WO2007107041A1

WO2007107041A1 - A method for implementing call agent based on the media gateway control protocol and a system thereof

Info

Publication number: WO2007107041A1
Application number: PCT/CN2006/000458
Authority: WO
Inventors: Mingdong Li; Rongjun Zhu; Jun Hong
Original assignee: Zte Corporation
Priority date: 2006-03-22
Filing date: 2006-03-22
Publication date: 2007-09-27

Abstract

A method for implementing call agent based on the media gateway control protocol and a system thereof, the method includes: the network transmitting module is used as the only external gateway control protocol interface of the call agent system; the different data configure is made in the network transmitting module according to the types of the media gateway; the network transmitting module could transmit the protocol flow of the media gateway that the IP address could be inquired to the corresponding protocol processing module, thereby the IP route based transport layer distributing is implemented; the media gateway protocol flow that the IP address could not be inquired is transmitted to the protocol distributing module by polling; the protocol distributing module finishes the application layer distributing based on the media gateway control protocol analyze, thereby the protocol flow that the IP address could not be inquired is transmitted to the corresponding protocol processing module. By using the present invention, the advantages of the IP route based transport layer distributing and the media gateway control protocol analyze based application layer distributing are integrated, and the disadvantages of them are avoided.

Description

Call agent implementation method and system based on media gateway control protocol

The present invention relates to gateway control techniques and, more particularly, to an architecture design method for implementing a call agent based on a media gateway control protocol. Background technique

The Media Gateway Control Protocol is the RFC3435 protocol of The Internet Engineering Task Force (IETF). The Call Agent (CA) is a control device defined by the Media Gateway Control Protocol.

Figure 1 shows the network diagram of the system for implementing the media gateway control protocol. The media gateway control protocol adopts the idea of split gateway, which decomposes the gateways that have been processed by the previous signaling and media into two parts: Media Gateway (MG) and Call Agent (CA). The CA processes the signaling, the MG processes the media, and the CA controls the actions of the MG. In essence, the media gateway control protocol is a master/slave relationship. The CA sends a command to the MG to execute, and the MG reports the collected message to the CA. CA is equivalent to master (master), and MG is equivalent to slave (slave;). The CA assigns the MG a specific task and processes the request handed over by the MG. Both the CA and the MG are network elements in the network, which communicate with each other through a gateway control protocol.

Messages between the Call Agent and the Media Gateway include commands and responses. Its format is:

MGCPCommandLine II MGCPVerb 1氺(WSP) transaction-id 1* (WSP)

endpointName 1* (WSP) MGCPversion E0L MGCPResponseLine = responseCode 1* (WSP) transaction-id

[1* (WSP) 7〃 packageName] ; Only for 8xx [WSP responseString] E0L

Transaction-id two 1*9 (DIGIT)

endpointName = LocalEndpointName 〃@〃 DomainName

It can be seen that the command MGCPCommandLine always has the terminal's endpointName, and the endpointName contains the DomainName, the domain name, and the response MGCPResponseLine does not have any fixed identifier. There are different types of media gateways, including a large-capacity trunking gateway (TG) and a large-capacity access gateway (AG), and an integrated access device (Integrated Access Device). The IAD (Integrated Access Device) can allow dynamic IP addresses (through the Dynamic Host Configuration Protocol, DHCP protocol). In actual use, the Call Agent controls a large number of fixed-capacity TGs and AGs with a fixed number of IP addresses, while controlling a large number of small-capacity IADs (IAD addresses can be obtained by DHCP).

The call agent architecture is the core technology for implementing call agents. The distribution mode of the media gateway control protocol is an important part of the call agent architecture. For IP bearer-based call agents, existing distribution methods include transport layer distribution based on IP routing and application layer distribution based on media gateway control protocol parsing. The transport layer distribution of IP routing is simple to implement. It is suitable for controlling large-capacity TGs and AGs with a small number of fixed IP addresses through static route configuration. However, for a large number of small-capacity IADs, a large amount of data needs to be configured, which is inefficient and at the same time. Device support for dynamic addresses is difficult. The application layer distribution based on the media gateway control protocol parsing needs to parse the media gateway control protocol to obtain the distribution route, and obtain relatively comprehensive distribution data, which is suitable for providing routes for devices without static route configuration, but the implementation manner is complicated and the efficiency is low. , is not suitable for controlling large capacity TG and AG with a small number of fixed IP addresses. How to take advantage of these two distribution methods while avoiding their shortcomings is the goal of the call agent's architecture design.

