WO2013007133A1

WO2013007133A1 - Method and system for managing packet forwarding path, and network element

Info

Publication number: WO2013007133A1
Application number: PCT/CN2012/075722
Authority: WO
Inventors: 刘娟; 骆文; 孙默
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-07-08
Filing date: 2012-05-18
Publication date: 2013-01-17
Also published as: CN102868991B; CN102868991A

Abstract

A method for managing a packet forwarding path comprises: a first mobile access gateway (MAG) sending an address query request to a mapping server, the address query request carrying node information of a correspondent node (CN); the mapping server receiving the address query request, querying a binding caching table, obtaining MAG information of the CN corresponding to the node information of the CN, the MAG information of the CN pointing to a second MAG; the mapping server directly sending an address query response message to the first MAG, or after forwarding the address query request to the second MAG, the second MAG sending the address query response message to the first MAG, the query response message carrying the MAG information of the CN; and the first MAG receiving the address query response message.

Description

Message forwarding path management method, system and network element

Technical field

The present invention relates to the field of mobile communications, and in particular, to a packet forwarding path management method, system, and network element (including a mobile access gateway (MAG) and a mapping server). Background technique

The ΡΜΙΡνό protocol is a network-based mobility management protocol. The mobile node (MN) does not need to participate in any IP mobile-related signaling procedure. The mobile entity in the network tracks the mobile node's mobility and initiates the mobile signaling process. Set the required routing status. The core functional entities in the PMIPv6 domain are the Local Mobility Anchor (LMA) and the Mobile Access Gateway (MAG). The local mobility anchor is responsible for maintaining the reachability status of the mobile node and logically anchoring the mobile node's home network prefix. On the LMA, the LMA accepts any packet sent to the mobile node by any node within the proxy mobile IPv6 domain or outside the domain. The mobile access gateway is responsible for managing the mobility related signaling of the MN, tracking the movement of the mobile node in the access network, receiving any packets sent by the mobile node to the correspondent node and transmitting to the local mobility anchor via the bidirectional tunnel.

As shown in Figure 1, the data transmission path between the MN and the CN (Correspondent Node) in PMIPv6 is attached to the MAG1, and the CN is attached to the MAG2. The packet sent by the MN to the CN first arrives at the MAGI. The MAG1 tunnels the packet and sends the packet to the LMA through the tunnel between the MAG1 and the LMA. The LMA decapsulates the packet and repackages the packet through the LMA and The tunnel between MAG2 is sent to MAG2. After decapsulation, MAG2 forwards it to the CN. The CN sends the message to the MN in the same way.

上述 Using the above method, the data between the MN and the CN always needs to be forwarded through the fixed anchor point LMA, the data transmission path is not the optimal path, and the LMA decapsulation and secondary re-encapsulation processing are required in the message transmission process. Causes large data transmission delays and packet loss. Especially when the network tends to be flat and the amount of data is large, LMA becomes the bottleneck of traffic forwarding, which is easy to cause single point of failure and affects the scalability of LMA. Summary of the invention

The technical problem to be solved by the present invention is to provide a packet forwarding path management method, a network element, and a system to solve the problem that the LAM becomes a bottleneck of traffic forwarding.

To solve the above technical problem, the present invention provides a packet forwarding path management method, where the method includes:

The first mobile access gateway (MAG) sends an address query request to the mapping server, where the node information of the peer node (CN) is carried;

The mapping server receives the address query request, queries the binding cache table, and acquires the mobile access gateway information of the CN corresponding to the node information of the CN, where the mobile access gateway information of the CN points to the second MAG;

After the mapping server sends an address query response message to the first MAG, or after forwarding the address query request to the second MAG, the second MAG sends an address query response message to the first MAG, where the query The response message carries the mobile access gateway information of the CN; the first MAG receives the address query response message.

Preferably, before the first MAG sends the address query request, the method further includes: the first MAG receiving and buffering the first message sent by a mobile node (MN); a first transmission tunnel of the second MAG, and forwarding the first packet by using the first transmission tunnel.

Preferably, before the first MAG sends the address query request, the method further includes: receiving, by the first MAG, a first packet sent by a mobile node (MN), where a destination address of the first packet is the CN The home address; the address query request further includes the first message; after the mapping server queries the mobile access gateway information of the CN, directly forwards the first text to the second MAG or passes the The address query message forwards the first message to the second MAG.

