WO2009030143A1

WO2009030143A1 - Multicast routing method and system, media gateway and media gateway controller

Info

Publication number: WO2009030143A1
Application number: PCT/CN2008/072114
Authority: WO
Inventors: Ning Zhu
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2007-09-03
Filing date: 2008-08-22
Publication date: 2009-03-12
Also published as: CN101383757A; CN101383757B

Abstract

A multicast routing method is provided, which includes: a trigger information for triggering multicast group members to change status on a downstream interface is obtained from the downstream interface of a media gateway, the trigger information includes the first multicast group information; if the status changing of the multicast group member on the downstream interface causes the record of the device multicast members database to change, an upstream interface of the media gateway corresponding to the second multicast group information in the changed record is searched according to the corresponding relationship between the multicast group information and the upstream interface; the first information is constructed according to the changed record of the device multicasting members database, the first information includes the third multicast group information; the first information is transmitted to a upstream network corresponding to the upstream interface through the upstream interface. A media gateway, a media gateway controller, a multicast routing system, a computer program product and a computer readable storage medium could execute the above multicast routing method. And the multicast may process between the different networks by using the method.

Description

Multicast routing method and system, media gateway and media gateway controller The application is submitted to the Chinese Patent Office on September 3, 2007, and the application number is 200710148050.4, and the invention name is "multicast routing method, device and system, media gateway and The priority of the Chinese Patent Application for the Media Gateway Controller is hereby incorporated by reference in its entirety. Technical field

The present invention relates to network technologies, and in particular, to a multicast routing method and system, a media gateway, and a media gateway controller.

Background technique

Multicast is a host communication method widely used in the network. Through multicast, packets can be sent to a certain set of network nodes in the network. The set of network nodes is called a multicast group. Group ). The basic idea of multicast is as follows: The source host sends only one piece of data. The destination address in this data is the multicast group address; all recipients in the multicast group can receive the same copy of the data, and only the group The host in the broadcast group can receive the data, and other hosts in the network cannot receive it. In an Internet Protocol (IP) network, multicast groups are identified by a Class D IP address (224.0.0.0 ~ 239.255.255.255).

The multicast technology covers a wide range of content, such as address allocation, group member management, multicast packet forwarding, and route establishment. According to the scope of the multicast protocol, the multicast protocol can be divided into host-router protocols. The multicast member management protocol, and the protocol between the router and the router, that is, the multicast routing protocol. Among them, the multicast member management protocol has an Internet Group Management Protocol (IGMP) applied to the IPV4 network, a Multicast Listener Discovery Protocol (MLD) applied to the IPV6 network, and the like; the multicast routing protocol is further divided into an intra-domain multicast routing protocol. And inter-domain multicast routing protocols. Intra-domain multicast routing protocols include protocols such as sparse mode independent multicast protocol (PIM-SM), dense mode independent multicast protocol (PIM-DM), and distance vector multicast routing protocol (DVMRP). Inter-domain multicast routing protocols include Multi-Protocol Border Gateway Protocol (MBGP), Multicast Source Discovery Protocol (MSDP) and other protocols.

Multicast routing can be divided into two categories: source tree and shared tree. A source tree is a forwarding tree formed by combining a multicast source as a root and a shortest path from a multicast source to each receiver. Since the source tree uses the shortest path from the multicast source to the receiver, it is also called the shortest path tree (SPT). For a group, the network establishes a tree for any multicast source that sends messages to the group. The shared tree uses a router as the root of the routing tree. The router is called a Rendezvous Point (RP: Rendezvous Point), which combines the shortest path of the RP to all receivers to form a forwarding tree. When using a shared tree, there is only one tree in the network for a certain group. All multicast sources and receivers use this tree to send and receive packets. The multicast source sends data packets to the root of the tree, and then the packets are forwarded down to all receivers.

With the development of multicast technology, the application of multicast technology is more and more extensive. However, when multicast technology is applied to communication between different networks, the IP network is taken as an example. If different IP networks correspond to different IP addresses. Versions, for example, IP networks corresponding to IPV4 and IPV6 respectively; or IP versions are the same, but the address ranges are partially or completely overlapping; or different IP networks have different plans for multicast group address planning and multicast source addresses; A normal router cannot complete multicast member management protocol messages, or multicast routing protocol messages, or multicast data flows between different IP networks; especially when using a media gateway (MGW: Media Gateway) as a border gateway. Because the existing MGW does not have the ability to process multicast member management protocol messages such as IGMP, MLD, and multicast routing protocol messages such as PIM-SM, when there are MGWs in the multicast path, IGMP, MLD, and so on. Broadcast member management protocol messages or multicast routing protocol messages such as PIM-SM and multicast data streams will be blocked by the MGW, resulting in It can not be broadcast between different networks, reducing the range of multicast applications.

Summary of the invention

The technical problem to be solved by the embodiments of the present invention is to provide a multicast routing method and system, a media gateway, and a media gateway controller. The technical solution provided by the embodiment of the present invention enables multicast to be performed between different networks.

The embodiment of the invention provides a multicast routing method, including:

And obtaining, by the downstream flow interface of the media gateway, trigger information that triggers a change of the state of the multicast group member on the downstream flow interface, where the trigger information includes the first multicast group information;

If the status of the multicast group member on the downstream flow interface is changed, the record of the multicast group member of the device is changed, and the information is obtained according to the first multicast group information and the correspondence between the multicast group information and the upstream flow interface. The upstream flow interface of the media gateway, the upstream flow interface is corresponding to the second multicast group information in the changed record, and the device multicast member database summarizes the status of the downstream flow interface multicast group member, The second multicast group information corresponds to the first multicast group information;

Constructing a first message according to the changed record in the device multicast member database, the first message And including the third multicast group information, where the third multicast group information is corresponding to the second multicast group information, and sending, by using the found upstream flow interface, the first network to the upstream network corresponding to the upstream flow interface. Message.

The embodiment of the invention further provides a media gateway, including:

The trigger information acquiring unit is configured to obtain, from the downstream flow interface, trigger information that triggers a change of the state of the multicast group member on the downstream flow interface, where the trigger information includes the first multicast group information;

a control information request sending unit, configured to send a control information request message to the media gateway controller, where the control information request includes the first multicast group information;

a control information receiving unit, configured to receive a control message from the media gateway controller in response to the control information request message;

The database judging unit is configured to determine whether the change of the state of the multicast group member on the downstream flow interface causes the record of the multicast member database of the device to be changed, and the device multicast group member database summarizes all the members of the downstream flow interface multicast group. State

An interface determining unit, configured to: when the database determining unit determines that the change of the state of the multicast group member on the downstream flow interface causes the record of the multicast member database of the device to change, according to the correspondence between the multicast group information and the upstream flow interface Relationship, searching for an upstream flow interface corresponding to the second multicast group information in the changed record in the multicast member database of the device;

a message sending unit, configured to: after the first message is configured according to the record changed in the multicast member database of the device, send, by using the upstream flow interface, the information including the multicast group information to the upstream network corresponding to the upstream flow interface a message, the first message includes third multicast group information corresponding to the second multicast group information.

The embodiment of the invention further provides a media gateway controller, including:

a control information request receiving unit, configured to receive a control information request message from the media gateway, where the control information request message includes first multicast group information;

a determining unit, configured to determine, according to the self-policy and the first multicast group information, whether to allow to join the multicast group;

The control information sending unit is configured to: when the determining unit determines that the multicast group is allowed to join the multicast group, send a control message that is allowed to join the multicast group, or send the multicast group not allowed when the determining unit determines that the multicast group is not allowed to join the multicast group. Control message. The embodiment of the invention further provides a multicast routing system, including:

The media gateway is configured to obtain, from the downstream flow interface, trigger information that triggers a change of a state of the multicast group member on the downstream flow interface, where the trigger information includes the first multicast group information, and sends a control information request to the media gateway controller. And receiving a control message that is allowed to join the multicast group in response to the control information request message; if the status of the multicast group member on the downstream flow interface is changed, the device multicasts that summarize the state of all the downstream flow interface multicast group members are received. The record of the member database is changed, and the upstream flow interface corresponding to the second multicast group information in the record changed in the multicast member database of the device is searched according to the correspondence between the multicast group information and the upstream flow interface; After the first message is configured, the first message is sent by the upstream flow interface, where the first message includes third multicast group information corresponding to the second multicast group information.

The media gateway controller is configured to receive the control information request message, determine, according to the first multicast group information, whether to allow to join the multicast group, and send the control that is allowed to join the multicast group when determining to allow the joining of the multicast group. Message

The first network is configured to receive the first message.

Embodiments of the present invention also provide a computer program product, the computer program product comprising computer program code, when the computer program code is executed by a computer, the computer program code may cause the computer to execute a multicast routing method Any of the steps in .

A further embodiment of the present invention also provides a computer readable storage medium, the computer storing computer program code, the computer program code, when the computer program code is executed by a computer, the computer program code to cause the computer to perform multicast routing Any of the steps in the method.

It can be seen from the foregoing technical solutions provided by the embodiments of the present invention that, when the state of the multicast group member on the downstream flow interface is changed, and the device multicast member database is changed, the multicast group can be learned. Corresponding relationship between the information and the upstream interface (upstream interface) determines the corresponding upstream flow interface, and the first message is sent through the upstream flow interface, so that the upstream flow network corresponding to the upstream flow interface corresponds to the downstream flow interface (downstream interface). The multicast of the downstream network is connected, so that multicast can be performed between two different networks, so that the application range of multicast is wider. DRAWINGS

1 is a flowchart of Embodiment 1 of a multicast routing method according to an embodiment of the present invention;

2 is a schematic diagram of Embodiment 2 of a multicast routing method according to an embodiment of the present invention; FIG. 3 is a schematic diagram of Embodiment 3 of a multicast routing method according to an embodiment of the present disclosure;

4 is a schematic diagram of Embodiment 4 of a multicast routing method according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of Embodiment 5 of a multicast routing method according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of Embodiment 6 of a multicast routing method according to an embodiment of the present disclosure;

FIG. 7 is a schematic diagram of Embodiment 7 of a multicast routing method according to an embodiment of the present disclosure;

FIG. 8 is a schematic diagram of Embodiment 8 of a multicast routing method according to an embodiment of the present disclosure;

FIG. 9 is a schematic diagram of Embodiment 9 of a multicast routing method according to an embodiment of the present disclosure;

FIG. 10 is a schematic diagram of forwarding a multicast data stream according to an embodiment of the present invention;

FIG. 11 is a structural diagram of an embodiment of a multicast routing apparatus according to an embodiment of the present invention;

FIG. 12 is a structural diagram of an embodiment of a media gateway according to an embodiment of the present invention;

13 is a structural diagram of an embodiment of a media gateway controller according to an embodiment of the present invention;

FIG. 14 is a structural diagram of Embodiment 1 of a multicast routing system according to an embodiment of the present invention;

FIG. 15 is a structural diagram of Embodiment 2 of a multicast routing system according to an embodiment of the present invention.

detailed description

The present invention will be further described in detail below with reference to the drawings and embodiments.