Invention disclosure

The technical problem to be solved by the present invention is to provide a call agent implementation method and a call proxy system based on a media gateway control protocol, and to solve application layer distribution based on IP route-based transport layer distribution and media gateway control protocol parsing. Technology cannot synthesize the advantages of both distribution methods and circumvent the technical problems of its shortcomings.

To achieve the above object, the present invention provides a call agent implementation method based on a media gateway control protocol, which is characterized in that: the network forwarding module is used as an externally unique gateway control protocol interface of a call proxy system, according to the type of the media gateway. The network forwarding module performs corresponding data configuration, and the network forwarding module forwards the protocol flow of the media gateway of the queried IP address to the corresponding protocol processing module to implement transmission layer distribution based on the IP route, and the query is not IP to The protocol stream of the media gateway of the address is sent to the protocol distribution module in a round-robin manner, and the protocol distribution module completes the application layer distribution based on the media gateway control protocol parsing, thereby forwarding the protocol flow that cannot query the IP address to the corresponding Protocol processing module.

The above method is characterized in that: the corresponding data configuration includes: · configuring a static IP address data for a small number of large-capacity access gateways and relay gateways; for a large number of small-capacity integrated access devices, not Configuration.

The above method is characterized in that it further comprises the following steps:

Step 1: Configure corresponding data in a physical entity of each module of the call proxy system, configure a correspondence between a media gateway IP address and a corresponding protocol processing module in the network forwarding module, and configure a media gateway domain name and a corresponding protocol in the protocol distribution module. Processing the correspondence between the modules, and configuring protocol-related data and corresponding authentication data on each protocol processing module;

Step 2: The gateway protocol flow outside the call proxy system enters the network forwarding module. Step 3: The network forwarding module may query the IP address according to the configured media gateway IP address and the corresponding relationship of the corresponding protocol processing module. The protocol stream of the media gateway is forwarded to the corresponding protocol processing module; the protocol stream of the media gateway that cannot be queried is sent to the protocol distribution module in a round robin manner;

Step 4: The protocol distribution module completes the application layer distribution based on the media gateway control protocol parsing, and forwards the protocol flow to the corresponding protocol processing module.

Step 5: The protocol processing module processes the protocol data stream;

Step 6: Send the response of the protocol processing module to the protocol data stream directly to the network forwarding module.

The foregoing method is characterized in that: the step 4 further includes: the protocol distribution module parses the protocol to obtain a protocol special identifier, and obtains a corresponding protocol according to the configured media gateway domain name or the corresponding relationship between the response transaction and the corresponding protocol processing module. The module forwards the protocol stream to the corresponding protocol processing module.

The foregoing method is characterized in that, before the step 5, the step of authenticating the protocol data stream by the protocol processing module is further included.

The above method is characterized in that the media gateway supports a dynamic host configuration protocol.

The foregoing method is characterized in that, in the step 1, the network forwarding module further includes the steps of configuring the forwarding mode and the forwarding data to ensure that the forwarding is performed after the number of the corresponding forwarding modules changes. The data is not lost.

The foregoing method is characterized in that: the change of the number of the forwarded modules refers to: the protocol distribution module is expanded, and the number of faults is increased or decreased.

The above method is characterized in that it further comprises special processing steps for the transaction number, including: adding the identification information of the protocol processing module to the transaction number in the command of the call agent system to the media gateway, so that the call proxy system sends the information to the media gateway. The final transaction number is a combination of the protocol processing module information plus the actual transaction number generated by the call proxy system, so that the protocol distribution module can resolve the actual processing in the final transaction number when receiving the response from the media gateway to the call proxy system. The protocol processes the module information and forwards the Media Gateway Control Protocol message to the corresponding protocol processing module.

In order to better achieve the object of the present invention, the present invention further provides a call proxy system based on a media gateway control protocol, which is characterized in that it comprises: a network forwarding module, a protocol processing module, a protocol distribution module, and a data module; The data module is configured to implement a function of loading, managing, storing, and synchronizing data; using the network forwarding module as an externally unique gateway control protocol interface of the call proxy system, and correspondingly performing the network forwarding module according to the type of the media gateway Data configuration, the network forwarding module forwards the protocol flow of the media gateway of the queried IP address to the corresponding protocol processing module to implement the transport layer distribution based on the IP route, and the media gateway that will not query the IP address The protocol stream is sent to the protocol distribution module in a round-robin manner, and the protocol distribution module completes the application layer distribution based on the media gateway control protocol parsing, thereby forwarding the protocol flow that cannot query the IP address to the corresponding protocol processing. Module.

