WO2009094921A1

WO2009094921A1 - Method for multicast forwarding and multicast router

Info

Publication number: WO2009094921A1
Application number: PCT/CN2009/070133
Authority: WO
Inventors: Lin Xia; Qinfeng Gu; Yong Chen
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2008-01-22
Filing date: 2009-01-14
Publication date: 2009-08-06
Also published as: CN101222425A; CN101222425B

Abstract

A method for multicast forwarding which is used in the multicast among different internet protocol networks is disclosed. The method includes the following steps: receiving the first multicast group joining request from the first internet protocol network which the host is located in; the first multicast group joining request is sent by the host when it requests to join the multicast group which is corresponding to the multicast source located in the second internet protocol network; joining the multicast group by the way of acting as the agent of the host; receiving the multicast data of the multicast group from the second internet protocol network and sending the multicast data of the multicast group to the host. The corresponding computer program product, computer readable storage medium and multicast router are also disclosed. The multicast source can be used, wherein the multicast source and the host are located in different internet protocol networks.

Description

Multicast forwarding method and multicast router

This application claims priority to Chinese Patent Application No. 200810000806.5, entitled "Multicast Forwarding Method and Multicast Router", filed on January 22, 2008, the entire contents of in.

Technical field

The present invention relates to the field of network technologies, and in particular, to a multicast forwarding method and a multicast router.

Background technique

Multicast is an important Internet Protocol (IP) technology. When certain users on the network require specific information, the multicast sender (ie, the multicast source) sends the information only once, with the help of the multicast routing protocol. Tree routing is established for multicast packets, and the transmitted information begins to be copied and distributed at the forks as far as possible. There are three main entities in the multicast: a multicast source, which is used to send multicast packets to the network, a multicast router, which is used to forward multicast packets, and a receiver, which is used to receive multicast packets.

On the receiver side, the protocol used is the Internet Group Management Protocol (IMB) or the Multicast Listener Discovery (MLD) protocol, where the Internet Group Management Protocol is applied to Internet Protocol Version 4 (IPV4). Network, Multicast Listener Discovery Protocol is applied to the Internet Protocol Version 6 (IPV6) network. The above two protocols define the control mechanism for the user to join the specified group; the Internet Group Management Protocol is the host-to-router signaling mechanism used by the Internet Protocol Multicast on the end network, and is divided into two functional parts: the host side and the router side. The receiver host reports the group membership to the shared network, and all routers in the same network segment that have enabled the Internet Group Management Protocol/Multicast Listening Discovery Protocol function elect the querier, and the querier periodically sends the querier to the shared network. The group member queries the message, and the receiver host responds after receiving the query message to report the group membership, and the querier refreshes the existence information of the group member according to the received response.

All recipient hosts participating in the multicast transmission must implement the Internet Group Management Protocol/Multicast Listener Discovery Protocol. A host participating in the Internet Protocol multicast transmission can join or leave the multicast group at any time, anywhere, and with the total number of members without restrictions. Routers that support multicast do not need or can save the membership of all hosts. It only knows whether there is a receiver of a multicast group, that is, a group member, on the network segment connected to each interface through the Internet Group Management Protocol. Each host only needs to save which multicast groups it has joined.

In a multicast network, use the Internet Group Management Protocol proxy (IGMP Proxy) or multicast listener The current protocol proxy (MLD Proxy) technology can avoid the use of some complex multicast routing protocols, such as the Protocol Independent Multicast (PIM). Suppose a router acts as a proxy for the Internet Group Management Protocol. After receiving a user-initiated Internet Group Management Protocol join request, the Internet Group Management Protocol uplink port of a specific multicast group has only one in the router; when another user requests to join, The Internet Group Management Protocol request is also sent to the router. At this time, the router non-multicast technology is utilized in many aspects, such as Internet Protocol Television (IPTV). When the IPTV is actually applied, the data plane and the control plane need to be separated in different virtual private networks (VPNs). Generally, the multicast data is transmitted through the public network, and the Internet Protocol address of the set-top box is placed in a Layer 3 Virtual Private Network (L3VPN).

In the process of implementing the present invention, the inventors have found that at least the following problems exist in the prior art: The multicast data needs to be transmitted on the public network, so the multicast source needs to be located on the public network, and in practical applications, the multicast source and the receiver They may all be located in a virtual private network, and these virtual private networks are all connected by the same multicast router. At this time, multicast cannot be implemented in the above manner, so that the multicast source located in the virtual private network is not fully utilized, and the multicast source is not fully utilized. The resource utilization of the system.