The multicast routing tree can be used to establish a multicast shared tree or a source tree. For a specific multicast group, the interface to the source of the multicast tree is called the upstream interface and the upstream interface is connected. The network is called the upstream network. In the direction of the multicast user, the interface away from the root node of the multicast tree is called the downstream interface, and the network connected to the downstream flow interface is called the downstream network. The multicast tree may be a source tree or a shared tree. The multicast group may not filter the multicast source address, or may have a filtering condition to limit the multicast source address, for example, including a multicast source address list, indicating that the multicast source address list can be received from the multicast source address list. The multicast data stream of the multicast source address; or the exclusion or exclusion of the multicast source address list, indicating that the multicast data stream of the multicast source address in the multicast source address list is not received. The multicast member management protocol and the multicast routing protocol can be run on the upstream and downstream flow interfaces. The multicast protocol for a multicast group (with or without a qualified multicast source address) may include the following four working modes. (1) The upstream flow interface uses the multicast member management protocol, and the downstream flow interface uses the multicast routing protocol; (2) the upstream flow interface uses the multicast member management protocol, and the downstream flow interface uses the multicast member management protocol; (3) upstream The flow interface uses a multicast routing protocol, and the downstream flow interface enables Multicast routing protocol; (4) The upstream flow interface enables the multicast routing protocol, and the downstream flow interface uses the multicast member management protocol. When the multicast member management protocol is used on the upstream interface, the device is equivalent to implementing the host function on the upstream network and can join or leave the multicast group. In other cases, the device implements router functions on the interface. It should be noted that the host function and the router function described herein are for a specific upstream stream interface and a downstream stream interface, and the upstream stream interface and the downstream stream interface may be for all multicast groups, or may only be for a part. Multicast group. That is, for a multicast group, an interface may be an upstream flow interface, and for another multicast group, the interface may be a downstream flow interface. It is also possible for a multicast source address of a multicast group address, an interface is an upstream flow interface, and another multicast source address of the multicast group address, the interface is a downstream flow interface.

The first embodiment of the multicast member management and multicast group routing method provided by the present invention is as shown in FIG. 1 , and includes:

Step 101: Acquire, from the downstream flow interface, trigger information that triggers a change of the state of the multicast group member on the downstream flow interface, where the trigger information includes the first multicast group information.

The trigger information may include any one of a message that joins the multicast group, a message that leaves the multicast group, a message that joins the multicast group and the outgoing multicast group, a response message of the query message, and a multicast timer timeout or The message requesting to join the multicast group may be an IGMP report message or a join/prune message of the PIM-SM. The message requesting to leave the multicast group may be an IGMPv3 report message, and the IGMPv2 leaving the multicast group message. Or PIM-SM join/prune messages, etc. A message requesting to join a multicast group and requesting to leave a multicast group means that a message includes a request to join a multicast group and a request to leave a multicast group, such as a report message of IGMPv3. Query messages are mainly used for multicast member management protocols, such as IGMP.

The multicast group information can include the multicast group address, the multicast group address and the multicast source address, or the multicast group address, the multicast source address, and the multicast source address filtering condition. The multicast source address filtering condition refers to the permission or A specific multicast source address, such as the filtering condition of the multicast source address of IGMPv3, is forbidden. The join/prune messages of the PIM-SM list the source address list and the source address list of the prune respectively. IGMPv2 does not support filtering of multicast source addresses. If the IGMP protocol is used on the downstream flow interface, the first multicast group information is carried in the IGMP report message or the leave message. If the PIM-SM protocol is used on the downstream flow interface, the first multicast group information is in the PIM- Carry in the SM join/prune message; The trigger information on the downstream flow interface includes the received multicast protocol message, such as a multicast member management protocol message or a multicast routing protocol message, and includes a timeout of the multicast timer and a response of the multicast query message, and the trigger information may be The status of the multicast group member on the downstream flow interface is changed, which may affect the record of the multicast member database of the device. Therefore, you need to send a message to the upstream flow interface to notify the upstream multicast router.

Step 102: If the status of the multicast group member on the downstream flow interface is changed, the record of the multicast member database of the multicast group member status of all the downstream flow interface members is changed, and the correspondence between the multicast group information and the upstream flow interface is changed. Finding an upstream flow interface corresponding to the second multicast group information in the record in which the change occurs;

The mapping between the multicast group information and the upstream flow interface is recorded in the correspondence table, and the corresponding upstream flow interface can be determined according to the multicast group information; The table can be pre-configured and can be updated in real time;

Step 103: Construct a first message according to the changed record in the multicast member database of the device, and send a first message to the upstream network corresponding to the upstream flow interface by using the found upstream flow interface.

The first message includes the third multicast group information corresponding to the first multicast group information. Generally, the information of the third multicast group information and the corresponding part of the first multicast group information are the same, but When the network address between the upstream network and the downstream network has a mapping relationship, the third multicast group information is obtained by updating the network address according to the mapping relationship between the first multicast group information and the network address; if the first message is a multicast member The management protocol, the DR in the upstream network processes the message, and if it needs to further send the join/prune message of the multicast routing protocol message to the root node of the multicast tree. If the first message is a multicast routing protocol message, the message is sent to the upstream multicast router of the multicast tree.

The embodiments of the present invention map multicast group addresses and/or multicast source addresses between different IP networks, and connect through network devices. For example, the multicast group G1 in the connected network 1 is planned to be mapped to G2 in the network 2, and the multicast source address S1 in the network 1 is planned to be mapped to the S2 in the network 2; the network 1 and the network 2 may be the same version. The IP network may also be a different version of the IP network, for example, the network is an IPv4 network, and the network 2 is an IPv6 network. If the multicast provided by the network 1 is requested in the network 2, and the multicast group address and/or the multicast source address are planned differently, the multicast group address and/or the multicast source address between the two networks must be performed. Mapping. Multicast routing protocol messages, multicast member management protocol messages, and multicast traffic flows across network ones and two networks, multicast group addresses and/or multicasts The source address should be updated accordingly according to the mapping relationship. The multicast routing protocol message, the multicast member management protocol message, and the multicast data stream use the same address mapping relationship to implement multicast protocol message control on the multicast data stream.

The multicast group address and the multicast source address in the multicast group information carried in the first message may be the same as the multicast group address and the multicast source address in the multicast group information included in the trigger information obtained by the downstream flow interface. It can also be a mapped multicast group address and a multicast source address.

After the state of the multicast group member on the downstream flow interface is changed, and the device multicast member database is changed, the corresponding upstream flow interface can be determined, and the message requesting to join and/or leave the multicast group is reconstructed. Sending through the upstream flow interface, so that the multicasts in the two networks are connected, so that multicast can be performed between two different networks, so that the application range of multicast is wider.

In actual applications, depending on the application scope of the multicast or the application domain, you may need to authenticate the host that requests to join the multicast group, or control the total number of hosts that join the multicast group, or The number of hosts that the network joins the multicast group is controlled. In this case, the host needs to be authenticated by the host. In general, the host is determined based on the address of the host. Judging the situation, such as using the unique number of the host in this network or the host name unique to the host in the entire network.

The multicast routing method provided by the embodiment of the present invention is described by using the IGMP protocol in the multicast member management protocol and the PIM-SM protocol in the multicast routing protocol, and the process is used when other multicast member management protocols and multicast routing protocols are used. similar.

(1) Receive a message joining the multicast group and leaving the multicast group on the downstream flow interface.

For the multicast member management protocol, the host on the downstream network sends a message requesting to join the multicast group and leave the multicast group. For example, the IGMPv2 protocol uses a report message to join a multicast group and a leave message to exit the multicast group. IGMPv3 unifies the above two messages into report messages by setting the filter conditions. The MLD protocol is similar to the IGMP protocol. The device of the present invention implements the function specified by the multicast member management protocol for the multicast router on the downstream flow interface, and maintains various multicast timers, such as a periodic query timer, a last member query interval timer, etc., and can also issue a periodic query. Messages and specific multicast group query messages. The device of the present invention can maintain the state of the multicast group member on the downstream flow interface, according to the state of the timer, whether the timer expires, the response message of the query message, and the message that is actively reported. The status of the multicast group member on the downstream flow interface is summarized by the downstream flow interface. The joining of the multicast group of the downstream network, including the multicast group joining of the hosts in the downstream network, and the joining of the multicast groups of the downstream multicast routers in the multicast tree in the downstream network, and these groups The multicast join situation of the broadcast router represents the multicast group join of these multicast routers in the entire downstream branch of the multicast tree.

For a multicast routing protocol, such as the PIM-SM protocol, the multicast router of the downstream network sends a join/prune message to request to join or leave the multicast group. Different from the multicast member management protocol, the PIM-SM protocol on the downstream network does not query the downstream network. The multicast router in the downstream network periodically refreshes the multicast group member status of the downstream branch of the multicast tree it represents. The pruning request is received on the interface and the pruning suppression timer is used to determine if pruning is required. The device can maintain the multicast group member status of the downstream network based on the received join/prune messages and the status of the multicast timer.

(2) Sending a message to join the multicast group and leave the multicast group on the upstream flow interface.

For the multicast member management protocol, the device performs the host function on the upstream flow interface, sends a report message or leaves the message, and responds to the query message. This part of the function is the basic function of the IGMP protocol and will not be described here.

For a multicast routing protocol, such as the PIM-SM protocol, the upstream flow interface requests to join the multicast group or leave the multicast group by issuing an add/prune message. In addition, a join/prune message is sent periodically to maintain the multicast group member status on the upstream multicast router. If a pruning request is received, a join/prune message is sent to veto if necessary. This part of the function is the basic function of the PIM-SM protocol, and will not be described here.

For the upstream flow interface, whether it is a multicast member management protocol or a multicast routing protocol, it is a summary of the multicast group member status of all downstream flow interfaces, and the summary records the device level for the upstream flow interface. Information about the multicast group member status, which is referred to herein as the device multicast member database. If all the multicast groups share the same upstream flow interface, the multicast member database of the device is used for the upstream flow interface, which reflects the joining of all downstream networks to the multicast group. If different multicast group addresses have different upstream flow interfaces, or different multicast source addresses of the same multicast group address have different upstream flow interfaces, the device multicast member database must correspond to different upstream flow interfaces. The multicast group address, or the multicast group address and the multicast source address, summarizes the aggregation of the multicast group member status of the multicast group address of each downstream flow interface. May lead to the source tree for the same multicast group address The upstream stream interface is different from the upstream stream interface to the shared tree. If the same multicast data stream is requested to have both a source tree and a shared tree, the device may also need to select the upstream stream according to the selection of the multicast tree. interface.

The four possible working modes of the upstream and downstream flow interfaces using the multicast protocol may work separately or in several ways. For example: Downstream flow interface may receive downstream of the downstream flow interface connection. The multicast member management protocol message sent by the host or router in the network to join the multicast group may also receive the multicast routing protocol message sent by the multicast router in the downstream network to join the same multicast group. The multicast group member status on the flow interface needs to be combined with the trigger information caused by the two protocols. Sending a message to the upstream stream interface can use either the multicast member management protocol or the multicast routing protocol.

