WO2008154796A1

WO2008154796A1 - A method and an equipment for controlling the transmission of the multicast data packets in the base station and the gateway of the wimax system

Info

Publication number: WO2008154796A1
Application number: PCT/CN2008/000936
Authority: WO
Inventors: Haibo Wen; Chunyan Yao
Original assignee: Alcatel Lucent
Priority date: 2007-06-15
Filing date: 2008-05-13
Publication date: 2008-12-24
Also published as: CN101325536A

Abstract

A transmission control method in the access service network for controlling the multicast data packets in the access service network gateway device of the WiMAX system, includes the steps: the multicast data packets to be transmitted is transmitted to the corresponding network link according to the multicast addresses and the multicast data forward table information of the multicast data packets to be transmitted, so as that the next one or more network devices receives the multicast data packets to be transmitted in the network link and forwards the multicast data packets until they are separately transmitted to the multiple base stations corresponding to the multicast addresses. A control method and corresponding equipment for controlling the data packets to be transmitted in the access service network in the base station of the WiMAX system are also provided. The network resource waste arose by that the same data packets are transmitted repeatedly in a network segment by using the GRE tunnel in the prior art is overcame.

Description

Base station and gateway control of WiMAX system

Method and device for transmitting multicast data packet

The present invention relates to a WiMAX system, and more particularly to a method and a corresponding apparatus for controlling multicast data packet transmission in a base station of a WiMAX system, and a method for controlling multicast data packet transmission in an access service network (ASN) gateway device of a WiMAX system And the corresponding device. Background technique

In recent years, wireless communication systems have developed rapidly, such as from personal mobile calls to commercial mobile offices. For different user markets, or for different technologies and market factors, there are many well-known wireless cellular communication standards on the market, such as GSM (Global System for Mobile Communications), UMTS (Universal Mobile Telecommunications System, Universal Mobile Telecomunication System ), WiMAX (World Interoperability for Microwave Access), etc. Among them, WiMAX adopts multi-carrier modulation technology, which can provide high-speed data services, and has the characteristics of high spectrum resource utilization, large coverage, high capacity under long distance, easy system upgrade, and effective service quality control. WiMAX is relatively inexpensive and can provide a wide range of multimedia communication services, such as convenience for individuals, homes, businesses, excellent mobile multimedia broadband services, and high-speed wireless data transmission. Compared with existing mobile communication technologies, WiMAX technology can provide higher data rates and stronger data service capabilities. Carrying streaming media services through WiMAX technology is a more economical and flexible means. Mobile streaming services on WiMAX networks will be a potential market for WiMAX technology applications.

At present, in the WiMAX system, a Generic Routing Encapsulation (GRE) tunnel is mainly used for data packet transmission. A GRE tunnel is a link between two points, and each link is a separate tunnel. A GRE tunnel is defined by the source IP address and the destination IP address of both ends, allowing the user terminal to encapsulate the IP using the IP packet. IPX and AppleTalk packages, and support a variety of routing protocols, such as RIP2, OSPF, etc. The tunnel established by the GRE is a virtual tunnel. It is only related to the tunnel source point and the tunnel end point. The intermediate nodes (such as routers) through which the packets pass are still forwarded by the ordinary route on the network according to the outer IP. For example, after tunneling the data packet to be tunneled (that is, adding a new packet header - the GRE packet header, which includes the tunnel destination address), the tunnel encapsulated data packet is sent, that is, placed in the tunnel. . When the packet encapsulated by the tunnel reaches the end of the tunnel, its GRE header is removed and continues to be addressed according to the destination address of the original message.

1 shows a schematic diagram of a protocol layer architecture for controlling data packet transmission in a WiMAX Access Service Network (ASN) according to the prior art. Since all data packets (including unicast data packets and multicast data packets) transmitted in the prior art WiMAX network are propagated in a tunnel (for example, GRE tunnel), that is, between the ASN gateway device 3 and the base station 1 ( That is, the R6 interface establishes a GRE tunnel, and then all the data packets are transmitted from the ASN gateway device 3 through the established GRE tunnel to the base station, for example, the GRE tunnel between the ASN gateway device 3 and the base station 14 shown in FIG. 2. It is understood by those skilled in the art that in the GRE tunnel mode, the data packet is still transmitted to the destination device through one or more network devices, for example, one of the GRE tunnels will pass through the router 22, the switch 25, and the switch 28 shown in FIG. A data packet is transmitted from the ASN gateway device 3 to the base station 14, and the transmission path through which the GRE tunnel is passed is usually fixed. Correspondingly, from the perspective of the protocol layer architecture shown in Figure 1, the transmission protocol between the ASN gateway device 3 and the base station 1 includes a GRE layer in addition to the conventional physical layer, link layer, and network layer. It can be understood that the GRE layer is specifically used to control the transmission of data packets through the above GRE tunnel. Similarly, those skilled in the art understand that the IP protocol is generally used to control data packets between the connection service network 9 and the ASN gateway device 3 (ie, the R3 interface), so the protocol layer between the two includes the physical layer and the link. Layer; and between the base station 1 and the mobile terminal 4 (ie, the R1 interface), the 802.16 protocol is used to control the data packet for transmission. This should be known to those skilled in the art and will not be described in detail herein.

The application of GRE tunneling technology in WiMAX systems brings a lot of convenience to the transmission of data packets, but there are also some shortcomings, such as the inability to consider related routing information and performance issues. And it is easy to form a situation in which data rebounds. These defects do not fully exploit the efficiency of routing. For example, the starting point of a GRE tunnel in a WiMAX system is often the same ASN gateway device, and the destination is often a different base station. According to the characteristics of the GRE tunnel, a data packet transmitted through the GRE tunnel needs to be transmitted from the source point of the GRE tunnel, that is, from the ASN gateway device to the next-level network device (such as a router or a switch) through the tunnel. It is then transmitted to the next level of network equipment (such as a router or switch), after passing through the multi-level network equipment until it is transmitted to the end of the GRE tunnel, that is, the destination base station. The packet seen by the intermediate node (router or switch) through which the tunnel passes is only a unicast packet (that is, the source/sink address it sees is only the IP address at both ends of the tunnel). In this process, packets transmitted through multiple different GRE tunnels may be the same one packet, and there may be some identical between the ASN gateway device and multiple different base stations (multiple different GRE tunnels). The transmission path, GRE tunnel transmission mode may cause the same data packet to be transmitted multiple times on the same transmission path. This causes waste of network resources and the use of routing information is also insufficient. For another example, when the sender of a data packet does not first pass through the ASN gateway device, but first passes through a network device (for example, router A) between the base station and the ASN gateway device, at this time, if it is transmitted through the GRE tunnel, Packets must first be transmitted "far" from the target base station to the tunnel source device (such as a gateway device) and then tunneled to the target base station from a more "far" network device. A data rebound has occurred. Those skilled in the art understand that it is extremely disadvantageous when the physical distance between the router A and the gateway device is relatively long.