The above-mentioned call proxy system is characterized in that: the authentication module is further configured to: perform authentication on the media gateway; the network forwarding module is connected to the media gateway and the data module; the protocol distribution module and the network forwarding module, The protocol processing module, the authentication module, and the data module are connected; the authentication module is connected to the protocol processing module and the data module; and the data module is connected to all modules and distributed on physical entities of all modules.

The advantages of the invention are:

Compared with the prior art, the present invention distributes the processing of the media gateway control protocol twice, and distributes the network forwarding module based on the IP layer and the application layer (the PPM module identifier in the media gateway domain name and protocol transaction-id). The protocol forwards the module's distribution and performs different processing (directional forwarding or round-robin forwarding) for the forwarding mode. It can support the need to control different kinds of media gateways. For small quantities of large capacity AG and TG, use static in the network forwarding module NTM The state configuration can be forwarded to a fixed one or more protocol processing modules through the IP layer in one direction or in a round robin manner, which can improve processing efficiency. For a large number of small-capacity IADs, the forwarding relationship cannot be statically configured in the NTM, and the default is forwarded to the protocol distribution module PDM by directional or round-robin, which can reduce the logic complexity of the NTM module forwarding module and improve the forwarding efficiency of the NTM. By configuring different numbers of PDMs, the protocol forwarding efficiency of the protocol distribution module can also be guaranteed. In addition, due to application-level protocol forwarding at PDM, it is possible to support IADs that are registered by DHCP, and to support the nomadic functions of IAD terminals without changing the data configuration and conditions. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic diagram of a media gateway control protocol;

2 is a schematic structural diagram of a call agent module of the present invention;

3 is a flow chart of a call agent receiving protocol of the present invention;

4 is a flow chart of the call agent gateway control protocol processing of the present invention. The best way to implement the invention

The architecture design method of the call agent based on the media gateway control protocol of the present invention will be described below with reference to the accompanying drawings.

The Chinese and English names of the relevant modules are as follows:

Network Transmiting Module (NTM)

Protocol Distributing Module (PDM)

Protocol Processing Module (PPM)

Authentication Module (AM)

Data Module (DM)

As shown in FIG. 2, the architecture of the call proxy based on the media gateway control protocol of the present invention includes: a data module, which is globally distributed on all module entities, and provides data support and configuration for system operation;

The network forwarding module NTM processes the IP transport layer forwarding of the data stream, and provides multiple forwarding modes for the protocol processing module PPM and the protocol distribution module PDM, including directional forwarding for one module, or round-robin forwarding for multiple modules. And the forwarding mode and the forwarding data can be configured. When the number of the corresponding forwarding modules changes, for example, the protocol distribution module PDM is expanded and faulty. To increase or decrease the number, ensure that the forwarding data is not lost.

The protocol distribution module PDM processes the protocol application layer forwarding of the data stream, parses the gateway control protocol, and forwards the protocol to the final processing module through the media gateway domain name and the PPM module identifier in the protocol transaction-id; in general, it needs to be configured. Protocol distribution module PDM (convenient for network forwarding module NTM round-robin transmission);

The concept of the media gateway domain name and the PPM module identifier in the protocol transaction-id are required to be forwarded by the protocol application layer. For the MG-to-CA command, it can be considered as the association between the media gateway domain name and the protocol distribution module PDM; In the response of the CA, since the protocol message has no fixed identifier, the present invention provides special processing for the transaction transaction-id. In the CA to MG command, the transaction id is added to the identification information of the protocol processing module PPM, that is, the CA is sent to the MG. The final transaction-id is the combination of the protocol processing module PPM information plus the actual transaction-id generated by the CA, so that the protocol distribution module PDM can resolve the actual processing in the final transaction-id when receiving the response from the MG to the CA. The protocol processes the module PPM information and forwards the Media Gateway Control Protocol message to the corresponding protocol processing module PPM.

The protocol processing module PPM, which finally completes the processing of the protocol, performs a protocol response or initiates a new protocol request. Generally, multiple protocol processing modules PPM need to be configured;

The authentication module AM authenticates the protocol, and the authentication data and protocol processing module PPM can be configured together. When the media gateway registers (DHCP) through a changed IP address, the protocol can be authenticated through the authentication module.

