CN1553668A - A method for intercommunication between virtual media gateways - Google Patents

Abstract

The present invention relates to a method for intercommunication between virtual media gateways (VMGWs), which realizes internal intercommunication between VMGWs inside the same physical media gateway (MGW), including the steps of: configuring internal bearer resources for intercommunication between VMGWs in the MGW ; The media gateway controller (MGC) obtains the above configuration information; the MGW judges whether the internal endpoint is operated according to the configuration information and the message sent by the MGC, and if it is judged to increase an internal endpoint, further judges whether its partner endpoint exists If the partner endpoint exists, the contexts of the two internal endpoints are associated and merged into one context. When forwarding bearer information inside the MGW, only the merged context is used without processing by the internal endpoints, that is, the information is directly forwarded between two external endpoints to achieve the purpose of internal intercommunication.

Description

A method for intercommunication between virtual media gateways

technical field

The invention relates to core network equipment MGW and MGC in WCDMA system and NGN system, and a method for supporting virtual media gateway internal intercommunication on the MGW equipment.

Background technique

In the WCDMA system and the NGN system, the switching equipment of the core network realizes the separation of bearer and control functions, that is, the original switching equipment is separated into two devices MGC and MGW, the MGC implements the call control function, and the MGW implements the bearer control and bearer interaction functions , the bearer medium supported by the MGW may be TDM, ATM or IP, and the MGC controls the MGW through the H.248/MGCP protocol. The structure after separation in the WCDMA system is shown in Figure 1. in the picture

GERAN: GSM access network;

UTRAN: WCDMA access network;

HLR: Home Location Register.

The general communication process of two MGWs is briefly described as follows: Assume that there are two MGWs, namely MGW1 and MGW2, and the bearer between them is TDM (namely, Nb interface). The two MGWs are controlled by the same MGC. Between MGW and MGC The communication interface is Mc interface, and the communication protocol is H.248. When User1 at MGW1 needs to communicate with User2 at MGW2, the call control process is shown in Figure 2:

(1) MGC selects gateway MGW1 on User1 side, notifies MGW1 to add endpoint T1 on User1 side, and returns to MGC after MGW finishes;

(2) The MGC selects the gateway MGW2 on the User2 side, and notifies MGW1 to increase the bearer endpoint T2 linked with MGW2, and MGW1 automatically sets T1 and T2 as the connected state, and returns to MGC after completion;

(3) The MGC notifies MGW2 to add the bearer endpoint T3 connected to MGW1. In the case of TDM bearer, the T2 endpoint and T3 endpoint on MGW1 are in the connection state by default, and return to the MGC after completion;

(4) The MGC notifies the MGW2 to add the endpoint T4 on the User2 side, then connects the T3 and T4 endpoints, and returns to the MGC. In this way, two users establish a connection relationship through four endpoints;

(5) Other processes are omitted here.

According to the protocol, one MGW is controlled by only one MGC. If one MGW is to be controlled by multiple MGCs, virtual media gateways need to be divided, that is, a physical media gateway device is divided into multiple logical media gateway devices. Each logical media gateway is called a virtual media gateway (VMGW), and can be independently controlled by an MGC device. In this way, two VMGW entities on the same physical MGW device are equivalent to two independent MGW devices for MGC, they need to be able to communicate with each other, and for MGC devices, their mutual communication is considered as communication between devices .

There are many applications of VMGW intercommunication. For example, when MGW is used as an integrated gateway office, NGN and WCDMA systems need to communicate through this MGW, then two VMGWs can be drawn, and each VMGW is controlled by the MGC of the NGN system and by the control of the WCDMA system. MGC control, the problem of intercommunication between two systems becomes the problem of intercommunication between VMGWs.

The intercommunication of two VMGWs can be used as two independent devices for external communication. One way to achieve intercommunication is to set the bearer resources between them as IP, and through the routing loopback of the external IP network, the IP sent from one VMGW can be The packet is sent to another VMGW without special processing inside the MGW. However, this method of intercommunication through the external network has obvious disadvantages. First, if the VMGW originally supports IP bearer, and then uses IP bearer for intercommunication, there will be two directions of a VMGW for IP bearer, and according to the standard MGC will increase The IP endpoint command does not specify the direction of the IP endpoint, so unless the MGC carries additional information, such as specifying the identity or office direction of the IP network, the MGW has no way to handle this situation; in addition, two logical entities within a physical device The communication needs to rely on the external network, which is obviously unreasonable, that is, the communication capability of the equipment used for intercommunication and the carrying resources of the external network are wasted, and the communication delay will increase. Therefore, a simple and efficient internal intercommunication method is needed.