Therefore, the application of the GRE tunnel to transmit data packets in the WiMAX system does not solve the transmission of multicast packets. It is necessary to propose a solution to overcome the above drawbacks. Summary of the invention

In the prior art, the application of the GRE tunneling multicast data packet in the WiMAX system may cause the same data to be transmitted multiple times in the same network segment and the data rebound. The purpose of the present invention is to access the WiMAX system. Multicast technology is used instead of tunnel technology to transmit multicast numbers based on GRE tunneling data packets in the service network. According to the packet, a multicast distribution tree is dynamically established between the base station and the ASN gateway device (ASN-GW), and the multicast data is forwarded hop by hop along the multicast distribution tree instead of being directly transmitted from the ASN-GW to the base station through the tunnel. .

According to an aspect of the present invention, a control method for controlling transmission of a data packet in an access service network in a base station of a WiMAX system is provided, comprising the steps of: L receiving a multicast join request message from a user terminal, for requesting to join a multicast; ii. providing a corresponding multicast data stream to the user terminal according to the multicast join request message.

According to another aspect of the present invention, there is provided a control apparatus for controlling transmission of a data packet in an access service network in a base station of a WiMAX system, and a base station including the control apparatus, the control apparatus comprising: a third receiving apparatus, Receiving a multicast join request message from the user terminal, where the multicast join request message is used to request to join a multicast; and the data stream processing apparatus is configured to provide, according to the multicast join request message, the user terminal Multicast data stream.

According to another aspect of the present invention, there is provided a control method for controlling transmission of a multicast data packet in an access service network in an access service network gateway device of a WiMAX system, comprising the steps of: according to a group of multicast data packets to be transmitted Broadcasting address and multicast data forwarding table information, sending the to-be-transmitted multicast data packet to a corresponding network link, so that one or more lower-level network devices on the network link receive the to-be-transmitted group Broadcasting the data packet and further forwarding the multicast data packet to be transmitted until respectively transmitted to a plurality of destination base stations related to the multicast group (ie, finally transmitted to the base station joining the multicast group).

According to still another aspect of the present invention, a control apparatus for controlling multicast packet transmission in an access service network gateway device of a WiMAX system and an access service network gateway device including the control apparatus are provided, the control apparatus including the first a sending device, configured to send the multicast data packet to be transmitted to a corresponding network link according to the multicast address of the multicast data packet to be transmitted and the multicast data forwarding table information, so that one of the network links Or the plurality of lower-level network devices receive the multicast data packet to be transmitted and further forward the multicast data packet to be transmitted until respectively transmitted to the plurality of target base stations corresponding to the multicast address.

Preferably, the control device in the gateway device further includes: a first receiving device, Receiving a data packet to be transmitted; a first determining means, configured to determine whether the data packet to be transmitted is a multicast data packet; and acquiring means, configured to: when the data packet to be transmitted is a multicast data packet Obtaining the multicast data forwarding table information corresponding thereto.

Through the invention, the multicast data packets transmitted in the access service network of the WiMAX system are transmitted in a multicast manner, which overcomes the prior art that the GRE tunnel is used for transmission, and the same data packet is repeatedly transmitted in one network segment. The resulting network resources are wasted. DRAWINGS

Other features, objects, and advantages of the present invention will become more apparent from the Detailed Description of Description

1 is a schematic diagram showing a protocol layer architecture for controlling data packet transmission in a WiMAX access service network according to the prior art;

2 is a schematic diagram of a WiMAX access service network according to an embodiment of the present invention, including a multicast distribution tree for multicast packet forwarding, where it is assumed that all base stations have receivers of the multicast group;

3 is a flow chart showing a method for controlling multicast data packets to be transmitted in a WiMAX access service network in an ASN gateway device of a WiMAX network according to a first embodiment of the present invention;

4 shows a specific flow of step S15 shown in FIG. 3 according to the first embodiment of the present invention, that is, the multicast data packet to be transmitted is transmitted to multiple base stations as multicast members according to the multicast data forwarding table information. Flow chart

5 is a flow chart showing establishing or updating the multicast data forwarding table in an ASN gateway device of a WiMAX network according to a first embodiment of the present invention;

6 is a flowchart showing a control method for controlling transmission of a multicast packet in an access service network in a base station of a WiMAX network according to a first embodiment of the present invention; FIG. 7 shows a method according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A schematic diagram of a protocol layer architecture for controlling multicast data packets for transmission in an access service network of a WiMAX network; FIG. 8 shows an ASN gateway device in a WiMAX network according to a first embodiment of the present invention. Control device for controlling the transmission of multicast packets in a WiMAX network a schematic diagram of the composition of 7;

Figure 9 is a diagram showing the composition of a control device 8 for controlling the transmission of multicast data packets in an access service network of a WiMAX network in a base station of a WiMAX network in accordance with a first embodiment of the present invention.

detailed description

The invention will be described in detail below with reference to the accompanying drawings:

Figure 2 also shows a schematic diagram of a multicast distribution tree for transmitting multicast data packets over a WiMAX network in accordance with an embodiment of the present invention. In this embodiment, different transmissions are performed in the GRE tunnel encapsulation manner in the WiMAX network in the WiMAX network. In the present invention, for a specific multicast service, the first The requirement is to establish a tree-like multicast structure (that is, a multicast distribution tree) starting from the root node according to the group member management protocol and the multicast routing protocol, such as the gateway device 3 (ie, the root node) shown in FIG. Routers 21 and 23 → routers 24, 25 → switches 26, 27 and 28 → base station 11-14 multicast distribution trees. Here, it is assumed that a plurality of base stations 11-14 are multicast members of this particular multicast group (ie, Corresponding to the mobile station receiving the corresponding multicast group under the base station, the multicast data stream transmitted by the multicast source through the multicast distribution tree is received. Of course, for a specific multicast group, the multicast distribution tree may only extend to some base stations (that is, the mobile station receives data of the multicast group under the base station). For the unicast service, it can still be transmitted through a GRE tunnel (for example, the tunnel 61 shown in FIG. 2) between the ASN gateway device 3 and the corresponding base station.