3 is a call flow receiving protocol flow diagram (excluding transmission) of the present invention. As shown in the figure, the architecture implementation method of the call proxy based on the media gateway control protocol includes the following steps:

Step A. Configure the corresponding data in the physical entity of each module of the call proxy, configure the correspondence between the IP address of the media gateway and the corresponding protocol processing board in the network forwarding module, and configure the domain name of the media gateway and the corresponding protocol processing board in the protocol distribution module PDM. Relationship, configuring protocol related data and corresponding authentication data on each protocol processing module PPM;

Step B. The gateway protocol flow outside the system enters the network forwarding module NTM;

Step C. The network forwarding module NTM forwards the protocol flow of the media gateway of the queried IP address to the corresponding protocol processing module PPM according to the corresponding relationship between the configured media gateway IP address and the corresponding protocol processing board;

Step C'. The network forwarding module NTM will not be able to query the protocol flow of the media gateway through the round robin The mode is sent to the protocol distribution module P;

Step D. The protocol distribution module PDM parses the protocol to obtain a protocol special identifier, and obtains a corresponding protocol processing module PPM according to the configured media gateway domain name or the correspondence between the transaction transaction-id and the corresponding protocol processing module, and forwards the protocol flow. To the corresponding PPM;

Step E. If required (such as the media gateway supports DHCP), the PPM authenticates the protocol data stream. (this step is optional)

Step F. PPM processes the protocol data stream.

Step G. The response of the PPM to the protocol data stream is sent directly to the network forwarding module NTM.

As shown in FIG. 4, the process of the gateway control protocol message entering the architecture design method of the call agent based on the media gateway control protocol of the present invention is as follows:

Step 401: The system completes various data configurations and runs normally.

Step 402: The network forwarding module receives the media gateway control protocol sent by the media gateway.

Oh;

Step 403: The data module of the network forwarding module DM queries the IP address of the media gateway to determine whether the IP address of the media gateway is configured. If yes, go to step 404. Otherwise, go to step 406.

Step 404: The data module DM configures the media gateway IP address, and sends the media gateway control protocol message to the corresponding protocol processing module PPM.

Step 405: The protocol processing module PPM completes the final protocol processing. If there is a response, it is directly sent to the network forwarding module NTM, and the process proceeds to step 410.

Step 406: The data module DM does not configure the media gateway IP address, and sends the control protocol message to the corresponding protocol forwarding module PDM through the round robin.

Step 407: The protocol forwarding module PDM parsing protocol, if it is a command message, obtain the domain name of the media gateway, and query the correspondence between the media gateway and the PPM through the data module DM; if it is a response message, parse the relevant transaction-id from the transaction The protocol processes the module PPM information, and determines whether the PDM can query the final processed PPM information. If yes, step 408 is performed; otherwise, step 409 is performed.

Step 408: The PDM may query the final processed PPM information, and send the media gateway control protocol message to the corresponding protocol processing module PPM, and go to step 405.

Step 409: The PDM cannot query the PPM information that is finally processed, and the protocol forwarding module PDM Special handling of this message.

Step 410: The process ends.

Although the disclosed architecture design method for providing a call agent based on a media gateway control protocol is specifically described with reference to the embodiments, those skilled in the art will appreciate that the present invention can be practiced without departing from the scope and spirit of the present invention. It performs various obvious modifications of the form and details. For example, due to the improvement and update of the gateway control protocol by the IETF, the technical solution of the present invention is the same as the architecture design of the call agent for providing the media gateway control protocol based on the RFC3435 protocol. The same method applies. The embodiments described above are illustrative and not restrictive, and all changes and modifications are within the scope of the invention. Industrial applicability

The invention distributes the processing of the media gateway control protocol twice, distributes the network forwarding module based on the IP layer, and distributes the protocol forwarding module based on the application layer, and performs different processing on the forwarding mode (directional forwarding or round robin forwarding). ), can support the need to control different kinds of media gateways. For a small number of large-capacity AGs and TGs, the static configuration of the network forwarding module can be forwarded to a fixed one or more protocol processing modules through the IP plane in a directed or round-robin manner, which can improve processing efficiency. For a large number of small-capacity IADs, the NTM does not statically configure the forwarding relationship. Instead, the default forwarding or round-robin mode is forwarded to the protocol distribution module PDM, which can reduce the logic complexity of the NTM module forwarding module and improve the forwarding efficiency of the NTM. In summary, the present invention combines the advantages of IP layer-based transport layer distribution and application layer distribution based on media gateway control protocol parsing and circumvents the disadvantages of both distribution methods. The present invention is applicable to the technical field of gateway control, and the method of the present invention is equally applicable to other fields in which similar applications exist.