Preferably, the address query request further carries the node information of the MN and the mobile access gateway information; after receiving the address query request message, the second MAG establishes a location according to the mobile access gateway information of the MN. a second transmission tunnel of the first MAG, and storing a mapping relationship between the node information of the MN and the mobile access gateway information.

Preferably, after the first MAG receives the address query response message, the method further includes: The first MAG saves a mapping relationship between the node information of the CN and the mobile access gateway information; the first MAG forwards the received first packet to the outer tunnel address according to the mapping relationship, and the CN Mobile access gateway information.

Preferably, after receiving the encapsulated first message, the second MAG establishes a second transmission tunnel to the first MAG according to the mobile access gateway information of the MN, and saves the node information of the MN. Mapping relationship with mobile access gateway information.

Preferably, the binding cache table includes a plurality of binding cache entries, where the binding cache entry is generated when the corresponding MN is registered, and the process of registering the MN includes:

Sending, by the MN, a router request message to the attached MAG, requesting to obtain a home network prefix; after receiving the router request message, the MAG sends a proxy binding update message to the mapping server;

After receiving the proxy binding update message, the mapping server allocates a home network prefix to the MN, and creates a binding cache entry to save the saved binding relationship to the MN's home network prefix and proxy care-of address. Binding relationship

The mapping server replies to the MAG with a proxy binding acknowledgement message, where the message carries a home network prefix assigned to the MN;

After receiving the proxy binding acknowledgement message, the mobile access gateway sends a router advertisement message to the MN, where the message includes a home network prefix allocated by the mapping server to the MN and related parameters used by the MN to perform address configuration.

After receiving the router advertisement message, the MN configures to generate a home address.

To solve the above technical problem, the present invention further provides a mobile access gateway (MAG), which is a mobile node MAG corresponding to a mobile node (MN), and the MAG includes:

The query request sending module is configured to: send an address query request to the mapping server, and carry node information of the peer node (CN);

The query response receiving module is configured to: receive an address query response message, and carry the mobile access gateway information of the CN.

Preferably, the MAG further includes: a transmission tunnel establishing module, configured to: when the mobile node MAG is configured, establish a first transmission tunnel to the opposite node MAG corresponding to the CN according to the mobile access gateway information of the CN in the address query response message;

The message buffering module is configured to: when the mobile node is a MAG, cache the first message received before the first transmission tunnel is established;

The packet forwarding module is configured to: when the mobile node is a MAG, perform the first packet forwarding after the first transmission tunnel is established.

Preferably, the address query request further carries the node information of the mobile node (MN) and the mobile access gateway information; as the peer node MAG corresponding to the CN, the MAG further includes:

The query request receiving module is configured to: receive an address query request sent by the mapping server; the query response sending module is configured to: according to the MN, the mobile access gateway information in the address query request to the mobile node MAG corresponding to the MN Send an address query response message.

Preferably, the address query response message is sent by the mapping server or the peer node MAG.

Preferably, the MAG further includes a mapping relationship maintenance module, as the mobile node MAG: the mapping relationship maintenance module is configured to: save the mapping of the CN node information and the mobile access gateway information according to the address query response message Relationship

The packet forwarding module is further configured to: encapsulate the outer tunnel address of the first packet before forwarding, the outer source address of the encapsulation is the mobile access gateway information of the MN, and the destination address is the movement of the CN Access gateway information.

Preferably, when the peer node is a MAG:

The transmission tunnel establishing module is further configured to: establish a second transmission tunnel to the mobile node MAG corresponding to the MN according to the mobile access gateway information of the MN in the address query request.

Preferably, when the peer node is a MAG: the mapping relationship maintenance module is further configured to: save a mapping relationship between the node information of the MN and the mobile access gateway information according to the address query request.

To solve the above technical problem, the present invention also provides a mapping server, the mapping service The device includes:

The query request receiving module is configured to: receive an address query request sent by the mobile node MAG corresponding to the mobile node, where the node information of the peer node (CN) is carried;

a binding relationship maintenance module, configured to: save a binding relationship, and include a binding relationship between the node of the CN and the mobile access gateway information;

a binding relationship query module, configured to: query the saved binding relationship, and obtain information about the mobile access gateway of the CN corresponding to the home node of the peer node;

a query request processing module, configured to: send an address query response message to the mobile node MAG, carrying the mobile access gateway information of the CN; or, according to the mobile access gateway information of the CN, to the CN The peer node MAG forwards the address query request.