Those skilled in the art should understand that in practical applications, the network architecture shown in FIG. 2 may be more complicated, for example, there may be multiple gateway devices, switches, routers, etc., and the like, but this does not affect the present invention. The substance is not described in detail here. In FIG. 2, the ASN gateway device 3 is used to connect a core network (e.g., a connection service network, CSN) and an access service network; base stations 11 to 14 and the like are connected to the mobile terminal 41 44 via a wireless network. Specifically, those skilled in the art understand that the base station can directly transmit data with the mobile terminal 41, and can also transmit data through the relay station 45 and the mobile terminal 44, which is the field. Those skilled in the art will not be described here.

In the following, with reference to FIG. 2, a method for controlling multicast data packet transmission in a WiMAX access service network according to an embodiment of the present invention is described in detail. With the control method and apparatus provided by the present invention, a group can be made. The broadcast data packet is transmitted to multiple base stations along the multicast distribution tree without using a GRE tunnel for transmission, so that such data packets are transmitted only once in the same network segment, which reduces data traffic in the network and improves transmission. effectiveness.

Specifically, in a multicast group formation process, each node or network device (for example, a router or a switch) in the multicast distribution tree establishes a corresponding local multicast data forwarding table, and the local multicast data is transferred. The publication should include information about multicast forwarding, such as a multicast address (or multicast group address) and one or more downstream interfaces that should pass the multicast stream, which are respectively connected to a network link. Also, in multicast During the group survival process, each level of network equipment will continuously update its local multicast data forwarding table according to the joining or exiting of multicast members.

When the multicast service is transmitted, the root node starts, and each network device receives the multicast data packet from the upper-level network device by the uplink interface, and checks whether the multicast address included in the network packet belongs to the group. Broadcast the data packet to determine whether it should be received; after receiving the correct multicast data packet, the relevant multicast data can be obtained from the multicast data forwarding table according to the multicast address in the multicast data packet. Forwarding table; subsequently, the network device uses the multicast address and the forwarding related information in the maintained multicast data forwarding table to determine a downlink interface corresponding to the multicast data packet, and the multicast interface is sent through the downlink interface The data packets are passed out, which should be well known to those skilled in the art and will not be described here.

If a new network device requests to join the multicast group, it can send a multicast join request based on a specific multicast management protocol, thereby joining a multicast distribution tree to become a multicast member, and the corresponding multicast data will be along The multicast distribution tree is passed to each multicast member. The specific multicast management protocol includes an IPv4-based IGMP protocol (Group Member Management Protocol) and an IPv6-based MLD protocol (Multicast Listening and Discovery Protocol), which should be known to those skilled in the art, and will not be described herein. Specifically, in the process of establishing and joining the multicast tree, a non-group The broadcast member receives a multicast join request message from its next-level network device, and extracts corresponding multicast information (for example, a multicast address) from the request message, and retrieves the multicast data forwarding table maintained by the broadcast message. If the multicast information is not included, the downlink interface that receives the multicast join request is stored in the multicast data forwarding table in association with the multicast related information (for example, a multicast address). The multicast join request message that adds the request to the multicast is forwarded to the upper-level network device according to the multicast routing protocol, and the upper-level or multiple network devices upload the multicast join request in a similar manner. Up to a multicast member closest to the multicast distribution tree; and when the multicast member receives a multicast join request from a new member of the next level, the multicast data forwarding table includes the multicast Related information (for example, a multicast address and a downlink interface connected to one or more multicast members of the next level), it is not necessary to forward the multicast join request message upward, but only The downlink interface information received by the multicast join request is recorded in the multicast data forwarding table in association with the multicast address, thereby implementing establishment and update of the multicast data forwarding table, which is well known to those skilled in the art. It will not be repeated here.

In the GRE tunnel transmission mode in the prior art, data packets from any intermediate node or network device must be sent to the corresponding base station through the GRE tunnel through the ASN gateway. Otherwise, the multicast data packet in the present invention adopts a pure group. The broadcast mode is transmitted. The root node of the multicast distribution tree can be any intermediate node between the ASN gateway or the ASN gateway and the base station. When the root node is any intermediate node between the ASN gateway and the base station, the multicast data stream can be directly The multicast distribution tree is transmitted without going through the ASN gateway, and there is no multiple multicast packet transmission in each network segment, thereby greatly saving network resources. The base station receives the multicast data. After the packet, the multicast data packet is sent to the mobile terminal or the relay station requesting to join the multicast group via the air interface according to the forwarding related information established internally, which is well known to those skilled in the art, and is not the focus of the present invention. The content of the description is not described in detail here.

Figure 3 is a flow diagram showing a method for controlling the transmission of multicast packets in a WiMAX network in an ASN gateway device of a WiMAX network in accordance with a first embodiment of the present invention. This embodiment is applied to the ASN gateway device 3 in the WiMAX network.

As described above, in the present invention, when performing multicast service transmission, the multicast distribution tree Below the root node, it can be any intermediate node between the ASN gateway or the ASN gateway and the base station. When the ASN gateway device acts as a root node or other intermediate node, it needs to control the transmission of the multicast data packet in a multicast manner. The following will refer to FIG. 3 and related to FIG. 2 for the ASN gateway device according to the present invention. A method for controlling the transmission of multicast packets is described in detail:

First, step S11 is performed to receive a data packet to be transmitted from a multicast source or a core network (for example, a connection service network). Those skilled in the art should understand that the data packet may come from a variety of devices, for example, a base station may send a service request to a core network (such as a connection service network) (for example, a request to send a WAP web page to a mobile terminal), at this time, The core network returns the WAP web page to the base station. A data packet including the content of the WAP webpage is sent to the base station through an R3 interface between the core network and the ASN gateway device 3, and the data packet is sent by the corresponding base station to the mobile terminal requesting the WAP webpage. This should be well known to those skilled in the art and is not essential to the invention and will not be described in detail herein.

Then, proceeding to step S12, it is determined whether the data packet to be transmitted is a multicast data packet that the ASN gateway device should receive. It should be understood by those skilled in the art that the determining step of step S12 is optional. For example, when the ASN gateway device is connected to only one multicast service, no judgment is needed, and the determining step can be implemented in the following manner: For example, in this embodiment Determining whether the data packet to be transmitted is a multicast data packet by determining whether the data packet includes a related multicast address included in the multicast data forwarding table, and if the related multicast address is included, determining that the data packet is The multicast packet should be received, and conversely, no reception is required, which should be well known to those skilled in the art and will not be mentioned here.