The possible conditions for all multicast source addresses of a multicast group to share the same upstream flow interface: The interface faces the shared tree in the direction of all multicast groups.

A possible situation of multiple upstream flow interfaces: the shared tree of different multicast groups can be reached through different upstream flow interfaces, or the source tree root nodes of different multicast source addresses can pass different upstream flow interfaces. Arrivals.

Generally, if the status of multicast group members of all downstream flow interfaces does not change, the records of the device multicast member database will not change. If the change of the multicast group member status of one or more downstream flow interfaces affects the record of the device multicast member database and needs to be changed, further affecting one or more upstream flow interfaces, the device moves to the affected upstream flow interface. Send a message to reflect changes in the status of multicast group members at the device level. If it is an IGMP protocol, it may be a report message or leave message. If it is a PIM-SM protocol, it may be a join/prune message.

A multicast group request message on a downstream flow interface affects the possible conditions of multiple upstream flow interfaces: The downstream flow interface is required to join the multicast group G1. The multicast source address filtering conditions include only the multicast source addresses S1 and S2. . The upstream flow interface corresponding to the SI is II, and the upstream flow interface corresponding to S2 is 12. If the respective source tree is to be added to the upstream flow interface, this will cause the join group to be sent to the upstream network on both the II and the 12th. Broadcast group message.

The present invention can work in the case where the upstream network and the downstream network have the same multicast group address planning and multicast source address planning. If there is a multicast group address and/or a multicast source address mapping between the upstream network and the downstream network, the multicast protocol processing and multicast data stream forwarding on the device must use the address. Mapping so that the upstream and downstream stream interfaces can operate against the same multicast group. For example, if the downstream traffic interface receives the message from the multicast group G1, the multicast group member status on the interface needs to be updated. The upstream flow interface corresponding to G1 is 12. In the 12 connected upstream network, the group The broadcast group is planned to be the multicast group G2, and further determines whether the device multicast member database also needs to be updated. If it needs to be updated, the device sends a message requesting to join the multicast group G2 on the 12 interface. If the filtering condition of the multicast source address is involved in the request message, the mapping method of the multicast source address is similar to the mapping method of the multicast group address, and is not described here.

The above functions can be implemented on a separate network device, which can be an MGW; the MGW is controlled by a Media Gateway Controller (MGC). In one case, the above functions are implemented by the MGW. The MGC does not need to directly process the messages on the upstream stream interface and the downstream stream interface. In another case, some or all of the MGC controls the function. step. For example, the correspondence between the multicast group information and the upstream flow interface can be maintained by the MGC. After receiving the multicast protocol message on the downstream flow interface, the MGW reports the message to the MGC. The MGW instructs the MGW to send the specified multicast protocol message on the specified upstream flow interface. Therefore, the mapping between the multicast group information and the upstream flow interface is not required on the MGW.

The multicast group information includes multicast group address, multicast source address, and multicast group source address filtering. The multicast group information in the IGMPv2 message may include only the multicast group address. The multicast group information in the PIM-SM protocol message may include the multicast group address, and may further include the added multicast source address and the pruned The multicast source address of the IGMPv3 protocol message may include a multicast group address, and may further include a multicast source address and a filtering condition of the multicast source address. There are three possible scenarios for the correspondence between the multicast group information and the upstream flow interface: (1) the correspondence between the multicast group address and the upstream flow interface; (2) the multicast group address and one or more groups. The mapping between the source address and the upstream stream interface. The multicast group address is the specified multicast group address. The multicast source address is the mapping between the multicast source address and the upstream stream interface. (3) The correspondence between the multicast group address and the excluded one or more multicast source addresses and the upstream flow interface; that is, the multicast group address is the specified multicast group address, and the multicast source address is the specified group. All multicast source addresses except the source address. The multicast data stream described in the multicast group information is received from the corresponding upstream flow interface and sent to the downstream network through the downstream flow interface. The correspondence between the multicast group information and the upstream flow interface described in the embodiment of the present invention may include any one of the foregoing three possible cases or any combination thereof. After the device multicast member database is changed, the changed record contains the multicast group information. The upstream flow interface corresponding to the multicast group information is searched for, and the corresponding request is added according to the multicast group information in the changed record. A multicast group, a message leaving the multicast group, and then sent to the upstream stream interface that is found.

The MGW can maintain the correspondence between the multicast group information and the upstream flow interface. In this case,

The MGW can search for the upstream flow interface by using the multicast group information according to the foregoing correspondence, and can also maintain the multicast group address and/or the multicast source address mapping relationship network address mapping table between the upstream flow interface and the downstream flow interface; After receiving the multicast member management protocol message or the multicast routing protocol message, the MGW can update the multicast member status of the interface, further update the device multicast member database, find the corresponding upstream flow interface, and send the multicast member to the upstream flow interface. Management protocol messages or multicast routing protocol messages do not require the participation of the MGC. Of course, the MGC can also use the media gateway control protocol to update the correspondence between the network address mapping table and the multicast group information on the MGW and the upstream flow interface.

As shown in FIG. 2, the multicast routing method provided by the embodiment of the present invention is separately implemented by using a multicast routing device, which uses a multicast member management protocol on a downstream flow interface and a multicast routing protocol on an upstream flow interface. The second embodiment of the multicast routing method provided by the embodiment of the present invention specifically includes:

The multicast routing device uses the IGMP protocol as the multicast router in the IP network 2; receives the IGMP protocol-based advertisement message from the host in the IP network 2, leaves the multicast group message, and sends an inquiry message to the IP network 2;

The multicast routing device acts as a multicast router in the IP network 1 and uses the PIM-SM protocol; sends a PIM-SM based join/prune message to the multicast router in the IP network 1;

After receiving the multicast data stream from the multicast router in the IP network 1, the multicast routing device forwards the multicast data stream to the host in the IP network 2.

In a practical application, the mapping between the multicast group address and the multicast source address of the upstream network and the downstream network is configured on the multicast routing device, and the correspondence between the multicast group information and the upstream flow interface is also configured. The multicast member management protocol uses IGMPv3 as an example. The multicast routing protocol uses the PIM-SM protocol as an example. Run the IGMP protocol on the downstream traffic interface to maintain the multicast group member status on the downstream flow interface. If the member status changes, determine whether the device multicast member database needs to be changed. If necessary, send PIM on the upstream flow interface. SM protocol join/prune messages to represent device-level multicast group members Change of state. The upstream traffic interface runs the PIM-SM protocol. The join/prune message is sent to the upstream multicast router to update the multicast group member status and send join/prune messages for prune suppression. If there is a mapping between the multicast group address and/or the multicast source address, the mapped join address is used in the sent join/prune message.

After receiving the multicast data stream on the upstream flow interface, the multicast stream is distributed according to the state of the multicast member on each downstream flow interface. If a multicast group address and/or multicast source address mapping is required, the multicast group address and/or the multicast source address are modified to the mapped address according to the mapping relationship when the multicast stream is sent on the downstream stream interface. .

As shown in FIG. 3, the multicast routing method provided by the embodiment of the present invention is separately implemented by using a multicast routing device, which uses a multicast member management protocol on the downstream flow interface and multicast member management on the upstream flow interface. The third embodiment of the multicast routing method provided by the embodiment of the present invention specifically includes: The multicast routing device uses the IGMP protocol as the multicast router in the IP network 2; and receives the IGMP protocol based on the host in the IP network 2. The message, leaving the multicast group message, sending an inquiry message to the IP network 2, etc.;

The multicast routing device uses the IGMP protocol as the host in the IP network 1, sends the IGMP protocol-based report message to the multicast router in the IP network 1, leaves the multicast group message, and responds to the query message;

In a practical application, the multicast routing device configures a multicast group address of the upstream network and the downstream network.

The mapping between the multicast source address and the upstream source interface is also configured. The multicast member management protocol uses IGMPv3 as an example. Run the IGMP protocol on the downstream interface to maintain the status of the multicast group member on the downstream flow interface. If the status of the member changes, determine whether the multicast member database needs to be changed. If necessary, send IGMP on the upstream interface. Report messages to represent changes in the status of multicast group members at the device level. The upstream flow interface runs the IGMPv3 protocol and responds to the IGMP query messages of the upstream network according to the protocol. If there is a mapping between the multicast group address and/or the multicast source address, the mapped message is used in the sent report message.

After receiving the multicast data stream on the upstream flow interface, the multicast stream is distributed according to the multicast group member status on each downstream flow interface. If there is a mapping between multicast group address and/or multicast source address If the multicast stream is sent on the downstream flow interface, the multicast group address and/or the multicast source address are modified to the mapped address according to the mapping relationship.

As shown in FIG. 4, the multicast routing method provided by the embodiment of the present invention is implemented by using a multicast routing device. The multicast routing protocol is used on the downstream flow interface, and the multicast member management protocol is also used on the upstream flow interface. The fourth embodiment of the multicast routing method provided by the embodiment of the present invention specifically includes: the multicast routing device functions as a multicast router in the IP network 2, using the PIM-SM protocol; and receiving the PIM-based multicast router from the IP network 2 Join/pruning messages of the SM protocol, etc.;

After receiving the multicast data stream from the multicast router in the IP network 1, the multicast routing device forwards the multicast data stream to the multicast router in the IP network 2.

In the actual application, the mapping between the multicast group address and the multicast source address of the upstream network and the downstream network is configured on the multicast routing device, and the mapping between the multicast group information and the upstream flow interface is also configured. The multicast routing protocol uses the PIN-SM protocol as an example. The multicast member management protocol uses IGMPv3 as an example. Run the PIM-SM protocol on the downstream traffic interface to maintain the multicast group member status on the downstream flow interface. If the member status changes, determine whether the device multicast member database needs to be changed. If necessary, send it on the upstream flow interface. IGMP reports messages to represent changes in device-level multicast group membership status. The upstream flow interface runs the IGMPv3 protocol and responds to the IGMP query messages of the upstream network according to the protocol. If there is a mapping between a multicast group address and/or a multicast source address, the mapped address is used in the transmitted report message.

On the downstream flow interface, the multicast group member status is obtained through the multicast routing protocol. The downstream network and the more downstream network closer to the host user need to consider the upstream flow interface address when running the multicast routing protocol. The address of the upstream router on the multicast tree, the multicast tree does not bypass the downstream flow interface. A possible method is that the multicast routing device functions as an RP on the downstream flow interface. The downstream flow interface address is RP. The address, on the downstream flow interface, forwards the multicast data stream to the downstream branch of the shared tree, and simultaneously receives and processes the join/prune message sent by the downstream network.