Summary of the invention

The embodiment of the present invention provides a multicast forwarding method and a multicast router. The technical solution provided by the embodiment of the present invention can be used to make a multicast source that is in a different network protocol network with the host.

The purpose of the embodiment of the present invention is achieved by the following technical solutions:

The present invention provides a multicast forwarding method, which is applied to multicast between different internet protocol networks, including:

Receiving a first multicast group join request, the first multicast group join request is from a first internet protocol network where the host is located, and the host requests to join a multicast group corresponding to the multicast source located in the second internet protocol network. Sending the first multicast group join request;

Representing the host to join the multicast group;

Receiving multicast data of the multicast group from the second internet protocol network, and transmitting multicast data of the multicast group to the host. The present invention also provides a computer program product, comprising: computer program code, when the computer program code is executed by a computer, the computer program code can cause the computer to perform a multicast forwarding method Any one step.

The present invention also provides a computer readable storage medium, the computer storing computer program code, when the computer program code is executed by a computer, the computer program code can cause the computer to perform a multicast forwarding method Any one step.

The invention also provides a multicast router, comprising:

a request receiving unit, configured to receive a first multicast group join request, where the first multicast group join request is from a first internet protocol network where the host is located, and the host requests to join a multicast source located in the second internet protocol network. Sending the first multicast group join request when the corresponding multicast group is used;

a proxy unit, configured to: after the request receiving unit receives the first multicast group join request, proxy the host to join the multicast group;

a data receiving unit, configured to receive data of the multicast group from the second internet protocol network;

a data sending unit, configured to send data of the multicast group to the host.

It can be seen from the foregoing technical solutions provided by the embodiments of the present invention that, in this embodiment, the multicast protocol proxy unit can implement the multicast protocol proxy function in the multicast router, so that the host located in the internet protocol network can join the multicast. The source is located in a multicast group of another internet protocol network. The above-mentioned internet protocol network may be a virtual private network, so that the multicast source located in another internet protocol network is utilized, the utilization of system resources is improved, and multicast can be enabled. The scope of application is wider.

DRAWINGS

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

2 is a schematic diagram of internal functions of a multicast router according to an embodiment of the present invention;

FIG. 3 is a structural diagram of an embodiment of a multicast router 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 embodiments of the present invention are mainly applied to a case where a multicast source and a host are respectively located in different Internet Protocol networks, so that multicast sources and hosts located in different Internet Protocol networks can implement multicast forwarding. FIG. 1 is a flowchart of an embodiment of a multicast forwarding method according to an embodiment of the present invention, including: 101. Receive a first multicast group join request, where the first multicast group join request is from a first internet protocol network where the host is located, The foregoing host sends the first multicast group join request when requesting to join the multicast group corresponding to the multicast source located in the second internet protocol network;

The first internet protocol network may be a virtual private network, or may be a network where other hosts that need to join the multicast group are located, such as a public internet protocol network, a private internet protocol network, etc.; the first multicast group join request may include joining Information of the multicast group, information of the host requesting to join the multicast group, etc. 102. The proxy host joins the multicast group;

The step of the proxy host joining the multicast group may specifically include four steps a, b, c, and d. a. The first multicast protocol unit processes the first multicast group join request. The first multicast protocol unit is allocated for the first internet protocol network. The broadcast protocol unit may be specifically configured according to an interface on the multicast router. Generally, one interface corresponds to one internet protocol network, but it does not exclude that multiple interfaces correspond to the same internet protocol network, or one interface corresponds to multiple different interfaces. After the first multicast group join request is received by an interface, the first multicast protocol unit corresponding to the interface is triggered to process the first multicast group join request;

The process of processing the first multicast group join request by the first multicast protocol unit may include: adding the host that sends the first multicast group join request to the first member list maintained by the multicast group; and receiving the first multicast group The interface that joins the request joins the first multicast forwarding table established for the above multicast group.

If the first member list already exists, the host is added to the existing first member list. If the first member list does not exist, the first member list is created, and the host is added to the newly created first member list. . If the first multicast forwarding table already exists, the interface is directly added to the existing first multicast forwarding table. If the first multicast forwarding table does not exist, the first multicast forwarding table is created, and the interface is added. New first multicast forwarding table.