If the result of the step S12 is affirmative, that is, the data packet to be transmitted is a multicast data packet, step S14 is performed, and then the process proceeds to step S15; if the determination result of the step S12 is negative, the If the transport data packet is a unicast data packet, step S13 is performed, and the data packet is transmitted to the destination network device by using a GRE tunnel (that is, after GRE tunnel encapsulation of the data packet) in a unicast manner, where the target network is The device is usually a base station. Those skilled in the art understand that the step S13 can be implemented by referring to the prior art of the WiMAX network, for example, according to each network device corresponding to the GRE tunnel (for example, the GRE tunnel 61 in FIG. 2 via the ASN gateway device 3 → router 23 → switch 25) →Cross The switch 25 → base station 14 is configured to transmit the data packet to the base station, and the GRE tunnel makes the base station and the ASN gateway device logically directly connected, and will not be described in detail herein.

In step S14, the multicast forwarding related information corresponding to the to-be-transmitted data packet is obtained according to the multicast related information (for example, a multicast address) in the received multicast data packet, usually, in the ASN gateway device. 3 A multicast data forwarding table should be maintained, which contains multiple multicast addresses and corresponding forwarding related information (for example, the downstream interface or outbound interface of the multicast stream should be delivered, which is connected to a network link). Therefore, in this embodiment, the multicast data forwarding table can be used to query forwarding related information corresponding to the multicast address in the multicast data packet.

In step S15, the multicast data packet to be transmitted is sent to the corresponding network link according to the multicast data forwarding table information, so that one or more lower-level network devices on the network link receive the The multicast data packet to be transmitted is further forwarded to the plurality of destination base stations corresponding to the multicast address, that is, multiple base stations that are multicast members.

The ASN gateway device will also update the locally maintained multicast data forwarding table according to the received multicast join request message from the new multicast member or the multicast exit request message from the existing multicast member. The contents described above with reference to FIG. 2 are described in detail and will not be described herein. Figure 4 shows a specific flow chart of step S15 shown in Figure 3 in accordance with a first embodiment of the present invention. Specifically, the step S15 shown in FIG. 3 may be implemented as follows: According to the multicast address of the multicast data packet to be transmitted and the multicast data forwarding table information, the multicast to be transmitted A data packet is sent to the network link through an interface of the gateway device connected to the access service network. Those skilled in the art understand that the ASN gateway device 3 can be connected to multiple different network links through different downlink interfaces, different network devices may be connected to different network links, and one network device may be connected to several different networks. Network link. In such a variation, by performing step S151, the ASN gateway device 3 may determine, according to the multicast address of the multicast data packet and the corresponding multicast forwarding related information, that the gateway device 3 corresponds to the multicast data packet. Downlink And then proceeds to step S152, and the multicast data packet is sent to the network link through the downlink interface. This is a common knowledge of those skilled in the art and will not be described herein.

Specifically, those skilled in the art understand that the ASN gateway device 3, as the root node or other intermediate nodes of the multicast distribution tree, can send a request for acquisition to other network devices in addition to maintaining a multicast data forwarding table locally. The query request message (or the group membership query request message) of the multicast data forwarding related information, for example, sending a query request to the other device by using the multicast address included in the multicast data packet as a key to obtain the query request Multicast data forwarding related information related to the broadcast address (for example, downlink interface information related to the multicast service). Those skilled in the art can implement this according to the prior art, and details are not described herein.

After receiving a multicast data packet, the router 21 or the router 23 can determine, according to the multicast packet forwarding table that it maintains, which downlink interface should be sent to the next-level network device. For example, after querying the multicast data forwarding table, the router 23 determines that the multicast data packet should be forwarded through the downlink interface to which the switch 25 is connected. The multicast packet is passed through the multicast distribution tree shown in Figure 2 in stages in the same manner up to base stations 13 and 14.

Referring to FIG. 3 and FIG. 4, those skilled in the art understand that in the foregoing step S15 and/or step S152, the next-level network device that receives the transmitted multicast data packet through the network link may be a router. Switch or base station. This is understood and implemented by those skilled in the art according to the prior art and will not be described in detail herein. Figure 5 is a flow chart showing the establishment or update of the multicast data forwarding table information in an ASN gateway device of a WiMAX network, in accordance with a first embodiment of the present invention.

The process of establishing or updating multicast forwarding related information (or multicast data forwarding table) in the ASN gateway device according to the present invention will be described in detail below with reference to FIG. 5 in conjunction with FIG. 2:

In step S151, a multicast join request message sent from the network device (e.g., base station, router or switch) in the ASN network to the ASN gateway is received.

Going to step S152, establishing or updating the group according to the multicast join request message Broadcast data forwarding table. Specifically, as described above, after receiving the multicast join request message from a network device, the ASN gateway device extracts corresponding multicast related information (for example, a multicast address) and retrieves the multicast data maintained by the ASN gateway device. If the multicast related information is not included, the downlink interface that receives the multicast join request is stored in the multicast data forwarding table in association with the multicast related information (for example, a multicast address). As a new multicast data forwarding entry; if it finds that the multicast related information is included in the multicast data forwarding table (for example, the multicast address and the downlink connected to one or more multicast members of the next level) The interface or the like adds only the downlink interface information that has received the multicast join request to the multicast data forwarding table in association with the multicast address.

Similarly, if a multicast exit request message is received from a network device that is an existing multicast member, the ASN gateway device removes the forwarding related information related to the existing multicast member from the multicast data forwarding table it maintains. Information (not shown).

By performing the above steps, the ASN gateway can implement the establishment and update process of the multicast data forwarding table. Figure 6 is a flow chart showing a control method for controlling transmission of data packets in a WiMAX network in a base station of a WiMAX network in accordance with a first embodiment of the present invention. This procedure applies to base stations in a WiMAX network. According to the present invention, the base station needs to perform the following processing steps for different situations when transmitting the multicast service:

First, if the base station itself has joined the requested multicast group, the base station directly forwards the corresponding multicast data stream to the next-level network device;

Second, if the base station itself has not joined the requested multicast group, the base station will request to join the multicast group, that is, requesting to join the multicast group by sending a multicast join request message to the upper-level network device. The process is directly related to the embodiment shown in Figure 5 above.

The flow in the base station will be specifically described below with reference to Figs. 2 to 5 and in conjunction with Fig. 6.

Specifically, step S21 is first performed to receive a request message from the next-level network device requesting to join a multicast group. Those skilled in the art understand that the next-level network device may be a relay station (SS) or a mobile station or a mobile terminal (MS), and the two types of lower-level network devices may be in the same manner. Processing, this The substance of the invention is not affected and will not be described in detail herein. Those skilled in the art should also understand that the multicast join request message can adopt different forms of message formats, for example, based on

In the IPv4 protocol network, the multicast join request message may be an IGMP (Internet Group Management Protocol) message, and in the IPv6 protocol-based network, the multicast join request message may be an MLD (Multicast Listening Discovery Protocol). Message.