Preferably, the address query request further carries a first message, and the destination address of the first message is node information of the CN.

Preferably, the mapping server further includes a packet forwarding module, configured to: forward the first packet to the peer node MAG according to the mobile access gateway information of the CN.

Preferably, the mapping server further includes:

a proxy binding update message receiving module, configured to: receive a proxy binding update message sent by a mobile node (MN) mobile access gateway (MAG);

The home network prefix allocation module is configured to: assign a home network prefix to the MN; a proxy binding confirmation message sending module, configured to: reply a proxy binding confirmation message to the mobile node MAG, where the message carries the hometown assigned to the MN Network prefix

The binding relationship saved by the binding relationship maintenance module is a binding relationship between the home network prefix and the proxy care-of address of the MN saved according to the allocated home network prefix and the proxy binding update message.

To solve the above technical problem, the present invention also provides a message forwarding path management system including the mobile access gateway (MAG) as described above.

Preferably, the system further comprises the above mapping server.

A packet forwarding path management method, a network element, and a system are attached by a mobile node (MN) according to an embodiment of the present invention. The mobile access gateway (MAG) queries the mobile access gateway information of the correspondent node (CN) to implement packet forwarding between the MN and the CN through the two mobile access gateways, thereby solving the traffic forwarding bottleneck caused by the LMA. problem. BRIEF abstract

Figure 1 is a proxy mobile IPv6 packet forwarding path diagram;

2 is a structural diagram of a packet forwarding system according to an embodiment of the present invention;

FIG. 3 is a flowchart of a mobile node registration according to Embodiment 1 of the present invention;

4 is a flowchart of a packet forwarding method according to Embodiment 2 of the present invention;

FIG. 5 is a flowchart of a packet forwarding method according to Embodiment 3 of the present invention;

6 is a flowchart of a packet forwarding method according to Embodiment 4 of the present invention;

7 is a flowchart of a packet forwarding method provided in Embodiment 5 of the present invention;

8 is a schematic diagram of a packet forwarding path management method according to the present invention;

9 to FIG. 11 are schematic diagrams showing the structure of a module of a mobile access gateway according to the present invention; and FIG. 12 is a schematic structural diagram of a module of an embodiment of a mapping server according to the present invention. Preferred embodiment of the invention

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

The embodiment of the present invention is applied to a scenario in which a mobile node (MN) and a correspondent node (CN) are attached to different mobile access gateways, and the proxy mobile IPv6 protocol provides a route when the MN and the CN are attached to the same mobile access gateway. Optimization mechanism.

FIG. 2 is a structural diagram of a packet forwarding system according to an embodiment of the present invention, where:

200, the mapping server in the present invention is a control plane entity, receives a proxy binding update message from the mobile access gateway, and saves a mapping relationship between the mobile node home network prefix and the proxy care-of address; assigns a home network prefix to the mobile node; Receiving an address query request message from the mobile access gateway, performing corresponding processing according to whether the first message is carried in the message; and sending an address query response message to the mobile access gateway sending the address query request message. 201. The first mobile access gateway receives the first packet sent by the mobile node to the opposite node, sends an address query message to the mapping server, and queries the proxy care-of address of the opposite node. The mobile access gateway optimizes the data forwarding path between the MN and the CN according to the obtained proxy care-of address of the opposite node.

The address query message is constructed in two cases:

Carrying the first packet, the first mobile access gateway does not need to store the first packet, and after the mapping server receives the address query message carrying the first packet, the mapping packet is forwarded in the next step;

The first mobile access gateway needs to store the first packet, and the first packet is encapsulated and sent to the second mobile access gateway by using the care-of address queried by the mapping server.

The present invention implements mobility management by introducing a mapping server and using a plane structure in which the control plane is separated from the bearer plane. The control plane mapping server is responsible for the registration and location management of the mobile node, which is equivalent to a location database. The bearer plane mobile access gateway transmits the data packets between the mobile node and the communication node by performing location query on the mapping server. Provide a mobility management mechanism with efficient data transfer efficiency, adequate network utilization, good scalability, and robustness.