If the first member list does not exist, or exists, but the entry is empty, it indicates that the corresponding first Internet Protocol network does not have the host joining the multicast group. In this case, the multicast group join request needs to be sent to the multicast source; It is indicated that the host has joined the multicast group in the first Internet Protocol network, and the multicast data of the multicast group is sent to the first Internet Protocol network. Therefore, the multicast group join request is not sent to the multicast source at this time. The first multicast protocol proxy unit sends a second multicast group join request to the second multicast protocol unit by using a preset manner, where the first multicast protocol proxy unit corresponds to the first multicast protocol unit, and the second group The multicast group join request is corresponding to the first multicast group join request, and the second multicast group protocol unit is allocated for the second internet protocol network where the multicast source of the multicast group is located.

The second internet protocol network may also be a virtual private network, or may be other types of internet protocol networks where the multicast source is located, such as a public internet protocol network, a private internet protocol network, etc., and the type of the second internet protocol network may be the same. The types of an internet protocol network are the same or different.

The preset mode may be a virtual interface mode, or other manners, such as a data channel, that can connect the first multicast protocol proxy unit and the second multicast protocol unit. If the virtual interface is used, the first multicast protocol proxy unit is bound to one end of the virtual interface, that is, the first Internet Protocol network where the host is located, and the other end is bound to the second multicast protocol. The unit, that is, the second internet protocol network where the multicast source is located. At this time, the virtual interface functions as a multicast protocol proxy in the first internet protocol network, and functions as a multicast protocol in the second internet protocol network.

The information about the host that the second multicast group joins the request to join the multicast group is the information of the virtual interface in the first multicast protocol proxy unit, which may be a globally unique internet protocol network address in the multicast router. , logo, etc.

The second multicast group join request corresponds to the first multicast group join request. The second multicast group join request and the first multicast group join request are both requested to join the same multicast group, but the host is different. The host to which the multicast group joins the request is the host located in the first Internet Protocol network, and the host to which the second multicast group joins the request is the first multicast protocol proxy unit. When the virtual interface is connected, the first and second multicast groups join. The address of the requested host is the address of the end of the virtual interface that is connected to the first multicast protocol proxy unit.

c. The second multicast protocol unit processes the second multicast group join request.

The specific process of the second multicast protocol unit processing the second multicast group join request is similar to the process of the first multicast protocol unit processing the first multicast group join request, which may include: sending the second multicast group to join the request The first multicast protocol proxy unit joins the second member list maintained for the multicast group; the virtual interface that receives the second multicast group join request is added to the second multicast forwarding table established by the multicast group.

If the second member list already exists, the first multicast protocol proxy unit is directly added to the existing second member list; if the second member list does not exist, the second member list is newly created, and the first multicast is The protocol agent unit joins the newly created second member list. If the second multicast forwarding table is already stored Add the virtual interface to the existing second multicast forwarding table. If the second multicast forwarding table does not exist, create a second multicast forwarding table and add the virtual interface to the newly created second multicast forwarding table. .

If the second member list does not exist, or exists, but the entry is empty, it means that the protocol proxy unit does not join the multicast group. In this case, the multicast group join request needs to be sent in the direction of the multicast source; otherwise, the description is The protocol proxy unit has been added to the multicast group. The multicast data of the multicast group is sent to the multicast router. Therefore, the multicast group join request is not sent to the multicast source.

d. The second multicast protocol proxy unit sends a third multicast group join request to the second internet protocol network, where the second multicast protocol proxy unit corresponds to the second multicast protocol unit, and the third multicast group join request The second multicast group join request corresponds.

The host information of the request that the third multicast group joins the request to join the multicast group is the information of the multicast router, which may be the global unique network address, identifier, and the like of the multicast router. The third multicast group join request corresponds to the second multicast group join request, that is, the third multicast group join request and the second multicast group join request are both requested to join the same multicast group, but the host is different, the third group The host to which the broadcast group joins the request is the second multicast protocol proxy unit.

103. Receive multicast data of the multicast group from a second internet protocol network.

Specifically, the multicast data of the multicast group from the second internet protocol network may be received by the second multicast protocol unit.

104. Send multicast data of the multicast group to the host.

The specific sending process may be as follows: the multicast data is sent to the virtual interface according to the second multicast forwarding table; the second multicast forwarding table stores the virtual hosts corresponding to the virtual interfaces, and thus the host can join the multicast group. The virtual data is sent to the virtual interface according to the record of the second multicast forwarding table; the first multicast protocol unit receives the multicast data from the virtual interface; and receives the first multicast group according to the first multicast forwarding table. The interface that joins the request sends the multicast data to the host; because the first multicast forwarding table stores which hosts in the network corresponding to the interface are added to the multicast group, it can be determined according to the record of the first multicast forwarding table. Which interfaces the multicast data is sent to.