Contents of the invention

The purpose of the present invention is to provide a method for internal intercommunication between VMGWs in the same physical MGW, which can effectively reduce resource consumption and communication delay of communication between two VMGWs.

The method for realizing internal intercommunication between VMGWs of the present invention includes the following steps:

A) Configuring internal bearer resources for intercommunication between VMGWs in the MGW;

B) the media gateway controller (MGC) obtains the above configuration information;

C) The MGW judges whether the operation is performed on the internal endpoint according to the configuration information and the message issued by the MGC, and if not, returns a response message after processing the normal message; if yes, proceeds to step D;

D) judging whether to add an internal endpoint, if not, then return the response message after the internal endpoint is processed according to the normal operation process; if yes, then proceed to step E;

E) Judging whether the partner endpoint exists, if not, then increase the endpoint message processing normally, insert the endpoint information into an internal endpoint information table, and return a response message; if yes, associate and merge the contexts of the two internal endpoints Create a context, through which external endpoints communicate directly during voice or data forwarding, and then return a response message.

The internal bearer resources may be IP bearers, ATM bearers or TDM bearers.

The step B can be realized by configuring the internal bearer resource consistent with the MGW on the MGC or obtaining the resource configuration of the MGW through the audit function of the media gateway control protocol.

The step C determines whether the operation is performed on an internal endpoint, including:

C1) According to the TDM bearer time slot search configuration information on the MGW to judge;

C2) according to the configuration information that ATM bears the weight of, judge whether internal bearer, if so, then the ATM end point that distributes on this bearer is exactly internal end point, otherwise is external end point;

C3) According to the configuration information of the IP bearer, it is judged whether it is an internal bearer, if yes, the IP endpoint allocated on this bearer is an internal endpoint, otherwise it is an external endpoint.

In the step C2, if there is only one ATM bearer network, then judge according to the configuration of the ATM bearer network; if there are multiple ATM bearer networks, then at first search for the configuration of the corresponding ATM bearer network according to the office direction information carried in the message information, and then judge whether it is an internal bearer according to the configuration information; in the step C3, if there is only one IP bearer network, then judge according to the configuration of the IP bearer network; if there are multiple IP bearer networks, first according to the information in the message The carried office direction information searches for the configuration information of the corresponding IP bearer network, and then judges whether it is an internal bearer based on the configuration information.

Described step E comprises:

E1) If a new TDM internal endpoint is added, search in the internal endpoint information table according to the time slot information in the endpoint identifier, if this TDM endpoint exists in the information table, then consider that the partner endpoint exists, otherwise consider that the partner endpoint does not exist;

E2) When a new IP internal endpoint is added, if IPBCP is used to establish the bearer, if the received command is to prepare for bearer, the return partner endpoint does not exist, and the local IP endpoint information is inserted into the internal endpoint information table; if the received The command is to establish a bearer. After the IPBCP negotiation is completed, obtain the IP address and port number information of the partner endpoint, search the internal endpoint information table, and obtain the context of the partner endpoint; if the MGC notifies the peer end of the IP address and port number through the change command, if If the received command is ready to carry, it will return that the partner endpoint does not exist, and insert the local IP endpoint information into the internal endpoint information table; when receiving the change command to notify the internal Number to find the internal endpoint information table to obtain the partner endpoint context;

E3) If the newly added endpoint is an ATM internal endpoint, search for the partner endpoint in the internal endpoint information table according to the bearer network identifier, and return the partner endpoint information if found.

The context association of the two internal endpoints includes:

If only one internal endpoint has a context allocated, and the context identifiers of the two VMGWs do not conflict, then the newly added internal endpoint uses the context allocated by the partner endpoint;

If contexts are allocated in the two VMGWs, insert the two context identifiers into a context association information table inside the MGW, and combine the contents of the two contexts to form a context.

The corresponding processing of the internal endpoint includes modifying, event reporting, playing, deleting or auditing the internal endpoint.

Using the method of the invention can effectively solve the problem of internal direct mutual communication between VMGWs.

Description of drawings

Fig. 1 is a system structure diagram after the bearer and control functions are separated in the WCDMA system.