It should be noted that the node information in the present invention is information for indicating which mobile node or the opposite node is, and may be an identifier (ID) of the mobile node or the opposite node, a home address, or a home network prefix. And the combination of the two pieces of information or the three pieces of information; the mobile access gateway information of the present invention is used to indicate which MAG is the information of the MAG attached to the mobile node or the peer node, and may be the MAG. The address may also be a proxy care-of address (CoA) allocated by the MAG for the mobile node (MN) and the correspondent node (CN), or may be a combination of the address of the MAG and the CoA. The node information is specifically represented by what information, and the information of the mobile access gateway information is specifically determined by the specific application scenario or the information that may be obtained by the corresponding network element. This is not the focus of the present invention, and the present invention does not limit this. The detailed description of the embodiments is merely illustrative and should not be construed as limiting.

The packet forwarding path management method of the present invention is as shown in FIG. 8. The method includes:

Step 801: The first mobile access gateway (MAG) sends an address query request to the mapping server, where the node information of the opposite node (CN) is carried;

As described above, the node information is an identifier (ID), a home address, and/or a home network prefix. Which one or the other information is carried as the node information, so that the specific binding relationship saved in the mapping server can be found according to the node information in the query request;

Step 802: The mapping server receives the address query request, queries the binding cache table, and obtains the mobile access gateway information of the CN, where the mobile access gateway information of the CN points to the second MAG;

Step 803: After the mapping server sends an address query response message to the first MAG, or after forwarding the address query request to the second MAG, the second MAG sends an address query response message to the first MAG. The query response message carries the mobile access gateway information of the CN;

The mobile access gateway information of the CN is an address of the second MAG or the second MAG is the

CN assigned proxy care-of address;

Step 804: The first MAG receives the address query response message.

The above steps 801 to 804 mainly focus on how the first MAG obtains the proxy handover address of the opposite node.

Optionally, before the sending, by the first MAG, the address query request, the method further includes: the first MAG receiving and buffering the first packet sent by a mobile node (MN); a first transmission tunnel of the second MAG, and performing the first packet forwarding by using the first transmission tunnel. See Example 2 and Example 3 for details.

Optionally, before the first MAG sends the address query request, the method further includes: receiving, by the first MAG, a first packet sent by a mobile node (MN), where a destination address of the first packet is The home address of the CN; the address query request further carries the first message; after the mapping server queries the proxy care-of address of the CN, directly forwards the first message to the second MAG or passes the The address query message forwards the first message to the second MAG. See Example 4 and Example 5 for details.

Optionally, the address query request further carries the node information of the MN and the mobile access gateway information, where the mobile access gateway information is an address of the first MAG, or the first MAG is allocated to the MN. After the second MAG receives the address query request message, the second MAG establishes a second transmission tunnel to the first MAG according to the mobile access gateway information of the MN, and

8 The mapping relationship between the node information of the MN and the mobile access gateway information is saved. See the embodiment for details.

3 and Example 5.

After the first MAG receives the address query response message, the method further includes: the first MAG saves a mapping relationship between the node information of the CN and the mobile access gateway information; The mapping relationship encapsulates the received first packet with the outer tunnel address and the address is the mobile access gateway information of the CN. See Embodiments 2 and 3 for details.

Optionally, after receiving the encapsulated first packet, the second MAG establishes a second transmission tunnel to the first MAG according to the mobile access gateway information of the MN, and saves the node of the MN. The mapping relationship between information and mobile access gateway information. See Example 2 and Example 4 for details.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

Example 1

In the present invention, the binding cache table in the mapping server includes a plurality of binding cache entries, and the binding cache entries are generated when the corresponding MN is registered. As shown in FIG. 3, it is a mobile node registration process provided by Embodiment 1 of the present invention. Includes the following steps:

Step 300: When the MN is attached to the mobile access gateway, the mobile access gateway acquires the MN-ID, obtains the configuration file of the MN from the AAA server, performs an authentication operation on the MN according to the configuration file, and determines whether the mobile device can provide the mobile device with the MN. Sex management services.

Step 301: The MN sends a router request message to the attached mobile access gateway, requesting to obtain the prefix of the current visited network (ie, the home network prefix), to configure the IP address of the MN (ie, the home address), and the request message carries the identifier of the MN. (ID).

It can be understood that the steps 301 and 302 have no strict sequence, and the router request message can be sent at any time after the MN is attached.

Step 302: After the mobile access gateway authenticates the MN, construct a proxy binding update message.