As shown in FIG. 5, the multicast routing method provided by the embodiment of the present invention is separately implemented by using a multicast routing device. The multicast routing protocol is used on the downstream flow interface, and the multicast routing protocol is also used on the upstream flow interface. The fifth embodiment of the multicast routing method provided by the embodiment of the present invention specifically includes:

The multicast routing device acts as a multicast router in the IP network 2, and uses the PIM-SM protocol; receives the PIM-SM-based join/prune message from the multicast router in the IP network 2;

In the actual application, the mapping between the multicast group address and the multicast source address of the upstream network and the downstream network is configured on the multicast routing device, and the mapping between the multicast group information and the upstream flow interface is also configured. The multicast routing protocol uses the PIN-SM protocol as an example. Run the PIM-SM protocol on the downstream interface to maintain the multicast group member status on the downstream flow interface. If the member status changes, determine whether the device multicast member database needs to be changed. If necessary, send the multicast member interface. The IGMP report message represents the change in the state of the multicast group member at the device level. The upstream traffic interface runs the PIM-SM protocol. The join/prune message is sent to the upstream multicast router to refresh the multicast group membership status and the join/prune message is sent to perform pruning suppression. If there is a mapping between the multicast group address and/or the multicast source address, the mapped address is used in the sent join/prune message.

After receiving the multicast data stream on the upstream flow interface, the multicast stream is distributed according to the multicast group member status on each downstream flow interface. If a multicast group address and/or multicast source address mapping is required, when a multicast stream is sent on the downstream stream interface, the multicast group address and/or the multicast source address are mapped. The shot relationship is modified to the mapped address.

Among them, the four cases described in Figure 2, Figure 3, Figure 4 and Figure 5 can be implemented partially or completely on the same multicast routing device.

The multicast routing device described above may be an improved MGW. When the MGW is used, the MGW may be used to control the MGW, so that the MGW can implement the multicast routing method provided by the embodiment of the present invention, and use the MGC to perform the MGW on the MGW. During control, some extensions to the media gateway control protocol between the MGC and the MGW are required, which are described in detail below.

As shown in FIG. 6, the MGC controls the MGW to enable the MGW to implement the multicast routing method provided by the embodiment of the present invention. The downstream flow interface of the MGW uses the multicast member management protocol and is used on the upstream flow interface of the MGW. The multicast routing protocol, the sixth embodiment of the multicast routing method provided by the embodiment of the present invention specifically includes:

The MGW acts as a multicast router in the IP network 2, and uses the IGMP protocol; receives an IGMP-based message from the host in the IP network 2, leaves the multicast group message, and sends an inquiry message to the IP network 2;

The MGW functions as a multicast router in the IP network 1 and uses the PIM-SM protocol; sends a PIM-SM based join/prune message to the multicast router in the IP network 1;

After receiving the multicast data stream from the multicast router in the IP network 1, the MGW forwards the multicast data stream to the host in the IP network 2.

The MGW is controlled by the MGC when performing some or all of the above processes, and the MGC controls the MGW through the extended H.248 protocol.

On the IP network 2 side of the MGW, the MGC sets the H.248 event detection IGMP message to the MGW to join the multicast group. In the IGMP protocol, the message is a report message. For example, the event igmprl can be set to detect one or more of the IGMP Report (Membership Report) message, the Join/Leave Multicast Group message, and the Query (Member Query) message. The event has the following parameters: Parameter iprealm, its data The type is String list, and the default value is null; its value is a list of IP domains that detect IGMP messages. The value can refer to the realm attribute of the ipdc packet in the ITU-T H.248.41 standard.

If the event is set on the ROOT terminal of the MGW, the parameter can be used to indicate which IP domain or interface to detect the IGMP message. If the value of this parameter is null, it means that detection is performed on all IP domains or interfaces of the MGW. If the event is set on a non-ROOT terminal, And the terminal is created on an IP domain or interface, you do not need to set this parameter.

There is also a process of electing a querier in the IP network 2, and the MGW can assume the role of a querier. The MGC can signal to the MGW to send an IGMP query message. Part or all of the sending and receiving of the IGMP query message may be automatically performed by the MGW according to the logic of the IGMP protocol specification for sending the query message to reduce the number of message interactions between the MGC and the MGW. The MGW can also send periodic query messages according to the working principle of the querier itself. In order to meet the requirements of the IGMP protocol, the IGMP protocol specifies a large number of timers and parameters, such as group membership interval, Robustness Variable, Query Interval, etc. The duration of these timers and the values of the parameters can be The configuration on the MGW can also be set or updated by the MGC through the H.248 protocol.

After receiving the message that the group joins the multicast group, the MGW can determine whether it needs to update the multicast group member status on the downstream flow interface. If there are multiple downstream flow interfaces, you need to configure the multicast group members of the downstream flow interfaces. The status is merged. If there is a change in the multicast data flow request on the upstream flow interface, the PIM-SM protocol-based join/prune message is required to be sent to the upstream flow interface. The upstream interface (Upstream Interface) points to the direction of the root node of the shared tree or the source tree. Send and receive multicast routing protocol messages on this interface. The downstream stream interface (Downstream Interface) deviates from the root node and connects to the host to perform multicast member management.

The MGW may also report the received group report message or the leaving multicast group message to the MGC, and the MGC performs authentication according to the user subscription information, the resource status, and the like, and performs corresponding operations according to the authentication result, for example, instructing the MGW to perform upstream flow. The prune on the interface, or the MGC feeds back the received report message to the MGW. If the request to join the multicast group in the IGMP is rejected, the MGW is notified. The notification mode includes directly responding to the MGW report message error code or subsequent transmission. The message indicates the MGW, and the MGW rejects the request to join the multicast group. The MGW can send a join/prune message to the upstream network according to the change of the state of the multicast group member on each downstream flow interface.

Define H.248 event igmpreport, set this event on the specified interface or all interfaces. to

When the MGC reports the event, it can be, but is not limited to, carrying the following parameters:

(1) The parameter iprealm, the data type is String, the default value is null; its value is the IP field indication for detecting IGMP messages. The value can refer to the realm attribute of the ipdc packet in the ITU-T H.248.41 standard. In addition, the IP domain indications in the present invention can be replaced by interface names, which represent similar meanings. Thinking. If the event is set on a non-ROOT terminal and the terminal is created on an IP domain or interface, this parameter does not need to be reported.

(2) The parameter ver, the data type is integer, the default value is 3; its value is the protocol version, and 1, 2, 3 represent the IGMP versions 1, 2 and 3.

(3) Parameter type, the data type is integer, the default value is 1; its value represents the message type. For example, 1 can represent IGMP report message (join message), 2 for IGMP leave group message, and 3 for IGMP query message.

(4) The parameter rl, the data type is string list, the default value is null; its value represents the content of the report message. Each row in the list represents the content of the report for a group. For IGMP VI and IGMP V2, the content of each line is the group address of a multicast group. For IGMP V3, it is more complicated. The format of each line in the list is as follows:

Multicast group address, type, source address 1, source address 2,

Types can include the following:

MODE— IS— INCLUDE

MODE— IS— EXCLUDE

CHANGE— TO— INCLUDE— MODE

CHANGE— TO— EXCLUDE— MODE

ALLOW— NEW— SOURCES

BLOCK OLD SOURCES

If the line in the parameter rl string list is " 224.100.200.3 , 1 , 192.168.1.2 ,

192.168.1.3" means to join the multicast group 224.100.200.3, the source address filtering type is MODE-IS-INCLUDE, and the source address list is 192.168.1.2 and 192.168.1.3, that is, it is required to join the multicast group 224.100.200.3, but the limit is The multicast source address must be 192.168.1.2 or 192.168.1.3.

(5) The parameter lg, the data type is String list, and the default value is null; its value represents the list of outgoing multicast groups and multicast source addresses. Each item in the list is a multicast group address and a multicast source address. . The format is as follows:

Multicast group address, multicast source address 1 , ... multicast source address n

The multicast source address is optional. If it is not included, it indicates all multicast source addresses.

For example: "224.100.250.1" means that a member with a multicast group "224.100.250.1" left. "224.100.250.1, 202.114.100.100" indicates that the multicast source address "202.1140.25.100" of the multicast group "224.100.250.1" is left.

(6) The parameter sa, the data type is String, which is the source address of the received IGMP message. In an actual application, if the MGW sends a query message triggered by the MGC, the H.248 needs to be extended. For example, the extended H.248 signal igmpre is used by the MGC to instruct the MGW to send an IGMP query message, and the signal includes the following parameters:

(1) The parameter iprealm, the data type is String, the default value is null; its value is the IP domain list for sending IGMP messages. For the value, refer to the realm attribute of the ipdc packet in the ITU-T H.248.41 standard.

If the event is set on a non-ROOT terminal and the terminal is created on an IP domain or interface, this parameter does not need to be reported.

(3) The parameter mrc, the data type is integer, the default value is null; its value represents the Max Resp Code field in the query message. Indicates the maximum length of time to wait for a response report.

(4) The parameter ga, the data type is string, and the default value is null; its value represents the multicast group address in the query message.

(5) The parameter sal, the data type is string list, and the default value is null; its value represents the list of multicast source addresses in the query message.

After receiving the igmpre signal of the MGC, the MGW constructs and sends an IGMP query message according to the parameters in the signal.

In the IP network 1, the MGC instructs the MGW to receive the report and send the PIM-SM protocol message, so the H.248 protocol should be extended accordingly, and the signal can be defined in the existing or newly defined H.248 packet for the MGC indication. The MGW sends a PIM-SM protocol message. For example, the signal jp can be defined for the MGC to instruct the MGW to send a Join/Prune message, which includes one or more of the following parameters:

(1) The parameter iprealm, the data type is String, and the default value is null. The value is the IP field of the join/prune message sent by PIM-SM. The value can refer to the realm attribute of the ipdc packet in the ITU-T H.248.41 standard. This parameter can also be replaced by the interface name parameter, which has similar functions.

(2) The parameter uns (Upstream Neighbor Address), the data type is string; The value represents the address of the upstream neighbor. This value is encoded and populated into the corresponding field of the join pruning message.

(3) The parameter ht ( HoldTime ), the data type is integer, the value of this parameter indicates the length of time the receiver remains in the pruning state, in seconds. This field is populated in the corresponding field of the join pruning message.

(4) The parameter content, the data type is string list; each row in the list represents a join pruning request for a multicast group address (specified or wildcard). Each line is a string of the following format: "Group address m, join source number n, pruning source number k, join source address 1, ... join source address n, pruning source address 1, ... pruning source Address k";

For example: "224.225.250.1, 1 , 2 , 202.196.1.100 , 202.196.1.200 , 202.196.1.201 ", this line indicates that the multicast group "224.225.250.1" is added, and the source address "202.196.1.100" is added. Pruning the multicast group, pruning source addresses "202.196.1.200" and "202.196.1.201";

The multicast group address described above can specify a specific multicast group address or a wildcard format. Corresponds to the Multicast Group Address m field in the prune message. m is the line number of the parameter string list. The source IP address corresponds to the Joined Source Address field, and the pruning source address corresponds to the Pruned Source Address field. Both the source address and the prune source address support wildcards.