After step S21, the process proceeds to step S22, where it is determined whether the multicast data stream has been delivered. The determination of this step is because the processing manner is different if the base station has joined the multicast group and starts to deliver the multicast data stream to other user terminals, and the base station itself has not joined the multicast group. .

Specifically, if the result of the step S22 is affirmative, that is, the base station has joined the requested multicast group and starts to deliver the multicast stream to other user terminals, step S23 is performed to join the user terminal to the multicast. The multicast member of the group and the multicast data stream are delivered to the user terminal; otherwise, if the result of the step S22 is negative, step S24 is performed, and the source address information in the request message is replaced with Describe the address information of the base station, thereby obtaining a new request message; and then performing step S25 to send the new request message to the upper-level network device.

It should be understood by those skilled in the art that, in different situations, the network device in step S23 may be a different device. For example, in one embodiment, the network device is a switch, such as shown in FIG. 2, The base station is directly connected to a switch; in a variant, the network device is a router, for example, when the base station is directly connected to a router; in a variant, the network device is a gateway device, for example, the base station is directly connected to one In the case of a gateway device. This is a common knowledge of those skilled in the art, and is not a focus of the present invention and will not be described in detail herein.

In addition, it should be noted that step S24 is mainly applicable to the execution of an ingress filter in each network device (such as a router, a switch, and a gateway device) of the WiMAX network. In this case, the R6 interface shown in FIG. The source address of each packet passing through the R6 interface is detected, and the source address packets not belonging to the network are discarded. In actual applications, the address used by the intermediate node such as the base station and the address of the user terminal may belong to different network address spaces. If the source address information is not replaced by the base address in the above step S24, The address information of the station may cause such a multicast join request message to be discarded. Therefore, usually the step S24 is necessary. However, in a variation of the embodiment shown in Fig. 6, the step S24 may be omitted, and such a variation is more suitable for the case where the entrance detection is not performed.

In step S25, the base station forwards the new multicast join request message to the upper-level network device according to the multicast management protocol. The upper-level network device extracts the requested multicast-related information (for example, a multicast address) from the new multicast join request message, and determines whether it is the multicast according to the maintained multicast data forwarding table. a multicast member of the group, if the base station has not joined the multicast group, the related information of the multicast join request message is recorded in the multicast data forwarding table (for example, the multicast address and the multicast join request message is received) The downlink interface is used as the multicast forwarding related information, and the multicast join request message is further forwarded to the upper-level network device based on the multicast management protocol, and the above-mentioned first-level or multi-level network devices are stepped in a similar manner. Forwarding the multicast join request until reaching a multicast member closest to the multicast group, the closest multicast member being the network device between the ASN gateway device or the ASN gateway device and the base station, the group If the broadcast is negative, only the related information of the received multicast join request message is added to the locally maintained multicast data forwarding table, and the multicast join is not required to be forwarded. Request message, the multicast base station to complete the joining process.

After the base station joins the multicast tree directly or via the multi-level network device; the multicast data stream from the multicast source is multicasted to each multicast member including the base station via the multicast distribution tree.

The process of processing the multicast exit request message from the next-level network device by the base station will be described below with reference to FIG. 6 and related to FIG. 2 . Specifically, the base station receives an exit multicast group request message from the user terminal, which is used to request to quit a multicast group. Then, the base station determines, according to the exit multicast group request message, whether the base station is still The user other than the user who quits the multicast group request message provides the multicast data stream corresponding to the multicast group, because if the next-level network device of the base station does not need the multicast group, the base station itself does not need It then exists in the multicast group. Therefore, if the base station further provides the multicast data stream corresponding to the multicast group for the user other than the user who sends the multicast group request message, the base station deletes the multicast data forwarding table maintained by the base station. In addition to the multicast forwarding related information of the user, the multicast data stream is not provided to the user terminal requesting to quit the multicast group, but the multicast data is still provided to other user terminals that need the multicast. Conversely, if the base station does not provide the multicast data stream corresponding to the multicast group for the user other than the user who sends the multicast group request message, the multicast data maintained by the base station is transferred. In the publication, the related information of the user is deleted, and the exiting multicast group request message is sent to the upper-level network device, and the exiting multicast group request message is sent by the upper-level network device, so that the base station itself also exits the multicast. group. A specific process of the base station to exit the multicast group may be implemented by a person skilled in the art with reference to the prior art and the foregoing description, and is not described in detail herein.

In the above process of requesting the user terminal to quit a multicast group, similar to the figure

Step 6: Step S24, the base station may replace the source address information in the exit multicast request message with the address information of the base station, thereby obtaining a new exit multicast group request message, and then the new The exit multicast group request message is sent to the upper-level network device. Those skilled in the art will also appreciate that such processing is preferably applicable to the case of ingress detection at the R6 interface, and will not be described in detail herein. 7 shows a schematic diagram of a protocol layer architecture for controlling multicast data packets for transmission in an ASN network of WiMAX, in accordance with an embodiment of the present invention. Referring to FIG. 2, and in conjunction with the protocol layer architecture provided by this embodiment, those skilled in the art can further understand the difference between the present invention and the prior art. In this embodiment, the ASN gateway device 3 and the connection service network 9 are still transmitted by using an IP protocol, except that in the case of processing a multicast data packet that needs to be transmitted to multiple base stations, the ASN is The gateway device 3 and the connection service network 9 are no longer transmitted through the GRE tunnel mode, but are directly transmitted by using the IP protocol-based multicast mode. As described above, such a way that the same multicast packet does not need to be transmitted multiple times in the same network segment, saving network resources. The description of the above FIG. 1 to FIG. 6 will be understood by those skilled in the art, and will not be described in detail herein. Figure 8 shows an ASN in a WiMAX network in accordance with a first embodiment of the present invention. A block diagram of a control device 7 in a gateway device for controlling the transmission of multicast data packets over a WiMAX network. As shown in FIG. 8, the control device 7 includes a first receiving device 71, a first determining device 72, an obtaining device 73, and a first transmitting device 74.

As described above, in the present invention, when performing multicast service transmission, under the root node of the multicast distribution tree, it may be any intermediate node (for example, a router) between the ASN gateway or the ASN gateway and the base station. When ASN The gateway device acts as a root node or other intermediate node, which needs to control the transmission of the multicast data packet in a multicast manner. The control in the ASN gateway device according to the present invention will be described below with reference to FIG. 8 in conjunction with FIG. 2 and related content. The control device for the transmission of multicast packets is described in detail:

Specifically, the first receiving device 71 receives the data packet to be transmitted. Those skilled in the art understand that the data packet may come from a variety of devices, for example, a base station may send a service request to the core network (such as a connection service network) (for example, a request to send a WAP web page to the mobile terminal), at this time, The core network returns the WAP web page to the base station. Therefore, the data packet including the content of the WAP webpage is sent to the base station through the R3 interface between the core network and the ASN gateway device 3, and the data packet is sent by the corresponding base station to the mobile terminal requesting the WAP webpage. This should be well known to those skilled in the art and is not essential to the invention and will not be described in detail herein.