(PBU, Proxy Binding Update) is sent to the mapping server, and the MN is registered on the mapping server. The proxy binding update message carries the identifier (ID) of the MN, the address of the mobile access gateway, and the mobile access gateway allocates the MN. Proxy Care-of Address (CoA). Step 303: After receiving the proxy binding update message, the mapping server allocates a home network prefix to the MN, and creates a binding cache entry (BCE: Binding Cache Entry, BCE) to save the binding of the MN home network prefix and the proxy care-of address. relationship.

Step 304: The mapping server replies to the mobile access gateway with a proxy binding acknowledgement message, where the message carries the home network prefix assigned to the MN.

Step 305: After receiving the proxy binding acknowledgement message, the mobile access gateway creates a Binding Update List (BUL) for the MN to record information about the binding update message sent by the MN. And sending a router advertisement message to the MN, where the message includes a home network prefix assigned by the mapping server to the mobile node and related parameters used by the MN for address configuration.

Step 306: After receiving the router advertisement message, the mobile node configures its interface address according to the configuration mode indicated in the message, that is, the stateful or stateless address configuration mode. After the address configuration succeeds, the MN obtains the hometown originating from the home network prefix. address.

The above embodiment of the present invention registers the mobile node on the mapping server by the mobile access gateway, and the mapping server allocates the home network prefix to the mobile node, and the mobile node configures the home address accordingly. The mapping server stores location information of all mobile nodes in the administrative domain, so that different mobile nodes can perform location query when communicating with each other.

In the above embodiment, the mapping server stores the binding relationship between the home network prefix and the proxy care-of address. The purpose of the MN registration is to store the binding relationship between the node information of the MN and the mobile access gateway information in the mapping server. Alternatively, in addition to the home network prefix, the mapping server may also use the identifier (ID) of the MN carrying the PBU message as the node information in the binding relationship, or the MN may feed back the configured home address to the mapping server. The node information in the relationship is determined. In addition to the proxy care-of address, the mapping server can also use the address of the mobile access gateway carried in the PBU message as the mobile access gateway information in the binding relationship.

The embodiment of the present invention provides a method for packet forwarding to optimize the data forwarding path between the MN and the CN. After the first packet is forwarded, the subsequent data packet is directly forwarded through the tunnel between the MAGs.

Example 2

In this embodiment, the first mobile access gateway (ie, the MAG attached to the mobile node, the present invention)

10 The mobile node (MAG) also stores the first message sent by the mobile node to the opposite node; and obtains the proxy care-of address of the opposite node by sending an address query message to the mapping server (the proxy care-of address points to the MAG attached to the peer node, The MAG also becomes the peer node MAG), and the query message carries the node information of the opposite node; the transmission tunnel of the first mobile access gateway to the second mobile access gateway is established according to the query result; the first stored by the established tunnel The packet is sent to the second mobile access gateway, and finally forwarded to the opposite node. Subsequent messages are forwarded directly through the tunnel between the mobile access gateways.

Specifically, as shown in FIG. 4, a flow chart of a packet forwarding method according to Embodiment 2 of the present invention includes the following steps:

Step 400: The mobile node MN sends the first message to the opposite node CN.

The destination address of the first message is CN's home address (HoA), and the source address is the home address of the MN.

Step 401: After receiving the first packet, the first mobile access gateway uses the node information of the CN as an index to query the mapping routing table to obtain the mobile access gateway information of the CN (which may be a proxy care-of address (Proxy-CoA), or may be The address of the mobile access gateway is shown in the figure as Proxy-CoA. The following example is used. If the call is missed, the first packet is cached.

Specifically, the first mobile access gateway uses the HoA as the index or the HNP as the index to be queried, which is determined according to the specific content of the mapping of the mapping routing table, which is not limited by the present invention.

Step 402: The first mobile access gateway sends an address query request message to the mapping server to query the proxy care-of address of the CN, where the query request message carries the CN node information, which may be a home address (HoA) or a home network prefix (HNP). In the figure, HNP is taken as an example, and the following embodiments are the same.

Step 403: After receiving the address query request message, the mapping server queries the BCE to obtain the proxy care-of address of the CN by using the home network prefix of the CN as an index, and the mapping server sends an address query response message to the first mobile access gateway, where the message carries the CN. Agent transfer address.

Step 404, creating a mapping routing table. After receiving the address query response message of the mapping server, the first mobile access gateway extracts the proxy care-of address of the CN, establishes a mapping routing table locally, and saves the mapping relationship between the CN node information and the mobile access gateway information, and the mapping relationship may also be It is saved in the original binding update list of the first mobile access gateway.