Fig. 2 is a schematic diagram of the process of implementing a call between two media gateways.

Fig. 3 is a basic model diagram of communication between two VMGWs in a physical MGW.

Fig. 4 is a schematic diagram of configuration of internal and external bearer resources of a physical MGW.

FIG. 5 is a flowchart of a method for realizing internal intercommunication between VMGWs according to the present invention.

Detailed ways

The present invention achieves the purpose of supporting VMGW intercommunication by changing the processing procedure of the call message by the MGW equipment. The following description is only a general procedure, applicable to all call flows between the MGC and the MGW.

The basic model of communication between MGWs is shown in Figure 3, where

Internal endpoint: refers to the endpoint used for internal intercommunication between VMGWs;

External endpoint: refers to the endpoint that a physical MGW embodies externally;

Internal endpoints T1 and T2 are mutual partner endpoints; external endpoints T3 and T4 are mutual partner endpoints.

In the following description, external refers to the outside of the physical MGW, and internal refers to the relationship between two VMGWs inside the physical MGW.

1. Configuration of internal intercommunication resources between VMGWs

The two VMGWs are independent MGW devices to the MGC Server, and intercommunication internal bearer resources, such as IP, ATM or TDM, need to be configured between the two VMGWs. These internal bearer resources have no actual use on the MGW except communication address resources. The physical link resource exists and does not need to carry out the actual communication process, the MGC Server can use the same configuration information or obtain the resource configuration of the MGW through the audit function of the Media Gateway Control Protocol (H.248/MGCP). Any one of IP, ATM, and TDM can be configured as an internal bearer resource between two VMGWs, as shown in FIG. 4 .

In order to meet service and application requirements, it is necessary to restrict internal bearer resources according to the configuration of external bearer resources.

(1) If all the external bearer resources are TDM bearers, then the internal bearer resources are also configured as TDM bearers; because if packet IP or ATM bearers are configured between two TDM bearers, it will cause complicated voice codec conversion and control.

(2) If at least one of the external bearer resources is an IP bearer or ATM bearer, and if the internal bearer is also configured as an IP or ATM bearer, causing a VMGW to be a packet bearer in both directions, the MGC needs to notify the MGW to add a packet IP Or indicate the office route information for an ATM endpoint.

(3) If the external bearer resources are all IP bearers or ATM bearers, it is not recommended to configure the internal bearers as TDM bearers; because in WCDMA applications, configuring the internal bearer resources as TDM bearers will affect the TrFO service. It will cause the conversion of codec or the complexity of control operation.

(4) In other cases, the internal bearer resource can be arbitrarily configured as IP/ATM/TDM, which needs to be specified in the configuration information on the MGW: office route information, VMGW corresponding to the bearer, etc.

The above configuration commands can be implemented in multiple ways, for example, the configuration command is:

AddRes VMGW1 IN IP

The first field is the command; the second field indicates which VMGW is to be configured; the third field indicates the direction, which can also be 1, 2, 3, etc.; the fourth field indicates that the bearer resource is IP.

2. Basic process of intercommunication

The method flow is shown in Figure 5, and the specific description is as follows:

(1) After the MGW receives the message from the MGC, it judges whether to operate on the internal endpoint. If it is not an operation on the internal endpoint, it returns after processing the normal message; if it operates on the internal endpoint, go to (2);

(2) Determine whether to increase the internal endpoint message, if not, perform other processing on the internal endpoint; if so, determine whether the partner endpoint has already existed in a certain context, if the partner endpoint does not exist, then add the endpoint message as normal and then process Insert this endpoint into the internal endpoint description table and return; if the partner endpoint exists, go to (3);

(3) The context association of internal partner endpoints is combined into one context; in this way, two external partner endpoints communicate directly through this context to achieve the purpose of internal intercommunication.

3. Determine the internal endpoint process

The VMGW internal intercommunication bearer configured on the MGC Sever and the MGW can be an IP/ATM/TDM bearer, and different bearers have different methods for judging whether they are operating on internal endpoints.

(1) TDM bearer

According to the configuration information of the TDM bearer time slot search, the TDM configuration information should indicate whether each time slot is an internal time slot.

(2) ATM bearer

Find the ATM bearer configuration information. If there is only one ATM bearer network, judge whether it is an internal bearer according to the configuration information of the ATM bearer network; if there are multiple ATM bearer networks, first search for the corresponding ATM bearer according to the office direction information carried in the message. The configuration information of the network, and then judge whether it is an internal bearer according to the configuration information. If so, the ATM endpoint allocated on this bearer is an internal endpoint, otherwise it is an external endpoint.