Claims

Claim

A call agent implementation method based on a media gateway control protocol, comprising: using a network forwarding module as an externally unique gateway control protocol interface of a call proxy system, and correspondingly performing the network forwarding module according to a type of the media gateway Data configuration, the network forwarding module forwards the protocol flow of the media gateway of the queried IP address to the corresponding protocol processing module to implement the transport layer distribution based on the IP route, and the media gateway that will not query the IP address The protocol stream is sent to the protocol distribution module in a round-robin manner, and the protocol distribution module completes the application layer distribution based on the media gateway control protocol parsing, thereby forwarding the protocol flow that cannot query the IP address to the corresponding protocol processing. Module.

2. The method according to claim 1, wherein the corresponding data configuration comprises: configuring a static IP address data for a small number of large-capacity access gateways and relay gateways; and for a large number of small capacity Integrated access device, no configuration.

3. The method according to claim 1, further comprising the steps of: Step 1: configuring corresponding data in a physical entity of each module of the call proxy system, configuring a media gateway IP address in the network forwarding module, and Corresponding relationship between the corresponding protocol processing module, configuring a correspondence between the media gateway domain name and the corresponding protocol processing module in the protocol distribution module, and configuring protocol related data and corresponding authentication data on each protocol processing module;

Step 2: The gateway protocol flow outside the call proxy system enters the network forwarding module. Step 3: The network forwarding module may query the IP according to the configured media gateway IP address and the corresponding relationship of the corresponding protocol processing module. The protocol flow of the media gateway of the address is forwarded to the corresponding protocol processing module; the protocol flow of the media gateway that cannot be queried is sent to the protocol distribution module in a round robin manner;

Step 5: The protocol processing module processes the protocol data stream;

In step 6, the response of the protocol processing module to the protocol data stream is directly sent to the network forwarding module.

The method according to claim 3, wherein the step 4 further comprises: the protocol distribution module parsing the protocol to obtain a protocol special identifier, according to the configured media gateway domain name Or responding to the correspondence between the transaction and the corresponding protocol processing module to obtain a corresponding protocol processing module, and forwarding the protocol flow to the corresponding protocol processing module.

The method according to claim 3 or 4, wherein the step 5 further comprises the step of the protocol processing module authenticating the protocol data stream.

6. The method of claim 5, wherein the media gateway supports a dynamic host configuration protocol.

The method according to claim 5, wherein the step 1 further includes the step of configuring, by the network forwarding module, the forwarding mode and the forwarding data, to ensure that when the number of the corresponding forwarding modules changes, forwarding The data is not lost.

The method according to claim 7, wherein the change in the number of the forwarded modules refers to: the protocol distribution module is expanded, and the number of faults is increased or decreased.

9. The method according to claim 1, further comprising the special processing step of the transaction number, comprising: adding the transaction number to the identification information of the protocol processing module in the command of the call agent system to the media gateway, thereby calling The final transaction number sent by the proxy system to the media gateway is the combination of the protocol processing module information plus the actual transaction number generated by the call agent system, so that the protocol distribution module can be in the final transaction when receiving the response from the media gateway to the call agent system. The number resolves to the actual processed protocol processing module information and forwards the Media Gateway Control Protocol message to the corresponding protocol processing module.

A call agent system based on a media gateway control protocol, comprising: a network forwarding module, a protocol processing module, a protocol distribution module, and a data module;

The data module is configured to implement a function of loading, managing, storing, and synchronizing data; using the network forwarding module as an externally unique gateway control protocol interface of the call proxy system, and the network forwarding module according to the type of the media gateway Performing corresponding data configuration, the network forwarding module forwards the protocol flow of the media gateway of the queried IP address to the corresponding protocol processing module to implement the transport layer distribution based on the IP route, and the IP address that cannot be queried The protocol stream of the media gateway is sent to the protocol distribution module in a round-robin manner, and the protocol distribution module completes the application layer distribution based on the media gateway control protocol parsing, thereby forwarding the protocol flow that cannot query the IP address to the corresponding protocol. Processing module.

The call agent system according to claim 10, further comprising: an authentication module, configured to implement authentication of the media gateway; The network forwarding module is connected to the media gateway and the data module, and the protocol distribution module and the network forwarding module, the protocol processing module, the authentication module, and the data module are connected; the authentication module is connected to the protocol processing module and the data module; The data module is connected to all modules and is distributed on the physical entities of all modules.