTTP/2 message processing module and the Namf interface of the network interface layer through the UDP protocol.

Specifically, the application function layer includes an access management module, a service invocation module and a scaling monitoring module;

The access management module is used to realize the access management function of AMF, and has interface management function, UE context management function, UE message initialization function, NAS transmission function, UE request registration/deregistration function and identity verification function; When sending the first NAS message registration request message, the N2 interface connection needs to be established between the RAN node and the AMF node. When the RAN node receives the first NAS message from the UE, it will initiate the initial UE message flow, which belongs to NGAP At the same time, the NAS message is encapsulated in the NAS PDU information element of the NGAP message, which is transparently forwarded by the RAN node. After receiving the initial UE message, the AMF node parses the RAN NGAP UE ID and checks whether the UE has executed the initial UE message. If not, allocate the structure for the UE to store the relevant information of the UE. Then the AMF node initiates an identity request to the UE through downlink NAS transmission, and the UE responds to the identity message after receiving the message. After receiving the UE identity response, the AMF node initiates an initial UE context request message to the UE, and sends a registration reception message, that is, the UE accesses the AMF node.

The service invocation module is used to realize the function of one AMF node calling service to another AMF node. When the AMF node provides services to the outside world, the AMF node is the service provider, and the service provider is responsible for providing service information (service name) for the service provider. , IP address, etc.) registration, service port and other operations; when AMF consumes a service, it acts as a service consumer. If the service consumer wants to call a service, it needs to have relevant information about the calling service, such as the address of the service method;

The scaling monitoring module is used to regularly monitor the CPU occupancy rate of the virtual machine where the current AMF node is located, and then the value and the information of the AMF node are packaged into an HTTP message and sent to the automatic scaling control module in the AMF node control module, and the automatic scaling control The module updates the information of the current AMF node after receiving the message, and judges whether it needs to perform the scaling operation according to the latest value of the CPU usage of the virtual machine where the current AMF node is located; when all the AMF nodes in the AMF node pool are connected to too many UEs When / is too small, the AMF node control module calculates the most suitable number of AMF nodes in the AFM node pool according to the number of connected UEs in the current AMF node pool, and increases/decreases the number of AMF nodes in the AMF node pool through the automatic scaling control module.

Specifically, the service registration discovery module provides a service registration function by defining a service registration discovery center in the configuration file of the service when each service is started, and then registering the node information of the service to the service registration center; The consumer end subscribes to the service to be called according to the configuration file, and the service registration and discovery module obtains the address information of the service to be called from the local cache, and executes the remote calling of the service.

Example 2

As shown in FIG. 4 , this embodiment provides a service migration method of an AMF network element deployment system based on a pool technology, and the method specifically includes the following steps:

Step 1: The AMF node that is providing users cannot continue to provide services due to some problems (congestion or failure caused by too many connections). Address information;

Step 2: The control center selects the AMF node with low CPU usage in the AMF node pool at this time;

Step 3: The control center sends a notification to the selected new AMF node, the message includes the IP address where the old AMF node is located, and notifies the new AMF node to go to the old AMF node to obtain the user's context information.

Step 4: the service invocation module of the new AMF node obtains the services that the old AMF node can provide through the service registration discovery module of the control center, and calls the service from the old AMF node through the API interface to obtain the context information of the UE;

Step 5: the old AMF node responds to the data requested by the new AMF node, and the information of the user UE already exists in the new AMF node at this time;

Step 6: The old AMF node informs the user that the UE itself cannot provide services at this time, provides the UE with a new AMF node address, and informs the UE to continue to obtain services from the new AMF node;

Step 7: The user UE initiates a service request to the new AMF to obtain the service. Since the new AMF node has obtained the UE context from the old AMF node at this time, the UE does not need to perform the initial UE message, identity verification, establishment of the UE context and other processes. , the UE is connected to a new AMF node and continues to obtain services from the network side.

In this embodiment, in the AMF node pool of this embodiment, when a certain AMF node fails or the number of connections is too large, the new AMF node can call the new AMF node through the service to replace the faulty AMF node and continue to provide services for the UE, while The UE does not need to perform operations such as registration and identity verification with the network side again, which avoids frequent signaling interactions due to network side failures.

Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, and substitutions can be made in these embodiments without departing from the principle and spirit of the invention and modifications, the scope of the present invention is defined by the appended claims and their equivalents.