To complete the function of the complete PIM router, you need to implement the PIM Register Message, the Register-Stop Message and the PIM Assert Messages. The corresponding H.248 signals and events can also be extended, so that the MGC can signal the MGW to send the PIM message, and the MGW detects the received PIM message through the event and reports it to the MGC. The specific extension is similar to the previous H.248 protocol extension for join/prune, and will not be described here.

The multicast router sends a multicast data stream to the MGW. The MGW receives the multicast data stream and forwards the received multicast data stream to the downstream stream interface with the multicast group member according to the status of the multicast group member on each downstream flow interface. on. If the MGW performs multicast group address mapping and/or multicast source address mapping, the multicast group address and/or source address of the forwarded multicast data stream must be replaced accordingly to avoid multicast groups. The member host does not recognize the data stream. The mapping relationship may be configured on the MGW, and the MGC may further instruct the MGW to perform media stream forwarding and mapping relationship by using an H.248 protocol message. For example, the signal gdmap may be defined, and the signal has the following parameters: (1) The parameter daa, the parameter content is a list of newly added or updated multicast group address mapping relationships. The format of each line in the list is:

"Downstream IP domain indication, upstream IP domain indication, downstream multicast group address, upstream multicast group address mapped to";

For example "dl, d2, 224.200.251.1, 224.200.100.2," indicates that the IP domain "dl", the multicast group address "224.200.251.1" is mapped to the IP domain "d2," of "224.200.100.2"; The upstream multicast group address is optional. If the parameter does not contain this entry, the multicast group address mapping is not performed for the multicast group. This line only describes an upstream and downstream flow interface relationship of the multicast group. If there is multiple downstream flow interfaces on the upstream upstream interface of the multicast tree of the multicast group, the multiple lines of the parameter list are described.

(2) Parameter sda, the content of the parameter is a new or updated list of multicast source address mapping relationships. The format is: "downstream IP domain indication, upstream IP domain indication, downstream multicast group address, downstream multicast source address, upstream multicast source address mapped to"; "upstream multicast source address mapped" is optional. Without this item, it means that there is no need to map the source address. The line only describes an upstream and downstream flow interface relationship of the multicast source address corresponding to the multicast group. If an upstream flow interface of the multicast source address of the multicast group has multiple downstream flow interfaces, the parameter is adopted. A multi-line description of the list. For example: "dl, d2, 224.200.251.1, 192.168.1.100" means an IP network with a source address of "192.168.1.100" for multicast group "224.200.251.1" and an IP network with "d2" for IP domain It is the upstream network, and the IP network indicated by the IP domain as "dl" is the downstream network.

There may be more mapping entries, so you can also extend the package to support auditing. MGC knows how many mappings exist from the audit results, and audits the contents of the mapping in batches. If the MGW sends a join/prune message to the upstream network according to the change of the multicast group member status on each downstream flow interface, the MGW must also know the address mapping relationship, the multicast group address and multicast in the join/prune message. The data stream source address must be translated to the address of the mapped upstream network by the address in the request message on the downstream stream interface.

In addition to the above, the MGC controls the MGW to accept the report of the multicast member management protocol message on the downstream flow interface and instructs the MGW to send the multicast routing protocol message on the upstream flow interface, and another MGW relies on the configuration data to autonomously complete the foregoing multicast. The method of routing function. You need to configure support for multicast member management protocols and multicast routing protocols on the multicast routing device, and configure multicast groups and sources. The address and the upstream and downstream flow interface relationship and the upstream router address (the part can be configured to receive the PIM-SM "bootstrap, message"), the multicast group address mapping relationship, and the multicast source address mapping relationship. Or all. The configuration information may include the following items in part or in whole, but is not limited to the following:

(1) Interfaces that run IGMP, and configure which interfaces need to support IGMP messages.

(2) The interface that runs the PIM-SM protocol, and configures which interfaces need to support the sending and receiving of PIM-SM messages.

Both the IGMP protocol and the PIM-SM protocol can be run on the same interface. This example is based on IGMP and PIM-SM. In fact, the principles of the present invention can be applied to other multicast member management protocols and multicast routing protocols. Therefore, if multiple protocols are available, you need to configure them. The protocol type of the multicast member management protocol and multicast routing protocol used, such as MLD, PIM-DM, and so on.

(3) The IP address of the IGMP protocol running on the interface. This address is the local address for sending and receiving IGMP messages. An interface may have multiple addresses. In addition, the multicast routing device may have multiple interfaces connected to the same IP. Therefore, it is necessary to configure the IP address used by the IGMP protocol on an IP network.

(4) The IP address of the PIM-SM protocol running on the interface. This address is the local address of the PIM-SM message. An interface may have multiple addresses. In addition, the multicast routing device may have multiple interfaces connected to the same IP. Therefore, it is necessary to configure the IP address used by the PIM-SM protocol on an IP network.

(5) The address of the RP. Different multicast groups may have different RPs. The multicast routing device may also obtain the RP address used by each multicast group from the received PIM-SM bootstrap message. But sometimes it is not available, relying on configuration.

(6) The upstream router address of the interface; different multicast groups, or different multicast source addresses of the same multicast group, may have different upstream router addresses.

If the RP address or the multicast source address is obtained, the multicast routing device can obtain the address of the upstream router or the upstream router of the source tree through unicast routing, which is based on the RPF principle. However, if the multicast routing device may not be able to directly route with the RP or the like, the configuration method can also be implemented.

(7) The upstream flow interface corresponding to the multicast group address; the upstream flow interface of the shared tree of a multicast group. The multicast routing device sends a PIM-SM join/prune message of the multicast group to the upstream router through the interface.

(8) The upstream flow interface corresponding to the multicast group address and the multicast source address; the upstream flow interface of the source tree of a multicast source address of a multicast group. If the interface is the same as the upstream stream interface of the shared tree of the multicast group, it is not necessary to configure the source address separately. Therefore, it is better to configure the upstream stream interface of the source tree.

(9) The mapping relationship between the multicast group address mapping relationship and the multicast source address.

This mapping relationship is used not only for the mapping of addresses in multicast routing messages, but also for modifying the multicast group address and source address in the IP header when forwarding multicast data streams.

(10) User permission settings. Set the permissions of each user, including the range of multicast groups that can be joined. After receiving the IGMP request to join the multicast group, the multicast routing device may determine whether to discard the request message according to the permission configuration of the user. With the configuration of the present invention, the multicast routing device can forward the multicast data stream by itself.

(11) Configuration of various timers and parameters specified by IGMP and PIM-SM protocols.

If the multicast routing device is a media gateway, some or all of the above settings of the media gateway may also be set or updated by the media gateway controller.

Use the content of the signal gdmap to configure multicast group address mapping and multicast source address mapping between the networks where the upstream and downstream flow interfaces are located. In order to enable the media gateway controller to control the correspondence between the multicast group information on the media gateway and the upstream stream interface, the following parameters may be extended on the signal gdmap:

Parameter upa. The format is: "upstream multicast group address, upstream IP domain indication, filter condition, multicast source address 1, ... multicast source address n"; for example: "224.100.200.111, dl, include, 202.114.100.200,, The upstream flow interface of the multicast group whose multicast source address is "202.114.100.200" is in the IP domain "dl". For example: "224.100.200.111, dl, exclude, 202.114.100.100" indicates that the multicast group address is "224.100.200", and the upstream stream interface of the multicast group with all source addresses except "202.114.100.100" is in the IP domain "dl".

The H.248 protocol can be further extended to allow the MGC to instruct the MGW to modify other configurations. In addition, the signal gdmap can also carry the same configuration information by using the H.248 attribute, and the specific method is not described here. The two methods described above can be used in combination.

As shown in FIG. 7, the MGC controls the MGW to enable the MGW to implement the multicast routing method provided by the embodiment of the present invention. The downstream flow interface of the MGW uses the multicast member management protocol and is used on the upstream flow interface of the MGW. The multicast member management protocol, the seventh embodiment of the multicast routing method provided by the embodiment of the present invention specifically includes:

The MGW acts as a host in the IP network 1 and uses the IGMP protocol; sends an IGMP-based report message to the multicast router in the IP network 1, leaving the multicast group message and responding to the query message;

The multicast member management protocol is used on both the downstream flow interface and the downstream flow interface of the MGW. The processing on the downstream flow interface is the same as that in the case of the case 1, and the packets on the downstream flow interface are maintained by receiving the messages of the multicast group member and the outgoing multicast group that are processed by the multicast member management protocol. The status of the broadcast timer sends a query message to defend the status of multicast group members on the downstream flow interface. In addition, after the device multicast member database is maintained, the device multicast member database is changed, and the multicast member management protocol joins the multicast group and leaves the multicast group to send the message to the MGW as a host. Subscription status.

After receiving the multicast member management protocol message on the downstream flow interface, the MGW reports the message to the MGC. The MGC instructs the media gateway to send a multicast member management protocol message, such as an IGMP message, on the upstream flow interface. For the processing on the downstream flow interface, reference may be made to the case of FIG. 6. The upstream stream interface is configured to extend the signal igmpsrl. The signal is used by the MGC to indicate that the MGW sends an IGMP message on the designated upstream flow interface, and the signal parameter carries the content of the field in the IGMP message.

In addition to the above method in which the MGC controls the MGW to accept the report of the multicast member management protocol message on the downstream flow interface and instructs the MGW to send the multicast member management protocol message on the upstream flow interface, There is another method in which the MGW relies on configuration data to autonomously perform the aforementioned multicast member management functions. You need to configure support for the multicast member management protocol (such as IGMP) on the multicast routing device, configure the relationship between the multicast group and source address and the upstream and downstream flow interfaces, and the upstream router address, multicast group address mapping relationship, and group. Part or all of the source address mapping relationship. The configuration information may include the following items in part or in whole, but is not limited to the following:

( 2) The IP address of the IGMP protocol running on the interface. This address is the local address for sending and receiving IGMP messages. An interface may have multiple addresses. In addition, the multicast routing device may have multiple interfaces connected to the same IP. Therefore, it is necessary to configure the IP address used by the IGMP protocol on an IP network.

(3) The upstream flow interface corresponding to the multicast group address; the upstream flow interface of the shared tree of a multicast group. The multicast routing device sends a PIM-SM join/prune message of the multicast group to the upstream router through the interface.

(4) The upstream flow interface corresponding to the multicast group address and the multicast source address; the upstream flow interface of the source tree of a multicast source address of a multicast group. If the interface is the same as the upstream stream interface of the shared tree of the multicast group, it is not necessary to configure the source address separately. Therefore, it is better to configure the upstream stream interface of the source tree.

(5) The mapping relationship between the multicast group address mapping relationship and the multicast source address.

(6) User permission settings. Set the permissions of each user, including the range of multicast groups that can be joined. After receiving the IGMP request to join the multicast group, the multicast routing device may determine whether to discard the request message according to the permission configuration of the user. With the configuration of the present invention, the multicast routing device can forward the multicast data stream by itself.