The first determining means 72 determines whether the data packet to be transmitted is a multicast data packet. It should be understood by those skilled in the art that those skilled in the art should understand that the first determining device 72 is not necessary, for example, when the ASN gateway device only connects one multicast service, no judgment is needed, and the first determining device 72 can pass multiple The method for implementing the determining process, for example, in the embodiment, determining whether the data packet to be transmitted is a multicast data packet by determining whether the data packet includes a related multicast address included in the multicast data forwarding table, if included The related multicast address determines that the data packet should receive the multicast data packet, and vice versa, and does not need to be received. In a variant, it can also be implemented by other means, which is common knowledge of those skilled in the art. Do not repeat them.

If the judgment result of the first judging device 72 is affirmative, that is, the data packet to be transmitted is a multicast data packet, the first transmitting device 74 will transmit the multicast data packet to be transmitted in a multicast manner. Specifically, when the first receiving device 71 receives the multicast data packet, the obtaining device 73 acquires the data packet to be transmitted according to the multicast related information (for example, a multicast address) in the received multicast data packet. Corresponding multicast packet forwarding related information. Those skilled in the art should understand that one ASN gateway device 3 can be connected to multiple different network links through different downlink interfaces, and multiple different network devices may be connected to one or more different network links, and one Network devices may connect to several different network links. Generally, the ASN gateway device 3 includes a multicast data forwarding table that includes multiple multicast addresses and corresponding forwarding related information (for example, a downlink interface or an outgoing interface that should transmit the multicast stream, Connect to a network link). Therefore, in this embodiment, the multicast data forwarding table can query the forwarding related information corresponding to the multicast address included in the multicast data packet.

The first sending device 74 sends the multicast data packet to be transmitted according to the multicast data forwarding table information to a network link connected to the downlink interface, so that one or more next level on the network link The network device receives the multicast data packet to be transmitted and further forwards the multicast data packet to be transmitted until it is respectively transmitted to multiple target base stations corresponding to the multicast address, that is, multiple base stations that are multicast members.

Specifically, the first sending device 74 further includes a determining device (not shown) and a third transmitting device (not shown), wherein the determining device can be based on the multicast address of the multicast data packet and the corresponding multicast data. The forwarding table information may determine a downlink interface of the gateway device 3 corresponding to the multicast data packet; then, the third sending device sends the multicast data packet to the network link through the downlink interface. This is a common knowledge of those skilled in the art and will not be described herein.

It is understood by those skilled in the art that, in addition to the query by the multicast data forwarding table maintained by the ASN gateway device, the obtaining device 73 may also send a query request to other devices to obtain the multicast forwarding related information corresponding to the multicast service. (ie, a downlink interface for delivering the multicast data stream, the downlink interface is connected to a network link). In this variant, the obtaining means 73 may query the multicast data forwarding table by using the multicast address included in the multicast data packet to obtain the corresponding information of the downlink interface. This can be achieved by those skilled in the art according to the prior art, and details are not described herein. Referring to FIG. 2, after receiving a multicast data packet, the router 21 or the router 23 can determine, according to the multicast data forwarding table managed by the router 21 or the router 23, which downlink interface should be sent to the downlink interface. The next level network device, for example, the router 23 queries the multicast data forwarding table and determines that the data packet should be forwarded through the downlink interface to which the switch 25 is connected. The multicast packet is passed through the multicast distribution tree shown in Figure 2 in stages in the same manner up to the base stations 13 and 14. Those skilled in the art understand that the next level network device that receives the transmitted multicast data packet through the network link may be a router, a switch or a base station. This is understood and implemented by those skilled in the art according to the prior art and will not be described in detail herein.

In a preferred embodiment, the control device 7 of the ASN gateway device may further include a second transmitting device 75, as shown in FIG. 8. Specifically, when the first determining device 72 determines that the received data packet to be transmitted is unicast data. Packet, the second transmitting device 75 will transmit the unicast data packet to be transmitted in a unicast manner, that is, use the GRE tunnel (that is, after GRE tunnel encapsulation of the data packet) to transmit the data packet to the destination network. The device, the target network device is typically, for example, a base station. It should be understood by those skilled in the art that the unicast transmission process of the second transmitting device 74 can be implemented by referring to the prior art of the WiMAX network, for example, according to each network device corresponding to the GRE tunnel (for example, the GRE tunnel 61 in FIG. 2 via the ASN gateway device). 3→Router 23→Switch 25→Switch 25→Node 14 is configured to transmit the data packet to the base station. Logically, the GRE tunnel directly connects the base station to the ASN gateway device, which is not described in detail herein.

In another preferred embodiment, the control device 7 of the ASN gateway device may further comprise a second receiving device 76 and a routing maintenance device 77 for receiving and/or coming from the received multicast join request message from the new multicast member. The multicast exit request message of the original multicast member is used to update the locally maintained multicast data forwarding table. Specifically, after the second receiving device 76 receives the multicast join request message from a network device, the multicast maintenance device 77 retrieves corresponding multicast related information (for example, a multicast address) from the retrieved The multicast data forwarding table, if it is found that the multicast related information is not included, the downlink interface that receives the multicast join request is stored in association with the multicast related information (for example, a multicast address). Multicast data forwarding table as a new multicast data forwarding table If it finds that the multicast related information is included in the multicast data forwarding table (for example, the multicast address and the downlink interface connected to one or more multicast members of the next level), it will only receive The downlink interface information of the multicast join request is added to the multicast data forwarding table in association with the multicast address. Similarly, when the second receiving device 76 receives the multicast quit request message from the network device that is an existing multicast member, the multicast maintenance device 77 removes the multicast data forwarding table from the multicast forwarding table it maintains. There are forwarding related information related to multicast members (not shown in the figure). Therefore, the multicast maintenance device 77 can implement the process of establishing and updating the local multicast data forwarding table. 9 is a diagram showing the composition of a control device 8 for controlling multicast data packets to be transmitted in an access service network of a WiMAX network in a base station of a WiMAX network according to a first embodiment of the present invention.