As can be seen from the above, in this embodiment, a multicast protocol proxy function can be implemented in the multicast router, so that the host located in the Internet Protocol network can join the multicast group whose multicast source is located in another Internet Protocol network. The foregoing Internet Protocol network can be The virtual private network enables the use of multicast sources located in another Internet Protocol network, improves the utilization of system resources, and can make the application of multicast wider. It should be noted that the first internet protocol network in the embodiment of the present invention is a network where the host is located, and thus the number of the first internet protocol network may be multiple, and the corresponding first multicast protocol unit and multicast protocol proxy unit. There may be more than one, and the first multicast protocol unit and the multicast protocol proxy unit corresponding to each first internet protocol network may be separately operated, and the multicast forwarding between the first internet protocol networks does not mutually influences.

The following is an example of the internal function of the multicast router provided by the embodiment of the present invention. The following is an example of the internal function of the multicast router provided by the embodiment of the present invention. Shown as follows:

For Virtual Private Network A (VPN-A):

Virtual interface 1/virtual interface 2/virtual interface 3 is an ordinary Layer 3 interface configured with an Internet Protocol address. The Internet Protocol address is Internet Protocol Address 1-1/Internet Protocol Address 2-1/Internet Protocol Address 3-1, Internet Group Management Protocol is enabled, Internet Group Management Protocol join request can be received, and Internet Group Management Protocol can be processed. Request, maintain Internet group management agreement membership, etc. Virtual interface 1/virtual interface 2/virtual interface 3 is the uplink interface corresponding to the Internet Group Management Protocol proxy.

(Upstream Interface), at this time, the addresses configured on the virtual interface are respectively Internet Protocol Address 1-2/Internet Protocol Address 2-2/Internet Protocol Address 3-2, respectively, and Virtual Private Network B/Virtual Private Network C/Virtual Private Network D corresponds to, wherein, Internet Protocol Address 1-1/Internet Protocol Address 1-2, Internet Protocol Address 2-1/Internet Protocol Address 2-2, Internet Protocol Address 3-1/Internet Protocol Address 3-2 may belong to The same network segment.

Interface 1 / Interface 2 / Interface 3 are different interfaces belonging to different virtual private networks, respectively, enabling the Internet Group Management Protocol, receiving Internet Group Management Protocol join requests from different virtual private network users, processing Internet Group Management Protocol join requests, and maintaining the Internet. Group management agreement membership, etc.

The multicast router may further include the following functional units: a multicast protocol unit, that is, a multicast routing protocol unit such as an independent multicast protocol; and a virtual interface management unit, which provides functions for creating, managing, and the like of an Internet group management protocol proxy virtual interface. The Multicast Forwarding Information Base (MFIB) management unit manages the multicast forwarding entries so that the multicast data can be correctly copied from the inbound interface to the outgoing interface and forwarded. The multicast data is forwarded according to the forwarding entry in the multicast forwarding entry. Take the virtual private network A and the virtual private network B as an example to describe the process:

First, a special virtual interface is built as a virtual private network multicast proxy interface; this virtual interface is bound to the virtual private network A where the multicast source is located, and the virtual private network B where the host is located. The virtual interface is configured as a virtual private network B. The Internet Group Management Protocol proxy uplink interface; enables the Internet Group Management Protocol function of this virtual interface in Virtual Private Network A.

You can create a virtual interface by using the following commands:

[R] interface igmp-proxy 1

You can bind the virtual interface to virtual private network A and virtual private network B by the following command:

[R-igmp-proxy-1] ip address 10.0.0.1 bind vpn-a

[R-igmp-proxy-1] ip address 10.0.0.2 bind vpn-b

The Internet Group Management Protocol proxy function in Virtual Private Network b can be enabled by the following command:

[R-l] ip vpn-instance vpn-b

[R- 1 -vpn-instance-vpn-b] igmp proxy enable

You can enable the Internet Group Management Protocol and Internet Group Management Protocol proxy uplink function on the virtual interface by using the following commands:

[R-igmp-proxy-1] vpn-instance vpn-a igmp enable

[R-igmp-proxy-1] vpn-instance vpn-b igmp-proxy upsteam

The virtual interface can be created by the above command.