(7) Configuration of various timers and parameters specified in the IGMP protocol.

The signal gdmap can be used to configure the multicast group address mapping and multicast source address mapping between the network where the upstream and downstream flow interfaces are located, and the mapping between the multicast group information and the upstream flow interface, that is, configuration (5). (6), (7). The H.248 protocol can be further extended to allow the MGC to instruct the MGW to modify other configurations.

The two methods described above can be used in combination.

As shown in FIG. 8, the MGC controls the MGW to enable the MGW to implement the multicast routing method provided by the embodiment of the present invention. The downstream flow interface of the MGW uses the multicast routing protocol, and the upstream flow interface uses the group in the MGW. The embodiment of the multicast routing method provided by the embodiment of the present invention specifically includes:

The MGW acts as a multicast router in the IP network 2, and uses the PIM-SM protocol; receives the PIM-SM-based join/prune message from the multicast router in the IP network 2;

After receiving the multicast data stream from the multicast router in the IP network 1, the MGW forwards the multicast data stream to the multicast router in the IP network 2.

The multicast routing protocol is used on the downstream flow interface of the MGW, and the multicast member management protocol is used on the upstream flow interface. The processing on the upstream stream interface is the same as in Figure 7. Received and processed on the downstream flow interface are multicast routing protocol messages, such as PIM-SM join/prune messages. The MGW maintains the multicast group member status of each downstream flow interface by receiving the multicast routing protocol message and the state of the multicast timer, and further, the device multicast member database is maintained, and the device multicast member database is changed, and then flows upstream. The interface sends the multicast group management protocol to join the multicast group and leave the multicast group to reflect the multicast subscription status of the MGW as a host.

After receiving the multicast routing protocol message on the downstream flow interface, the MGW reports the message to the MGC. The MGW indicates that the MGW sends a multicast member management protocol message, such as an IGMP message, on the upstream flow interface. The upstream signal is extended on the upstream interface. igmpsrl. This signal is used by the MGC to indicate that the MGW sends an IGMP message on the specified upstream flow interface. The signal parameter carries the content of the field in the IGMP message.

The downstream flow interface obtains the status of the multicast group member on the interface through the multicast routing protocol. The downstream network and the more downstream network closer to the host user can consider the upper layer when running the multicast routing protocol. The address of the upstream interface is the address of the upstream router on the multicast tree. The multicast tree does not bypass the downstream flow interface. A feasible method is that the multicast routing device of the present invention is used as an RP on the downstream flow interface. The downstream flow interface is an address of the RP, and the multicast data flow is forwarded to the downstream branch of the shared tree on the downstream flow interface, and the join/prune message sent by the downstream network is received and processed at the same time.

In addition to the above method in which the MGC controls the MGW to accept the reported multicast routing protocol message on the downstream flow interface and instructs the MGW to send the multicast member management protocol message on the upstream flow interface, there is another MGW that relies on the configuration data to autonomously perform the foregoing The method of multicast routing function. Support for multicast member management protocols (such as IGMP) and multicast routing protocols (such as PIM-SM) on the multicast routing device, and configure the relationship between each multicast group and source address and upstream and downstream flow interfaces. Part or all of the upstream router address, multicast group address mapping relationship, and multicast source address mapping relationship. The configuration information may include the following items in part or in whole, but is not limited to the following:

(5) The upstream flow interface corresponding to the multicast group address; the upstream flow interface of the shared tree of a multicast group. The multicast routing device sends a PIM-SM join/prune message of the multicast group to the upstream router through the interface. (6) The upstream flow interface corresponding to the multicast group address and the multicast source address; the upstream flow interface of the source tree of a multicast source address of a multicast group. If the interface and the upstream stream interface of the shared tree of the multicast group are the same, it is not necessary to configure the source address separately. Therefore, configuring the upstream stream interface of the source tree is better.

(7) The mapping relationship between the multicast group address mapping relationship and the multicast source address.

Use the gdmap command to configure the multicast group address mapping and multicast source address mapping between the network where the upstream and downstream flow interfaces reside, and the mapping between the multicast group information and the upstream flow interface. That is, configuration ( 5 ), ( 6 ), (7). The H.248 protocol can be further extended to allow the MGC to instruct the MGW to modify other configurations.

The two methods described above can be used in combination.

As shown in FIG. 9, the MGC controls the MGW to enable the MGW to implement the multicast routing method provided by the embodiment of the present invention. The downstream flow interface of the MGW uses the multicast routing protocol, and the upstream flow interface usage group of the MGW. The ninth embodiment of the multicast routing method provided by the embodiment of the present invention specifically includes:

The multicast routing protocol is used on both the downstream flow interface and the upstream flow interface of the MGW. Received and processed on the downstream flow interface is a multicast routing protocol message, such as a join/prune message of the PIM-SM. The MGW maintains the multicast group member status of each downstream flow interface by receiving the multicast routing protocol message and the state of the multicast timer, and further, maintaining the device multicast member database, and changing the device multicast member database to the upstream The stream interface sends a multicast routing protocol to join/prune operations. After receiving the multicast routing protocol message on the downstream flow interface, the media gateway reports the message to the MGC. The MGC instructs the MGW to send the multicast routing protocol message on the upstream flow interface. This requires extension of signals and events to the H.248 protocol.

The downstream flow interface obtains the multicast group member status on the interface through the multicast routing protocol. The downstream network and the more downstream network closer to the host user can consider the upstream flow interface address as a group when running the multicast routing protocol. For the address of the upstream router on the broadcast tree, the multicast tree does not bypass the downstream flow interface. A feasible method is that the multicast routing device of the present invention functions as an RP on the downstream flow interface, and the downstream flow interface is an RP. The address, on the downstream flow interface, forwards the multicast data stream to the downstream branch of the shared tree, and simultaneously receives and processes the join/prune message sent by the downstream network.

In addition to the above, the MGC controls the MGW to accept the reported multicast routing protocol message on the downstream flow interface and instructs the MGW to send the multicast routing protocol message on the upstream flow interface, and another MGW relies on the configuration data to autonomously complete the foregoing multicast routing. Functional method. You need to configure the multicast routing protocol (such as PIM-SM) on the multicast routing device, and configure the relationship between the multicast group and the source address and the upstream and downstream flow interfaces and the upstream router address. Part or all of the multicast group address mapping relationship and the multicast source address mapping relationship, such as the "bootstrap, message acquisition" of the PIM-SM. The configuration information may include the following items in part or in whole, but is not limited to the following. Various items:

(1) The interface that runs the PIM-SM protocol, and configures which interfaces need to support the sending and receiving of PIM-SM messages.

(2) The IP address of the PIM-SM protocol running on the interface. This address is the local address of the PIM-SM message. An interface may have multiple addresses. In addition, the multicast routing device may have multiple interfaces connected to the same IP. Therefore, it is necessary to configure the IP address used by the PIM-SM protocol on an IP network.

(3) The address of the RP. Different multicast groups may have different RPs. The multicast routing device may also obtain the RP address used by each multicast group from the received PIM-SM bootstrap message. But sometimes it is not Can get, depends on the configuration.

(4) The upstream router address of the interface; different multicast groups, or different multicast source addresses of the same multicast group, may have different upstream router addresses.

If the RP address or the multicast source address is obtained, the multicast routing device can obtain the address of the upstream router or the upstream router of the source tree through unicast routing, which is based on the RPF principle. However, if the multicast routing device may not be able to directly route with the RP or the like (for example, other media gateways are separated), the configuration method can also be implemented.

(5) The upstream flow interface corresponding to the multicast group address; the upstream flow interface of the shared tree of a multicast group. The multicast routing device sends a PIM-SM join/prune message of the multicast group to the upstream router through the interface.

(6) The upstream flow interface corresponding to the multicast group address and the multicast source address; the upstream flow interface of the source tree of a multicast source address of a multicast group. If the interface is the same as the upstream stream interface of the shared tree of the multicast group, it is not necessary to configure the source address separately. Therefore, it is better to configure the upstream stream interface of the source tree.

(8) Configuration of various timers and parameters specified by the PIM-SM protocol.

Among them, the four cases described in FIG. 6, FIG. 7, FIG. 8, and FIG. 9 may be partially or completely implemented on the same MGW. For example, the MGW runs the multicast member management protocol and the multicast routing protocol on the downstream flow interface, and integrates the multicast subscription subscription of the downstream branch of the multicast tree where the downstream flow interface is located and the local downstream network connected to the downstream flow interface. The multicast group member status of the host user maintains the multicast group member status of the downstream flow interface. In this case, the MGW needs to act as the DR (designated router) or win the assertion on the downstream flow interface. The change of the multicast group member status of the downstream flow interface affects the device multicast member database, and the corresponding swim flow interface processes the multicast group (with the multicast source address). Qualified or not) You can use the multicast member management protocol or the multicast routing protocol. You can use both protocols to join or leave the multicast group on the upstream network. Therefore, the configurations in the four cases of FIG. 6 to FIG. 9 may be required at the same time, and further configuration of a multicast protocol type selected by the multicast interface on the upstream flow interface may be further configured to the multicast member management. Type of protocol (IGMP, MLD, etc.) or type of multicast routing protocol (PIM-SM, PIM-DM, etc.). In this case, the multicast group on the downstream flow interface can correspond to not only the upstream flow interface but also the type of the multicast protocol. It is also necessary to further extend the H.248 protocol for the MGC to set and audit the correspondence between the multicast group on the MGW and the multicast protocol used on the upstream flow interface. Similar to the correspondence between the multicast group information and the upstream flow interface, there are three possible scenarios for the multicast group mentioned here, including the filtering of the multicast source address. The extension method may refer to the upa parameter of the previous gdmap signal, or update the parameter to further describe the correspondence between the multicast group and the multicast protocol used on the upstream stream interface. I won't go into details here.

In addition, the embodiment of the present invention further improves the media processing capability of the MGW. When the MGW forwards the multicast data stream, the multicast source address of the multicast data stream sent to the downstream flow interface is that the upstream stream interface receives the multicast data stream. The multicast source address or the mapped multicast source address of the multicast source address received by the upstream stream interface on the downstream stream interface. The MGC can set the MGW to send the data stream using the source address when receiving the data stream or to map the source address through the media gateway control protocol.