A control device for controlling multicast packet transmission in a base station according to the present invention will be described in detail below with reference to FIG. 9 in conjunction with FIG. 2:

In the present embodiment, the control device 8 includes a third receiving device 81 and a data stream processing device 82. Specifically, the third receiving device 81 is configured to receive a multicast join request message from the user terminal, where the multicast join request message is used to request to join a multicast. . A person skilled in the art should also understand that the multicast join request message may adopt different forms of message formats. For example, in an IPv4 protocol-based network, the multicast join request message may be an IGMP (Internet Group Management Protocol) message. In the IPv6-based network, the multicast join request message may be an MLD (Multicast Listening Discovery Protocol) message.

The data stream processing device 82 provides a corresponding multicast data stream to the user terminal according to the multicast join request message.

Specifically, in the embodiment, the data stream processing device 82 further includes a second determining device 821, a first processing device 822, and a second processing device 823. The second determining means 821 is configured to determine, according to the multicast join request message, whether the multicast data stream requested by the user terminal has been provided to the user terminal; the first processing device 822 is configured to When the user terminal provides the multicast data stream requested by the user terminal, the multicast join request message is sent to the upper-level network device. The second processing device 823 is configured to be used When the user terminal provides the multicast data stream requested by the user terminal, the user terminal is added to the multicast multicast member and the multicast data stream is delivered to the user terminal. The second determining device 821 determines whether the base station itself has joined the requested multicast group. If the base station itself has joined the requested multicast group, the base station directly forwards the corresponding multicast to the next-level network device. The data stream; on the contrary, the base station needs to join the multicast group by adding a multicast join request message to the upper-level network device to join a multicast distribution tree.

In a variant, the first processing means 822 further comprises a first updating means (not shown) for replacing the multicast join request source address information with the address information of the base station, thereby obtaining a a new multicast join request message; and a fourth transmitting device (not shown in FIG. 10) that transmits the new multicast join request message to the upper level network device. Specifically, such a variation is mainly applicable to the case of an ingress filter. In this case, the packet source address of each packet passing through the R6 interface is detected at the R6 interface described above, and will not be The source address packets belonging to the network are discarded. In practical applications, the address used by the intermediate node such as the base station may belong to a different address space than the address of the user terminal. If the source address information is not replaced by the address information of the base station by the first update device, the The multicast join request message is discarded.

In a preferred embodiment, the control device 8 shown in Fig. 9 further includes a fourth receiving device 83, a third determining device 84, a third processing device 85, and a fourth processing device 86.

The fourth receiving device 83 receives an exit multicast group request message from the user terminal, where the exit multicast group request message is used to request to exit a multicast group;

The third determining device 84 determines, according to the exiting the multicast group request message, whether the base station further provides the multicast data stream corresponding to the multicast group for the user other than the user who sends the outgoing multicast group request message. This is because if the next-level network device of the base station does not need the multicast group, the base station itself does not need to exist in the multicast group again;

The third processing device 85, when the base station further provides the multicast data stream corresponding to the multicast group for the user other than the user who sends the multicast group request message, the multicast data maintained by the base station is transferred. In the publication, the related information of the user terminal is deleted. At this time, the multicast data stream is not provided to the user terminal requesting to quit the multicast group, but the multicast data is still provided to other user terminals that need the multicast. flow; The fourth processing device 86, when the base station no longer provides the multicast data stream corresponding to the multicast group for the user terminal other than the user that sends the multicast group request message, the group maintained by the base station Deleting the information about the user terminal in the broadcast data forwarding table, and sending the exit multicast group request message to the upper-level network device, and sending the exit multicast group request message to the upper-level network device, so that the base station itself also exits. The multicast group.

In another variation, the fourth processing device includes: a second update device (not shown), configured to replace source address information in the exit multicast request message with address information of the base station, Thereby obtaining a new exit multicast group request message; and a sixth transmitting means (not shown) for transmitting the new exit multicast group request message to the upper level network device. Similar to the first update device in the above-described variation of FIG. 10, the second update device is preferably applied to the case where the port detection is performed at the R6 interface, and details are not described herein. The specific embodiments of the present invention have been described above. It is to be understood that the invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the appended claims.

Claims

A control method for controlling transmission of a data packet in an access service network in a base station of a WiMAX system, comprising the following steps:

1. Receiving a multicast join request message from a user terminal, which is used to request to join a multicast;

Ii. providing the user terminal with a corresponding multicast data stream according to the multicast join request message.

The method according to claim 1, wherein the step ii further comprises the following steps:

111. Determine, according to the multicast join request message, whether the multicast data stream requested by the user terminal is provided to other user terminals;

112. If the multicast data stream requested by the user terminal has not been sent to another user terminal, the multicast join request message is sent to the upper-level network device according to the multicast management protocol.

The method according to claim 2, wherein the step U2 comprises the steps of: - replacing the multicast join request source address information with the address information of the base station, thereby obtaining a new multicast join request. Message

- Sending the new multicast join request message to the upper level network device according to the multicast management protocol.

The method according to claim 2 or 3, wherein the step ii further comprises the following steps:

- If the multicast data stream requested by the user terminal has been provided to other user terminals, the user terminal is added to the multicast multicast member and the multicast data stream is delivered to the user terminal.

The method according to any one of claims 1 to 4, further comprising the steps of:

- receiving an exit multicast group request message from the user terminal, which is used to request to exit a multicast group; Determining, according to the exiting the multicast group request message, whether the base station further provides the multicast data stream corresponding to the multicast group to another user terminal other than the user terminal that sends the exiting multicast group request message;

- if the base station further provides the multicast data stream corresponding to the multicast group to the other user terminal, deleting the user that issues the exit multicast group request message from the multicast data forwarding table maintained by the base station Information about the terminal;

- if the base station only provides the multicast data stream corresponding to the multicast group to the other user terminal, deleting the user that issues the exit multicast group request message from the multicast data forwarding table maintained by the base station The information about the terminal is sent to the upper-level network device according to the multicast management protocol.

The method according to claim 5, wherein the step of sending the exiting multicast group request message to the upper-level network device comprises the following steps:

- replacing the source address information in the exit multicast request message with the address information of the base station, thereby obtaining a new exit multicast group request message;

- transmitting the new exit multicast group request message to the upper level network device according to the multicast management protocol.

The method according to any one of claims 2 to 6, wherein the network device comprises any one of the following: a router, a switch, and a gateway device.

The method according to any one of claims 2 to 7, wherein the multicast management protocol comprises an IPv4 multicast management protocol, the multicast join request message and/or the exit multicast group request message. Includes IGMP messages.

The method according to any one of claims 2 to 7, wherein the multicast management protocol comprises an IPv6 multicast management protocol, the multicast join request message and/or an exit multicast group request message. Includes MLD messages.