11 In step 405, a tunnel is established. The first mobile access gateway establishes a unidirectional tunnel to the second mobile access gateway according to the proxy care-of address of the CN (also becomes the first transport tunnel in the present invention). In step 406, the first message is sent. The first mobile access gateway tunnel encapsulates the first packet stored in step 401 according to the established mapping routing table: the source address of the outer IP header is the mobile access gateway information of the MN (for example, the proxy care-of address, or the first The address of a mobile access gateway, the destination address is the mobile access gateway information of the CN (such as the proxy care-of address or the address of the second MAG); the source address of the inner-layer IP header is the node information of the MN, and the destination address is the CN Node information. The first mobile access gateway sends the encapsulated first message to the second mobile access gateway.

Step 407: The second mobile access gateway receives the first message sent by the first mobile access gateway through the tunnel, learns the node information of the MN and the mobile access gateway information, establishes a mapping routing table locally, and saves the node information and the mobile of the MN. The mapping relationship between the access gateway information and the mapping relationship may also be saved in the original binding update list of the second mobile access gateway.

Step 408: The second mobile access gateway strips the outer tunnel header of the packet, and forwards the first packet to the second packet.

CN.

Step 409: The second mobile access gateway establishes a unidirectional tunnel to the first mobile access gateway according to the learned proxy care-of address of the MN (in combination with the unidirectional tunnel established in step 405 (the invention also becomes the first transmission). Tunnel), the two-way tunnel between the first mobile access gateway and the second mobile access gateway is successfully established).

Step 410 to step 412, subsequent packet forwarding. In the above step, the mapping routing table established by the first mobile access gateway stores the mapping relationship between the node information of the CN and the mobile access gateway information; the mapping routing table established by the second mobile access gateway stores the node of the MN. Mapping relationship between information and mobile access gateway information; a two-way tunnel is established between the first mobile access gateway and the second mobile access gateway. The subsequent data packets between the MN and the CN are forwarded through the bidirectional tunnel between the mobile access gateways. After the data packets arrive at the respective mobile access gateways, the local mapping routing table is first searched according to the destination address of the packet, and then The packet is encapsulated according to the information of the mobile access gateway corresponding to the destination address, and the encapsulated packet is sent to the mobile access gateway of the other party through the tunnel. Finally, the mobile access gateway decapsulates the packet. Forward to the peer node.

In the above embodiment, the mobile access gateway stores the first packet, obtains the mobile access gateway information of the peer node from the mapping server, encapsulates the first packet, and sends the packet to the peer mobile access gateway.

12 It avoids the packet transmission delay caused by the need to traverse fixed anchor points in PMIPv6, shortens the forwarding path, and improves communication efficiency. The mobile access gateway optimizes the forwarding path of subsequent data packets between the MN and the CN by creating a mapping routing table. Example 3

In this embodiment, the first mobile access gateway stores the first message sent by the mobile node to the opposite node; the proxy forwarding address of the opposite node is obtained by sending an address query message to the mapping server, and the query message carries the peer node. Node information, and node information of the MN, mobile access gateway information of the MN; establishing a transmission tunnel of the first mobile access gateway to the second mobile access gateway according to the query result; sending the first packet stored by establishing a good tunnel The second mobile access gateway is forwarded to the opposite node. Subsequent messages are forwarded directly through the tunnel between the mobile access gateways.

As shown in FIG. 5, it is a flowchart of a packet forwarding method according to Embodiment 3 of the present invention. Includes the following steps:

Step 500: The mobile node MN sends the first packet to the opposite node CN.

The destination address of the first message is the home address of CN, and the source address is the home address of the MN.

Step 501: After receiving the first packet, the first mobile access gateway uses the home information of the CN as an index to query the mapping routing table to obtain the proxy care-of address of the CN. If not, the first mobile access gateway stores the first packet.

Step 502: The first mobile access gateway sends an address query request message to the mapping server to query the proxy care-of address of the CN, and the query request message carries the node information of the CN, the node information of the MN, and the mobile access gateway information.

Step 503: After receiving the address query request message, the mapping server queries the BCE to obtain the proxy care-of address of the CN by using the home network prefix of the CN as an index, and forwards the message to the second mobile access gateway.

Step 504: After receiving the address query request message, the second mobile access gateway extracts the node information of the MN and the mobile access gateway information in the message, and establishes a mapping routing table, and saves the mapping between the node information of the MN and the information of the mobile access gateway. Relationship, the mapping relationship may also be saved in the original binding update list of the second mobile access gateway.