The signal events defined above can be sent to the ROOT terminal of the MGW. The gateway-level ROOT terminal processes multicast member management protocol messages, multicast routing protocol messages, and multicast data streams on each interface. If a multicast group and a multicast source address do not need to perform address mapping between the upstream and downstream networks, the multicast source address of the multicast data stream sent to the downstream flow interface is the upstream stream interface that receives the multicast data stream. The multicast source address and the multicast group address that serves as the destination address of the multicast data stream also remain unchanged. If a multicast group address needs to be mapped between the upstream and downstream networks, the destination address of the multicast data stream sent to the downstream flow interface, that is, the multicast group address, is modified to be the upstream stream interface receiving the multicast data stream. The multicast group address of the multicast group address on the downstream flow interface. If the source address of a multicast group needs to be mapped between the upstream and downstream networks, the multicast source address of the multicast data stream sent to the downstream flow interface is modified to be the upstream stream interface receiving the multicast data stream. The mapped multicast source address of the source address on the downstream flow interface. The signal events defined above can be delivered to the IP terminal of the MGW. For example, an H.248 IP terminal at the interface level can be created. You can configure or audit the upstream network and the downstream network by means of signals, or terminal-level attributes, or context-level attributes. The mapping between the multicast group address and/or the multicast source address, the correspondence between the multicast group and the upstream flow interface, and the correspondence between the multicast group and the multicast protocol used on the upstream flow interface. As shown in Figure 10, the multicast data stream is forwarded after the IP address of the interface is created. After receiving the multicast data stream from the upstream interface, the multicast data stream is transmitted through the downstream stream interface 1 according to the above attribute configuration. The network 1 is sent to the downstream network 1 corresponding to the downstream flow interface 1, and the multicast data stream is sent to the downstream network 2 corresponding to the downstream flow interface 2 through the downstream flow interface 2.

It can be understood that, in the four cases in the foregoing Embodiment 2 of the multicast routing method, the multicast routing device sends a multicast data stream to a downstream flow interface. In an actual application, the multicast routing device can simultaneously Multiple downstream flow interfaces send multicast data streams, and the processing methods for each of the lower interfaces are similar, so this specification does not describe them. It should be noted that the IGMP and PIM-SM protocols are used as an example in the present invention. Although the configuration of other protocols is not described, the use of other protocols is not excluded. When the MGC controls the MGW, this specification extends H.248. In the actual application, when the MGCP protocol is used between the MGC and the MGW, the MGCP protocol can be similarly extended, and the description is not repeated here. Further, the parameter names, formats, and the like used in the present specification are provided for convenience of explanation, and are not limited to parameter names, formats, and the like.

As shown in FIG. 11, the embodiment of the multicast routing apparatus provided by the present invention includes:

The trigger information acquiring unit 1101 is configured to obtain, from the downstream flow interface, trigger information that triggers a change of a state of the multicast group member on the downstream flow interface, where the trigger information includes the first multicast group information.

The database judging unit 1102 is configured to determine whether the change of the status of the multicast group member on the downstream flow interface causes the record of the multicast member database of the device to be changed, and the device multicast group member database summarizes the status of all the downstream flow interface multicast group members.

The interface determining unit 1103 is configured to: when the database determining unit determines that the change of the state of the multicast group member on the downstream flow interface causes the record of the multicast member database of the device to change, according to the correspondence between the multicast group information and the upstream flow interface, An upstream flow interface corresponding to the second multicast group information in the changed record in the multicast member database of the device;

The message sending unit 1104 is configured to: after the first message is configured according to the record changed in the device multicast member database, send the group to the upstream network corresponding to the upstream flow interface by using the upstream flow interface. The first message of the broadcast group information, the first message includes third multicast group information corresponding to the second multicast group information.

In a practical application, if the trigger information is a message requesting to join the multicast group, the message to join the multicast group includes the address of the host that requests to join the multicast group. The multicast routing device provided by the embodiment of the present invention further includes:

The permission judging unit is configured to determine, when the database judging unit determines that the state of the multicast group member on the downstream flow interface is changed, causing the host to have the permission to join the multicast group, if yes, triggering The interface determining unit searches for an upstream flow interface corresponding to the second multicast group information in the record changed in the device multicast member database according to the correspondence between the multicast group information and the upstream flow interface.

The multicast routing device provided by the embodiment of the present invention may further include:

a network address mapping table maintenance unit, configured to store a network address mapping table of a mapping relationship between a network address of an upstream network corresponding to the upstream flow interface and a network address of the downstream network corresponding to the downstream flow interface; a multicast group information update unit, configured to: When the first multicast group information includes the first multicast group address, the first mapping multicast group address of the first multicast group address in the upstream network is searched from the network address mapping table, and the first multicast group information is The first multicast group address is updated to the first mapped multicast group address; the trigger message sending unit sends the first message including the updated multicast group information;

Or

When the first multicast group information includes the first multicast group address and the first multicast source address, the first mapping multicast group address of the first multicast group address in the upstream network is searched from the network address mapping table, And updating, by the first multicast source address of the first multicast source address, the first multicast group address in the first multicast group information to the first mapped multicast group address, and the first multicast The first multicast source address in the information is updated to the first mapped multicast source address; the trigger message sending unit sends the first message including the updated multicast group information;

Or

When the first multicast group information includes the first multicast source address, the first multicast source address of the first multicast source address in the upstream network is searched from the network address mapping table, and the first multicast group information is obtained. In the middle The multicast source address is updated to the first mapped multicast source address; the trigger message sending unit sends the first message including the updated multicast group information.

Through the records in the network address mapping table, the addresses between different networks can be associated, so that multicast can proceed smoothly.

In a practical application, the multicast routing device needs to complete the forwarding of the multicast data stream. Therefore, the multicast routing device provided by the embodiment of the present invention further includes:

The multicast data stream receiving unit is configured to receive the multicast data stream of the multicast group from the upstream flow interface, and the multicast data stream sending unit is configured to distribute the multicast data stream according to the multicast group member status on the downstream flow interface.

In order to ensure the correct forwarding of the data stream, the multicast data stream updating unit provided by the multicast routing device provided by the embodiment of the present invention is further configured to save the multicast group address mapping relationship between the upstream network and the downstream network in the network address mapping table. Modifying the multicast group address of the multicast data stream according to the network address mapping table, and triggering the multicast data stream sending unit to distribute the multicast data stream according to the multicast group member status on the downstream flow interface;

Or

When the network address mapping table is used to save the multicast source address mapping relationship between the upstream network and the downstream network, the multicast source address of the multicast data stream is modified according to the network address mapping table, and the multicast data stream sending unit is triggered according to the downstream. The multicast group member status on the flow interface distributes the multicast data stream;

Or

It is also used to modify the multicast group address and multicast source address of the multicast data stream according to the network address mapping table when the network address mapping table stores the mapping between the multicast group address and the multicast source address between the upstream network and the downstream network. The triggering multicast data stream sending unit distributes the multicast data stream according to the multicast group member status on the downstream stream interface.

As shown in FIG. 12, the media gateway embodiment provided by the present invention includes:

The trigger information acquiring unit 1201 is configured to obtain, from the downstream flow interface, trigger information that triggers a change in the state of the multicast group member on the downstream flow interface, where the trigger information includes the first multicast group information.

The control information request sending unit 1202 is configured to send a control information request message to the media gateway controller, where the control information request includes the first multicast group information;

Control information receiving unit 1203, configured to receive response control information from the media gateway controller Requesting a control message for the message;

The database judging unit 1204 is configured to determine whether the change of the multicast group member status on the downstream flow interface causes the record of the multicast member database of the device to be changed, and the device multicast group member database summarizes the status of all the downstream flow interface multicast group members.

The interface determining unit 1205 is configured to: when the database determining unit determines that the change of the multicast group member status on the downstream flow interface causes the record of the multicast member database of the device to change, according to the correspondence between the multicast group information and the upstream flow interface, An upstream flow interface corresponding to the second multicast group information in the changed record in the multicast member database of the device;

The message sending unit 1206 is configured to: after the first message is configured according to the record changed in the device multicast member database, send the first message including the multicast group information to the upstream network corresponding to the upstream flow interface by using the upstream flow interface, The first message includes third multicast group information corresponding to the second multicast group information.

The media gateway provided by the embodiment of the present invention may further include: the media gateway provided by the embodiment of the present invention is required to record the corresponding relationship between the network addresses of different networks in different networks.

a network address mapping table maintenance unit, configured to store a network address mapping table of a mapping relationship between a network address of an upstream network corresponding to the upstream flow interface and a network address of the downstream network corresponding to the downstream flow interface; a multicast group information update unit, configured to: When the first multicast group information includes the first multicast group address, the first mapping multicast group address of the first multicast group address in the upstream network is searched from the network address mapping table, and the first of the multicast group information is obtained. The multicast group address is updated to the first mapped multicast group address; the trigger message sending unit sends the first message including the updated multicast group information;

Or

Or When the first multicast group information includes the first multicast source address, the first multicast source address of the first multicast source address in the upstream network is searched from the network address mapping table, and the first multicast group information is obtained. The first multicast source address is updated to the first mapped multicast source address; the trigger message sending unit sends the first message including the updated multicast group information.

In a practical application, the media gateway needs to complete the forwarding of the multicast data stream. Therefore, the media gateway provided by the embodiment of the present invention further includes:

Or

Corresponding to the media gateway, the embodiment of the present invention further provides a media gateway controller, and FIG. 13 describes an embodiment of the media gateway controller, including:

The control information request receiving unit 1301 is configured to receive a first message from the media gateway, where the first message includes the first multicast group information; The determining unit 1302 is configured to determine, according to the self-policy and the first multicast group information, whether to allow to join the multicast group.

The control information sending unit 1303 is configured to: when the determining unit determines that the multicast group is allowed to join the multicast group, send a control message that is allowed to join the multicast group, or send a control message that is not allowed to join the multicast group when the determining unit determines that the multicast group is not allowed to join the multicast group. .

Preferably, if the first message received by the control information request receiving unit further comprises a host requesting to join the multicast group;

The judging unit further determines, according to the host, whether to allow to join the multicast group.

In an actual application, in order to comply with the requirements of the multicast member management protocol, such as IGMP, the MGC provided by the embodiment of the present invention further includes:

The query trigger information sending unit is configured to send query trigger information to the media gateway when there is trigger of its own pre-configuration information.

As shown in FIG. 14, the first embodiment of the multicast routing system provided by the embodiment of the present invention includes: a multicast routing device 1401, configured to acquire, from a downstream flow interface, trigger information that triggers a change of a multicast group member state on a downstream flow interface. The trigger information includes the first multicast group information. If the status of the multicast group member on the downstream flow interface is changed, the record of the multicast member database of the device in the multicast group member state is changed. Corresponding relationship between the information and the upstream flow interface, searching for an upstream flow interface corresponding to the second multicast group information in the changed record in the device multicast member database; constructing the first message according to the record changed in the device multicast member database And sending, by the upstream flow interface, the first message to the upstream network corresponding to the upstream flow interface, where the first message includes third multicast group information corresponding to the second multicast group information;

The first network 1402 is configured to receive the first message.

Figure 15 illustrates a second embodiment of the multicast routing system provided by the present invention, including:

The media gateway 1501 is configured to obtain, from the downstream flow interface, trigger information that triggers a change of the state of the multicast group member on the downstream flow interface, where the trigger information includes the first multicast group information, and sends a control information request message to the media gateway controller.