In the virtual private network B, the interface enabled with the Internet Group Management Protocol receives the first multicast group join request from the user, and is set to the multicast group G (the first multicast group when the Internet Group Management Protocol version 3 is selected) Adding a request will have a source address), then:

The Internet Group Management Protocol unit of the virtual private network B processes the first multicast group join request to maintain the membership group relationship; the Internet Group Management Protocol unit of the virtual private network B notifies the Internet group of the virtual private network B by the first multicast group join request The management protocol proxy unit causes the Internet Group Management Protocol proxy unit of the virtual private network B to proxy the first multicast group join request, and sends the second multicast group join request corresponding to the first multicast group join request from the virtual interface 1 to The Internet Group Management Protocol unit of the virtual private network A, wherein the source address of the multicast request is modified to the Internet Protocol address 1-2, that is, the Internet Protocol address to which the virtual private network B belongs on the virtual interface 1; The group management protocol unit notifies the multicast forwarding entry unit of the virtual private network B, and adds the interface that receives the request to the first multicast forwarding. Publish, specifically can be added to the outbound interface list in the first multicast forwarding table.

After the Internet Group Management Protocol unit in the virtual private network A receives the second multicast group join request on the virtual interface 1, the Internet Group Management Protocol unit of the virtual private network A processes the second multicast group join request, and maintains the member group. Notifying the Internet Group Management Protocol proxy unit of the virtual private network A, causing the Internet Group Management Protocol proxy unit of the virtual private network A to proxy the second multicast group access request, and sending a third multicast group join request to the upstream router, thereby Obtaining the multicast data. At the same time, the multicast forwarding entry of the virtual private network A is notified, and the virtual interface 1 that receives the request is added to the second multicast forwarding table, and the interface can be added to the outbound interface list in the second multicast forwarding table. .

After the multicast data corresponding to the multicast group G arrives at the router, the Internet group management protocol unit of the virtual private network A receives the multicast data, and then according to the second multicast forwarding table of the multicast forwarding entry of the virtual private network A, The virtual interface 1 sends the multicast data. After receiving the multicast data packet from the virtual interface 1, the Internet Group Management Protocol unit of the virtual private network B receives the first multicast forwarding table according to the multicast forwarding entry of the virtual private network B. Copy the multicast data packet to interface 1.

Figure 3 is a diagram showing the structure of a multicast router according to an embodiment of the present invention, including:

The request receiving unit 301 is configured to receive a first multicast group join request, where the first multicast group join request is from a first internet protocol network where the host is located, and the host requests to join a multicast source located in the second internet protocol network. The first multicast group join request is sent when the corresponding multicast group is used;

The proxy unit 302 is configured to: after the request receiving unit 301 receives the first multicast group join request, the proxy host joins the multicast group;

The proxy unit 302 mainly includes: a first multicast protocol unit, configured to process a first multicast group join request after the request receiving unit receives the first multicast group join request; a proxy unit, configured to send, after the first multicast protocol unit receives the first multicast group join request, a second multicast group join request corresponding to the first multicast group join request by using a preset manner; the second multicast protocol a unit, configured to receive a second multicast group join request, and process a second multicast group join request; the second multicast protocol proxy unit sends, after the second multicast protocol unit receives the second multicast group join request, The second multicast group join request corresponds to the third multicast group join request.

Further, if the preset mode is the virtual interface mode, the multicast router provided by the embodiment of the present invention may further include: a virtual interface allocation unit, configured to allocate a virtual interface to the first multicast protocol proxy unit and the second multicast protocol unit in advance. . The data receiving unit 303 is configured to receive data of a multicast group from the second internet protocol network, where the second multicast protocol unit receives the multicast data of the multicast group from the second internet protocol network after the data receiving unit 303 receives The multicast data is sent to the virtual interface according to the second multicast forwarding table.

The data sending unit 304 is configured to send data of the multicast group to the host.

After receiving the multicast data from the virtual interface, the first multicast protocol unit sends the multicast data to the interface that receives the first multicast group join request according to the first multicast forwarding trigger data sending unit 304.

As can be seen from the above, in this embodiment, a multicast protocol proxy function can be implemented in the multicast router, so that the host located in the Internet Protocol network can join the multicast group whose multicast source is located in another Internet Protocol network. The foregoing Internet Protocol network can be The virtual private network enables the use of multicast sources located in another Internet Protocol network, improves the utilization of system resources, and can make the application of multicast wider.