(3) IP bearer

Search IP bearer configuration information. If there is only one IP bearer network, judge whether it is an internal bearer according to the bearer network configuration information; if there are multiple ATM bearer networks, first search for the corresponding ATM bearer according to the office direction information carried in the add endpoint message. Network configuration information, and then judge whether it is an internal bearer according to the configuration information. If yes, the IP endpoint allocated on this bearer is an internal endpoint, otherwise it is an external endpoint.

4. Query partner endpoint process

The internal bearer can be ATM/IP/TDM three bearers, and the process of querying the partner endpoint is different for different bearers.

(1) TDM endpoint

When a new TDM endpoint is added, the TDM endpoint identifier implicitly contains TDM time slot information. According to the consistent nature of the time slots at both ends during TDM intercommunication, the internal endpoint information table is searched. If this TDM endpoint exists in the information table, it is considered another An endpoint information has been added to the context, from which the context information can be obtained, and this endpoint is also added to the internal endpoint information table;

If more than one same TDM endpoint exists in the table, an error message will be prompted and a failure message will be returned.

(2) IP endpoints

There are two processes for establishing the IP bearer: using IPBCP to establish the bearer and MGC Server notifying the peer of the IP address and port number information through the change command.

I. If IPBCP is used to set up the bearer, when the command received by VMGW is ready to carry, the partner endpoint has not been added at this time, insert the local IP endpoint information into the internal endpoint information table, and return the partner endpoint does not exist; when VMGW receives The command is to establish a bearer. After the IPBCP negotiation is completed, obtain information such as the IP address and port number of the partner endpoint, search the internal endpoint information table, obtain the context of the partner endpoint, and return;

II. If the MGC Server notifies the peer IP address and port number through the change command, VMGW inserts the endpoint information into the internal endpoint information table when it receives the ready-to-carry addition endpoint. If there is no partner endpoint information, it returns that the partner endpoint does not exist; When the change command notifies the internal endpoint's IP address and other information, it searches the internal endpoint information table according to the peer IP address and other information, obtains the partner endpoint information, and returns.

(3) ATM endpoint

Judging the internal ATM endpoint can only be performed when the ATM endpoint is added in the process of establishing the bearer. When the ATM endpoint is added in the process of preparing the bearer, another ATM endpoint has not been added, and the endpoint information only needs to be inserted into the internal endpoint information table.

After the MGW receives the command to establish an ATM bearer, if it is an internal endpoint, it does not need to perform Q.AAL2 bearer negotiation, and searches the partner endpoint information in the internal endpoint information table according to the bearer network identifier. If the search is successful, it returns the partner endpoint information, otherwise it returns an exception.

5. Context association process

When two internal partner endpoints and their context information have been identified, the two contexts are associated.

(1) If only one of the two internal endpoints has a context allocated, and the context identifiers of the two VMGWs do not conflict, the newly added internal endpoint uses the context allocated by the partner endpoint, that is, the context content is merged;

(2) If the contexts are allocated separately in the two VMGWs, it is reflected as two contexts externally, and the two context identifiers are inserted into the context association information table inside the MGW, and the contents of the two contexts are merged. In fact, only one context exists;

(3) The content of the merged context includes all the information of the original two contexts, that is, the information related to the internal endpoints is also included in the context. The MGC Server cannot see the merging process, and can perform various operations on the two internal endpoints. ;

(4) When the bearer information is forwarded inside the MGW, only the merged context is used, that is, the bearer information is directly forwarded between two external endpoints without processing by the internal endpoints, so as to achieve the purpose of internal intercommunication.

6. Processing method after context association

After the context is merged, MGC Server can also perform operations on internal endpoints, including modification, event reporting, playback, deletion, auditing, etc. Some operations on internal endpoints, such as events and signals, can be directly operated on the external endpoints corresponding to the internal endpoints in the context. After removing the inner endpoint, the two contexts regain their independent relationship.

The present invention provides a method for internal intercommunication between VMGWs in the same physical MGW, effectively reducing resource consumption and communication delay between two VMGWs, and increasing the flexibility of VMGW use.