10. A control device for controlling transmission of data packets in an access service network in a base station of a WiMAX system, wherein:

a third receiving device, configured to receive a multicast join request message from the user terminal, where the multicast join request message is used to request to join a multicast group;

a data stream processing apparatus, configured to use, according to the multicast join request message, the user The terminal provides a corresponding multicast data stream.

The control device according to claim 10, wherein the data stream processing device comprises:

a second determining device, configured to determine, according to the multicast join request message, whether the multicast data stream requested by the user terminal has been sent to another user terminal;

The first processing device is configured to send the multicast join request message to the upper-level network device according to the multicast management protocol when the multicast data stream requested by the user terminal has not been provided to the other user terminal.

The control device according to claim 11, wherein the first processing device further comprises:

a first updating means, configured to replace the multicast join request source address information with the address information of the base station, to obtain a new multicast join request message;

And a fifth sending device, configured to send the new multicast join request message to the upper-level network device according to the multicast management protocol.

The control device according to claim 11 or 12, wherein the data stream processing device further comprises:

The second processing means is configured to join the user terminal to the multicast multicast member and deliver the multicast data stream to the user terminal when the multicast data requested by the user terminal has been provided to the user terminal.

The control device according to any one of claims 10 to 13, further comprising:

a fourth receiving device, configured to receive an exit multicast group request message from the user terminal, where the exit multicast group request message is used to request to exit a multicast group;

a third determining device, configured to determine, according to the exiting the multicast group request message, whether the base station further provides the multicast data corresponding to the multicast group to a user other than the user that sends the exiting multicast group request message Flow

a third processing device, configured to: when the base station further provides the multicast data stream corresponding to the multicast group for the user terminal other than the user terminal that sends the exiting multicast group request message, The multicast data forwarding table is deleted from the outgoing exit group Information about the user terminal that broadcasts the request message; and

a fourth processing device, configured to: when the base station only provides the multicast data stream corresponding to the multicast group by the user terminal that sends the multicast group request message, the multicast data forwarding table maintained by the base station And deleting the related information of the user terminal that sends the exiting multicast group request message, and sending the exiting multicast group request message to the upper-level network device according to the multicast management protocol.

The control device according to claim 14, wherein the fourth processing device comprises:

a second updating device, configured to replace source address information in the exit multicast request message with address information of the base station, to obtain a new exit multicast group request message; and a sixth sending device, configured to use the group The broadcast management protocol sends the new exit multicast group request message to the upper-level network device.

The control device according to any one of claims 11 to 15, wherein the network device comprises any one of the following: a router, a switch, and a gateway device.

The control device according to any one of claims 11 to 16, wherein the multicast management protocol comprises an IPv4 multicast management protocol, the multicast join request message, and/or an exit multicast group request. The message includes an IGMP message.

The control device according to any one of claims 11 to 16, wherein the multicast management protocol comprises an IPv6 multicast management protocol, the multicast join request message and/or an exit multicast group request. Message MLD message.

A base station device in a WiMAX system for controlling transmission of a data packet in an access service network, characterized by comprising a control device according to any one of claims 10 to 18.

20. A control method for controlling transmission of a multicast data packet in an access service network in an access service network gateway device of a WiMAX system, comprising the steps of:

The multicast data packet to be transmitted is sent to the network link connected to the outbound interface by using the outbound interface corresponding to the multicast data packet according to the multicast address of the multicast data packet to be transmitted and the multicast data forwarding table information. The tunnel, where the multicast data packet to be transmitted is not tunnel encapsulated.

The method according to claim 20, further comprising the following steps before the step c:

a. receiving a data packet to be transmitted;

c determining whether the data packet to be transmitted is a multicast data packet;

The step c includes:

And if the data packet to be transmitted is a multicast data packet, the multicast data packet to be transmitted is passed through the multicast data according to the multicast address and the multicast data forwarding table of the multicast data packet to be transmitted. The outbound interface corresponding to the packet is sent to the network link connected to the outbound interface, where the multicast data packet to be transmitted is not tunnel encapsulated.

22. The method according to claim 21, further comprising the following steps:

d. If the data packet to be transmitted is a unicast data packet, the unicast data packet to be transmitted is tunnel encapsulated and transmitted to the corresponding destination base station.

The method according to any one of claims 20 to 22, wherein the step c further comprises the following steps:

Determining an outbound interface corresponding to the multicast data packet according to the multicast address of the multicast data packet to be transmitted and the multicast data forwarding table information;

- transmitting the multicast data packet to be transmitted to the network link through the outbound interface.

The method according to any one of claims 20 to 23, further comprising the steps of:

- receiving a multicast join request message and/or a multicast exit request message;

- establishing or updating the multicast data forwarding table according to the multicast join request message and/or the multicast exit request message.

The method of any one of claims 20 to 24, wherein the tunnel comprises a generic routing encapsulation tunnel.

26. A control device for controlling multicast data packet transmission in an access service network gateway device of a WiMAX system, comprising:

a first sending device, configured to: according to a multicast address and a multicast number of the multicast packet to be transmitted Transmitting the multicast data packet to be transmitted to the network link connected to the outbound interface by using the outbound interface corresponding to the multicast data packet, where the multicast data packet to be transmitted is not performed. Tunnel encapsulation.

The control device according to claim 26, further comprising: a first receiving device, configured to receive a data packet to be transmitted;

a first determining device, configured to determine whether the data packet to be transmitted is a multicast data packet, where the first sending device is further configured to: when the data packet to be transmitted is a multicast data packet, according to the to-be-transmitted And a multicast data forwarding table of the multicast data packet, where the multicast data packet to be transmitted is sent to the network link connected to the outbound interface by using an outbound interface corresponding to the multicast data packet, where The multicast data packet to be transmitted is not tunnel encapsulated.

The control device according to claim 27, further comprising: a second sending device, configured to: when the data packet to be transmitted is a unicast data packet, perform the data packet to be transmitted The tunnel is encapsulated and transmitted to the corresponding destination device.

The control device according to any one of claims 26 to 28, wherein the first transmitting device further comprises:

Determining means, configured to determine an outbound interface corresponding to the multicast data packet according to the multicast address of the multicast data packet to be transmitted and the multicast data forwarding table information;

And a third sending device, configured to send the multicast data packet to be transmitted to the network link by using the outbound interface.

The control device according to any one of claims 26 to 29, further comprising:

a second receiving device, configured to receive a multicast join request message and/or a multicast exit request message;

The routing maintenance device is configured to establish or update the multicast data forwarding table information according to the multicast join request message and/or the multicast exit request message.

The control device according to any one of claims 26 to 30, wherein the tunnel comprises a general routing encapsulation tunnel.

An access service network gateway device for use in a WiMAX system, characterized by comprising the control device according to any one of claims 26 to 31.