It will be understood by those skilled in the art that all or part of the steps of implementing the foregoing embodiments may be performed by a program to instruct related hardware, and the program may be stored in a computer readable storage medium. , including the following steps:

Representing the host to join the multicast group;

Receiving multicast data of the multicast group from the second internet protocol network, and transmitting multicast data of the multicast group to the host.

The above-mentioned storage medium may be a read only memory, a magnetic disk or an optical disk or the like.

The multicast forwarding method and the multicast router 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. Meanwhile, for those skilled in the art, based on The present invention is not limited by the scope of the present invention.

Claims

Rights request

A multicast forwarding method, which is applied to multicast between different internet protocol networks, and is characterized in that:

Representing the host to join the multicast group;

2. The multicast forwarding method according to claim 1, wherein the proxy joining the host to the multicast group is specifically:

The first multicast protocol unit processes the first multicast group join request, and the first multicast protocol unit allocates the first internet protocol network;

The first multicast protocol proxy unit corresponding to the first multicast protocol unit sends a second multicast group join request to the second multicast protocol unit by using a preset manner, the second multicast group join request and the The first multicast group join request is corresponding, and the second multicast group protocol unit is allocated to the second internet protocol network;

The second multicast protocol unit processes the second multicast group join request;

a second multicast protocol proxy unit corresponding to the second multicast protocol unit sends a third multicast group join request to the second internet protocol network, the third multicast group join request and the second group The broadcast group force input request corresponds.

The multicast forwarding method according to claim 2, wherein the first multicast protocol proxy unit sends the second multicast group to the second multicast protocol unit by using a virtual interface created in advance Into the request.

The multicast forwarding method according to claim 3, wherein the processing, by the first multicast protocol unit, the first multicast group join request is:

Adding the host that sends the first multicast group join request to the first member list maintained by the multicast group;

Adding the interface that receives the first multicast group join request to the first established by the multicast group Multicast forwarding table.

The multicast forwarding method according to claim 4, wherein the first multicast protocol proxy unit further includes: before sending the second multicast group join request to the second multicast protocol unit by using a preset manner:

Determining whether there is another host in the first member list before adding the host to the first member list. If there is no other host, the first multicast protocol proxy unit sends the second multicast protocol unit to the second multicast protocol unit by using a preset manner. The second multicast group joins the request.

The multicast forwarding method according to claim 4 or 5, wherein the processing, by the second multicast protocol unit, the second multicast group join request is:

Adding, by the first multicast protocol proxy unit that sends the second multicast group join request, to the second member list maintained by the multicast group;

The virtual interface that receives the second multicast group join request is added to the second multicast forwarding table established by the multicast group.

The multicast forwarding method according to claim 6, wherein the second multicast protocol proxy unit further includes: before transmitting the third multicast group join request to the second internet protocol network:

Determining whether there is another multicast protocol proxy unit in the second member list before adding the first multicast protocol proxy unit to the member list, if there is no other multicast protocol proxy unit, the second multicast protocol proxy unit Sending a third multicast group join request to the second internet protocol network.

The multicast forwarding method according to claim 6, wherein the receiving the multicast data of the multicast group from the second internet protocol network, and sending the multicast group to the host The multicast data is specifically:

The second multicast protocol unit receives multicast data of the multicast group from the second internet protocol network;

And sending the multicast data to the virtual interface according to the second multicast forwarding table;

The first multicast protocol unit receives the multicast data from the virtual interface;

And sending, by the interface that receives the first multicast group join request, the multicast data to the host according to the first multicast forwarding table.

9. A computer program product, characterized in that the computer program product comprises computer program code, when the computer program code is executed by a computer, the computer program The code may cause the computer to perform the steps of any one of claims 1 to 8.

10. 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 8.

A multicast router, comprising:

The multicast router according to claim 11, wherein the proxy unit comprises: a first multicast protocol unit, configured to: after the request receiving unit receives the first multicast group join request, Processing the first multicast group join request;

a first multicast protocol proxy unit, configured to send, by using a preset manner, a second corresponding to the first multicast group join request, after the first multicast protocol unit processes the first multicast group join request Multicast group force input request;

a second multicast protocol unit, configured to receive the second multicast group join request, and process the second multicast group join request;

The second multicast protocol proxy unit sends a third multicast group join request corresponding to the second multicast group join request after the second multicast protocol unit receives the second multicast group join request.

The multicast router according to claim 12, wherein the preset mode is a virtual interface mode, and the multicast router further includes:

And a virtual interface allocation unit, configured to allocate a virtual interface to the first multicast protocol proxy unit and the second multicast protocol unit in advance.