The media gateway controller 1502 is configured to receive a control information request message, determine, according to the first multicast group information, whether to allow to join the multicast group, and send a control message that is allowed to join the multicast group when determining to allow the joining of the multicast group; The media gateway 1501 is further configured to receive a control message, and if the status of the multicast group member on the downstream flow interface is changed, the record of the multicast member database of the device group state of all the downstream flow interface multicast group members is changed, according to the multicast group. Corresponding relationship between the information and the upstream flow interface, searching for an upstream flow interface corresponding to the second multicast group information in the changed record in the device multicast member database; after constructing the first message according to the record changed in the device multicast member database, Sending, by the upstream flow interface, the first information, where the first message includes third multicast group information corresponding to the second multicast group information;

The first network 1503 is configured to receive the first message.

A person skilled in the art can understand that all or part of the steps in the method of implementing the above embodiments can be completed by a program to instruct related hardware. The program can be stored in a computer readable storage medium, and when executed, the program includes the following Steps:

The triggering information that triggers the change of the state of the multicast group member on the downstream flow interface is obtained from the downstream flow interface, where the trigger information includes the first multicast group information.

If the status of the multicast group member on the downstream flow interface is changed, the record of the device multicast member database that is in the state of the multicast group member is changed. The mapping between the multicast group information and the upstream flow interface is used to find and be An upstream flow interface corresponding to the second multicast group information in the changed record; constructing the first message according to the changed record in the device multicast member database, where the first message includes the third multicast group information, and the third multicast group information Corresponding to the second multicast group information;

The first message is sent to the upstream network corresponding to the upstream flow interface by using the found upstream flow interface; the storage medium mentioned above may be a read only memory, a magnetic disk or an optical disk.

The multicast routing method and system, the media gateway and the media gateway controller provided by the embodiments of the present invention are described in detail above. The description of the above embodiments is only used to help understand the method and the idea of the present invention; The present invention is not limited by the scope of the present invention, and the details of the present invention are not limited by the scope of the present invention.

Claims

Rights request

A multicast routing method, comprising:

Constructing a first message according to the changed record in the multicast member database of the device, where the first message includes third multicast group information, and the third multicast group information corresponds to the second multicast group information;

And sending, by the found upstream flow interface, the first message to an upstream network corresponding to the upstream flow interface.

2. The multicast routing method according to claim 1, wherein the trigger information includes an address of a host requesting to join the multicast group;

And obtaining the upstream flow interface of the media gateway that is found according to the first multicast group information and the correspondence between the multicast group information and the upstream flow interface, and further includes:

Determining whether the host has the right to join the multicast group;

If the host has the right to join the multicast group, the upstream flow interface of the media gateway that is found according to the first multicast group information and the correspondence between the multicast group information and the upstream flow interface is obtained.

The multicast routing method according to claim 1, wherein the method further comprises: maintaining a network address mapping table, wherein the network address mapping table stores an upstream network corresponding to the upstream flow interface and a downstream flow interface. Network address mapping relationship between downstream networks;

And if the network address mapping relationship between the upstream network corresponding to the upstream flow interface and the downstream network corresponding to the downstream flow interface is specifically a multicast group address mapping relationship between the upstream network and the downstream network, the third multicast group information includes a multicast group address; the multicast group address included in the third multicast group information is a multicast group address mapped by the corresponding multicast group address in the first multicast group information;

Or If the network address mapping relationship between the upstream network corresponding to the upstream network interface and the downstream network interface is the multicast source address mapping relationship between the upstream network and the downstream network, the third multicast group information includes a multicast source address; the multicast source address included in the third multicast group information is a multicast source address mapped by a corresponding multicast source address in the first multicast group information;

Or

If the network address mapping relationship between the upstream network corresponding to the upstream network interface and the downstream network interface is the multicast group address mapping relationship and the multicast source address mapping relationship between the upstream network and the downstream network, The third multicast group information includes a multicast group address and a multicast source address. The multicast group address included in the third multicast group information is mapped by the corresponding multicast group address in the first multicast group information. The multicast source address, the multicast source address included in the third multicast group information is a multicast source address mapped by the corresponding multicast source address in the first multicast group information.

The method of multicast routing according to claim 1, wherein the method further comprises: receiving, by the upstream flow interface, a multicast data stream from the upstream network;

The multicast data stream is distributed according to the multicast group member status of the downstream flow interface.

The multicast routing method according to claim 4, wherein the method further comprises: maintaining a network address mapping table, wherein the network address mapping table stores a network address mapping relationship between the upstream network and the downstream network;

If the network address mapping relationship between the upstream network and the downstream network is specifically a multicast group address mapping relationship between the upstream network and the downstream network, the multicast data stream is further distributed according to the multicast group member status on the downstream flow interface. :

Modifying the multicast group address of the multicast data stream according to the network address mapping table, and performing the step of distributing the multicast data stream according to the state of the multicast group member on the downstream flow interface;

Or

If the network address mapping relationship between the upstream network and the downstream network is specifically a multicast source address mapping relationship between the upstream network and the downstream network, the multicast data stream is further distributed according to the state of the multicast group member on the downstream flow interface. :

Modifying the source address of the multicast data stream of the multicast data stream according to the network address mapping table, and performing the step of distributing the multicast data stream according to the state of the multicast group member on the downstream flow interface;

Or If the network address mapping relationship between the upstream network and the downstream network is specifically the multicast group address mapping relationship and the multicast source address mapping relationship between the upstream network and the downstream network, the multicast group member status is distributed according to the downstream flow interface. The multicast data stream further includes:

Modifying the multicast group address and the source address of the multicast data stream according to the network address mapping table, and performing the step of distributing the multicast data stream according to the state of the multicast group member on the downstream flow interface.

The multicast routing method according to claim 3 or 5, wherein the network address mapping table is saved by the media gateway.

The multicast routing method according to claim 6, wherein the method further comprises: controlling, by the media gateway controller, the media gateway to update the network address mapping table.

The multicast routing method according to claim 1, wherein the media gateway saves a correspondence between the multicast group information and an upstream stream interface.

The multicast routing method according to claim 8, wherein the method further comprises: controlling, by the media gateway controller, the correspondence between the multicast group information and the upstream flow interface by the media gateway Update.

The multicast routing method according to claim 1, wherein when the correspondence between the multicast group information and the upstream flow interface is saved by the media gateway controller, the obtaining is performed according to the first The upstream flow interface of the media gateway that is found by the multicast group information and the correspondence between the multicast group information and the upstream flow interface is specifically:

Obtaining the upstream flow interface that is found by the media gateway controller, where the upstream flow interface is searched by the media gateway controller according to the first multicast group information and the correspondence between the multicast group information and the upstream flow interface.

The multicast routing method according to claim 1, wherein the upstream stream interface corresponding to the second multicast group information in the changed record is multiple;

The step of constructing the first message according to the changed record in the device multicast member database is:

Constructing a first message for each upstream flow interface according to the changed record in the device multicast member database;

The step of sending the first message to the upstream network corresponding to the upstream flow interface by using the searched upstream flow interface is specifically: Sending, by the found upstream flow interface, the first message configured for the upstream flow interface to the upstream network corresponding to the upstream flow interface.

The multicast routing method according to claim 1, wherein the upstream flow interface uses a multicast routing protocol or a multicast member management protocol;

A multicast routing protocol or a multicast member management protocol is used on the downstream flow interface.

13. A computer program product, characterized in that the computer program product comprises computer program code, and when the computer program code is executed by a computer, the computer program code can cause the computer to execute claim 1 The steps of any of the 11 items.

14. A computer readable storage medium, wherein the computer readable storage medium stores computer program code, and when the computer program code is executed by a computer, the computer program code can cause the computer to execute The steps of any one of claims 1 to 11.

15. A media gateway, comprising:

The media gateway according to claim 15, further comprising: a network address mapping table maintenance unit, configured to maintain a network address mapping table, where the network address mapping table stores an upstream network corresponding to the upstream flow interface a mapping relationship between the network address and the network address of the downstream network corresponding to the downstream flow interface;

The multicast group information update unit is configured to: when the first multicast group information includes the first multicast group address, search for the first multicast group address from the network address mapping table in the first network of the upstream network Mapping the multicast group address, updating the first multicast group address in the multicast group information to the first mapped multicast group address; triggering the message sending unit to send the first message including the updated multicast group information ;

Or

When the first multicast group information includes the first multicast group address and the first multicast source address, the first mapping group of the first multicast group address in the upstream network is searched from the network address mapping table. The broadcast group address and the first multicast source address of the first multicast source address in the upstream network, and the first multicast group address in the first multicast group information is updated to the first mapped multicast group address, The first multicast source address in the first multicast information is updated to the first mapped multicast source address; triggering the message sending unit to send a first message including the updated multicast group information;

Or

When the first multicast group information includes the first multicast source address, the first mapping multicast source address of the first multicast source address in the upstream network is searched from the network address mapping table, and the first The first multicast source address in the multicast group information is updated to the first mapped multicast source address, and the message sending unit is triggered to send the first message including the updated multicast group information.

The media gateway of claim 15, further comprising:

a multicast data stream receiving unit, configured to receive a multicast data stream of the multicast group from the upstream flow interface; the multicast data stream sending unit, configured to distribute the multicast data according to the status of the multicast group member on the downstream flow interface flow.

The media gateway of claim 17, further comprising:

a network address mapping table maintenance unit, configured to maintain a network address mapping table, where the network address mapping table stores a mapping relationship between a network address of the upstream network corresponding to the upstream flow interface and a network address of the downstream network corresponding to the downstream flow interface;

a multicast data stream update unit, configured to be in the network address mapping table and stored on the network When the multicast group address mapping relationship between the upstream network and the downstream network is performed, the multicast group address of the multicast data stream is modified according to the network address mapping table, and the multicast data stream sending unit is triggered according to the downstream stream. The multicast group member status on the interface distributes the multicast data stream;

Or the mapping between the network address of the network is a multicast source address mapping relationship between the upstream network and the downstream network, and modifying the multicast source address of the multicast data stream according to the network address mapping table, triggering the The multicast data stream sending unit distributes the multicast data stream according to the multicast group member status on the downstream flow interface;

Or the mapping between the network address of the network and the multicast group address and the multicast source address mapping relationship between the upstream network and the downstream network, and modifying the multicast group of the multicast data flow according to the network address mapping table. The address and the multicast source address trigger the multicast data stream sending unit to distribute the multicast data stream according to the multicast group member status on the downstream flow interface.

19. A media gateway controller, comprising:

The control information sending unit is configured to: when the determining unit determines that the multicast group is allowed to join the multicast group, send a control message that is allowed to join the multicast group, or send the multicast group not allowed when the determining unit determines that the multicast group is not allowed to join the multicast group. Control message.

The media gateway controller according to claim 19, wherein the control information request message received by the control information request receiving unit includes a host address that requests to join a multicast group; The host address determines whether it is allowed to join the multicast group.

The media gateway controller according to claim 19 or 20, further comprising: a network address mapping table maintenance unit, configured to send a setting of the network address mapping table to the media gateway / or update information.

22. A multicast routing system, comprising:

The first network is configured to receive the first message.