Claims (10)

1. An AMF network element deployment system based on pool technology is characterized by comprising an AMF node pool and an AMF node control module connected with the AMF node pool; a plurality of AMF nodes are arranged in the AMF node pool and are respectively connected with the AMF node control module; the AMF node comprises a network interface layer, a protocol analysis layer and an application function layer which are connected in sequence; the network interface layer is used for communication between the AMF node and other network nodes; the protocol analysis layer is used for analyzing and packaging data transmitted between the protocol analysis layer and the network interface layer as well as the application function layer; the application function layer is used for access management, service calling and timing monitoring of the AMF; the AMF node control module comprises a service registration discovery module and an automatic expansion control module; the service registration discovery module is used for providing a service registration function and a service discovery function; and the automatic scaling control module is used for adjusting the quantity of the AMF nodes in the AMF node pool according to the quantity of the UE initiating the request to the core network side.

2. The AMF network element deployment system based on pool technology as claimed in claim 1, wherein said network interface layer comprises N2 interface and Namf interface; the N2 interface is used for connection between the AMF node and the RAN node; the Namf interface is used for connecting the AMF node and the NF node.

3. The AMF network element deployment system based on pool technology as claimed in claim 1, wherein the protocol parsing layer comprises a NAS message processing module, a NG-AP message processing module and a HTTP/2 message processing module; the NAS message processing module is connected with the NG-AP message processing module; the NG-AP message processing module transmits data with an N2 interface of a network interface layer through an SCTP protocol; and the HTTP/2 message processing module transmits data with a Namf interface of a network interface layer through a UDP protocol.

4. The AMF network element deployment system based on pool technology as claimed in claim 1, wherein said application function layer comprises an access management module, a service invocation module and a flexible monitoring module; the access management module is used for realizing the access management function of the AMF; the service calling module is used for realizing the function of calling service from one AMF node to another AMF node; the flexible monitoring module is used for regularly monitoring the CPU occupancy rate of the virtual machine where the current AMF node is located.

5. The AMF network element deployment system based on pool technology as claimed in claim 1, wherein the service registration discovery module provides a service registration function by defining a service registration discovery center in a configuration file of each service when the service is started, and then registering node information of the service to the service registration center; and the service consumer side subscribes the service to be called according to the configuration file, and the service registration discovery module acquires the address information of the service to be called from the local cache and executes the remote calling service.

6. An operation method of an AMF network element deployment system based on a pool technology, the operation method being based on the AMF network element deployment system of claim 1, characterized by comprising the steps of:

s1, UE initiates a registration request to the first AMF node, the request is received by the network interface layer of the first AMF node, then is analyzed by the protocol analysis layer, and finally is sent to the application function layer by the protocol analysis layer;

s2, the application function layer sends a series of NGAP commands to the UE, after the UE successfully responds to the NGAP commands sent by the application function layer, the UE sends a registration completion message to the application function layer of the first AMF node, and at this time, the UE normally obtains services from the network side;

s3, when the application function layer monitors that the number of the UE connected with the first AMF node is excessive, the first AMF node sends a service migration request message to the AMF node control module;

s4, the AMF node control module selects a second AMF node which is idle at present in the AMF node pool, and informs the second AMF node to replace the first AMF node to continue to provide service for the UE;

s5, the second AMF node obtains the registration message of the UE through the first AMF node, and informs the UE that the first AMF node does not provide service at this time, and the second AMF node continues to provide service;

and S6, the UE updates the AMF node identification, and the UE is connected with the second AMF node to continue to acquire service from the network side.

7. The method for operating the AMF network element deployment system based on the pool technology as claimed in claim 6, further comprising:

when the number of the UE connected with all the AMF nodes in the AMF node pool is excessive/insufficient, the AMF node control module calculates the most appropriate number of the AMF nodes in the AFM node pool according to the number of the UE connected with the AMF node pool at present, and increases/reduces the number of the AMF nodes in the AMF node pool through the automatic expansion control module.

8. The method of claim 6, wherein in step S1, the protocol resolution layer resolves the registration request initiated by the UE through the NG-AP message processing module.

9. The method of claim 6, wherein in step S2, the NGAP command includes UE identity authentication and UE context establishment.

10. The method according to claim 6, wherein in step S4, the AMF node control module selects the current relatively idle AMF node according to a CPU occupancy of a virtual machine in which the AMF node in the AMF node pool is located.

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