Claims (8)

1. A method for intercommunication between virtual media gateways (VMGWs), realizing internal intercommunication between VMGWs inside the same physical media gateway (MGW), comprising the following steps: A) Configuring internal bearer resources for intercommunication between VMGWs in the MGW; B) the media gateway controller (MGC) obtains the above configuration information; C) The MGW judges whether the operation is performed on the internal endpoint according to the configuration information and the message issued by the MGC, and if not, returns a response message after processing the normal message; if yes, proceeds to step D; D) judging whether to add an internal endpoint, if not, then return the response message after the internal endpoint is processed according to the normal operation process; if yes, then proceed to step E; E) Judging whether the partner endpoint exists, if not, then increase the endpoint message processing normally, insert the endpoint information into an internal endpoint information table, and return a response message; if yes, associate and merge the contexts of the two internal endpoints Create a context, through which external endpoints communicate directly during voice or data forwarding, and then return a response message. 2. The method for intercommunication among virtual media gateways (VMGW) according to claim 1, characterized in that: the internal bearer resource can be IP bearer, ATM bearer or TDM bearer. 3. The method for intercommunication between virtual media gateways (VMGW) according to claim 1, characterized in that: said step B can be configured by configuring internal bearer resources consistent with the MGW on the MGC or by auditing the media gateway control protocol The function is realized by obtaining the resource configuration of the MGW. 4. The method for intercommunication between virtual media gateways (VMGW) according to claim 1, characterized in that: said step C determines whether the operation is performed on an internal endpoint, including: C1) According to the TDM bearer time slot search configuration information on the MGW to judge; C2) according to the configuration information that ATM bears the weight of, judge whether internal bearer, if so, then the ATM end point that distributes on this bearer is exactly internal end point, otherwise is external end point; C3) According to the configuration information of the IP bearer, it is judged whether it is an internal bearer, if yes, the IP endpoint allocated on this bearer is an internal endpoint, otherwise it is an external endpoint. 5. The method for intercommunication between virtual media gateways (VMGW) as claimed in claim 4, characterized in that: in said step C2, if there is only one ATM bearer network, then judge according to the configuration of this ATM bearer network; if There are a plurality of ATM bearer networks, then at first search the configuration information of the corresponding ATM bearer network according to the office direction information carried in the message, and then judge whether it is an internal bearer according to the configuration information; in the step C3, if there is only one IP bearer network , judge according to the configuration of the IP bearer network; if there are multiple IP bearer networks, first search for the configuration information of the corresponding IP bearer network according to the office direction information carried in the message, and then judge whether it is an internal bearer network according to the configuration information . 6. The method for intercommunication between virtual media gateways (VMGW) according to claim 1, characterized in that: said step E comprises: E1) If a new TDM internal endpoint is added, search in the internal endpoint information table according to the time slot information in the endpoint identifier, if this TDM endpoint exists in the information table, then consider that the partner endpoint exists, otherwise consider that the partner endpoint does not exist; E2) When a new IP internal endpoint is added, if IPBCP is used to establish the bearer, if the received command is to prepare for bearer, the return partner endpoint does not exist, and the local IP endpoint information is inserted into the internal endpoint information table; if the received The command is to establish a bearer. After the IPBCP negotiation is completed, obtain the IP address and port number information of the partner endpoint, search the internal endpoint information table, and obtain the context of the partner endpoint; if the MGC notifies the peer end of the IP address and port number through the change command, if If the received command is ready to carry, it will return that the partner endpoint does not exist, and insert the local IP endpoint information into the internal endpoint information table; when receiving the change command to notify the internal Number to find the internal endpoint information table to obtain the partner endpoint context; E3) If the newly added endpoint is an ATM internal endpoint, search for the partner endpoint in the internal endpoint information table according to the bearer network identifier, and return the partner endpoint information if found. 7. The method for intercommunication between virtual media gateways (VMGW) according to claim 1, characterized in that: the context association of the two internal endpoints includes: If only one internal endpoint has a context allocated, and the context identifiers of the two VMGWs do not conflict, then the newly added internal endpoint uses the context allocated by the partner endpoint; If contexts are allocated in the two VMGWs, insert the two context identifiers into a context association information table inside the MGW, and combine the contents of the two contexts to form a context. 8. The method for intercommunication between virtual media gateways (VMGW) according to claim 1, characterized in that: said corresponding processing of internal endpoints includes modifying internal endpoints, reporting events, playing announcements, deleting or auditing operations .

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