Step 505, establishing a tunnel. Establish a one-way tunnel to the first mobile access gateway,

13 Step 506: The second mobile access gateway returns an address query response message to the first mobile access gateway, where the message carries the proxy care-of address of the CN.

Step 507, creating a mapping routing table. After receiving the address query response message of the second mobile access gateway, the first mobile access gateway extracts the mobile access gateway information of the CN, establishes a mapping routing table locally, and saves the mapping relationship between the CN node information and the mobile access gateway information. The mapping relationship may also be saved in the original binding update list of the first mobile access gateway.

Step 508, establishing a tunnel. The first mobile access gateway establishes a unidirectional tunnel to the second mobile access gateway according to the mobile access gateway information of the CN (in combination with the unidirectional tunnel established in step 505, the first mobile access gateway and the second mobile access The two-way tunnel between the gateways was successfully established).

Step 509: The first mobile access gateway tunnels the first packet stored in step 501 according to the established mapping routing table: the source address of the outer IP header is the mobile access gateway information of the MN, and the destination address is CN. Mobile access gateway information; the source address of the inner layer IP header is the home address of the MN, and the destination address is the home address of the CN. The first mobile access gateway sends the encapsulated first message to the second mobile access gateway.

Step 510: After receiving the first packet sent by the first mobile access gateway through the tunnel, the second mobile access gateway strips the outer tunnel header of the data packet and forwards the first packet to the CN.

Steps 511 to 513 are the same as steps 410 to 412, and will not be described again.

The foregoing embodiment of the present invention uses the mobile access gateway to store the first packet, obtains the mobile access gateway information of the peer node from the peer mobile access gateway, encapsulates the first packet, and sends the packet to the peer mobile access gateway to avoid In PMIPv6, the packet transmission delay caused by the fixed anchor point needs to be shortened, the forwarding path is shortened, and the communication efficiency is improved. The mobile access gateway optimizes the forwarding path of subsequent data packets between the MN and the CN by creating a mapping routing table.

Example 4

In this embodiment, the first mobile access gateway receives the first message sent by the mobile node to the opposite node; and obtains the proxy care-of address of the opposite node by sending an address query message to the mapping server, where the query message carries the peer node The home information, and the first message; the mapping server extracts the first message from the query message, sends it to the second mobile access gateway, and finally forwards it to the peer node. Subsequent messages are forwarded directly through the tunnel between the mobile access gateways.

14 As shown in FIG. 6, the flow chart of the packet forwarding method provided by Embodiment 4 of the present invention includes the following steps: Step 600: The mobile node MN sends the first message to the opposite node CN.

Step 601: After receiving the first packet, the first mobile access gateway uses the home information of the CN as an index to query the mapping routing table to obtain the proxy care-of address of the CN, and the first mobile access gateway sends an address query request message to the mapping server. The message carries the first message and CN's hometown information.

Step 602: After receiving the address query request message, the mapping server queries the BCE to obtain the proxy care-of address of the CN, and extracts the first packet in the message to be forwarded to the second mobile access gateway.

Step 603: The second mobile access gateway receives the first packet forwarded from the mapping server, and forwards the packet to the CN.

Step 604: The mapping server performs the step 602, and sends an address query response message to the first mobile access gateway, where the message carries the proxy care-of address of the CN.

Step 605: Create a mapping routing table and establish a tunnel. After receiving the address query response message of the mapping server, the first mobile access gateway extracts the proxy care-of address of the CN, establishes a mapping routing table locally, and saves the mapping relationship between the CN node information and the mobile access gateway information, and the mapping relationship may also be The first mobile access gateway establishes a one-way tunnel to the second mobile access gateway according to the proxy care-of address of the CN.

Step 606 to step 608, after the tunnel of the first mobile access gateway to the second mobile access gateway is established, the subsequent data packets sent by the MN to the CN are forwarded through the tunnel. After receiving the data packet forwarded by the first mobile access gateway through the tunnel, the second mobile access gateway learns the node information of the MN and the mobile access gateway information, establishes a mapping routing table, and saves the node information of the MN and the mobile access gateway. The mapping relationship of information.

Step 609: The second mobile access gateway establishes a unidirectional tunnel to the first mobile access gateway according to the learned proxy care-of address of the MN (in combination with the unidirectional tunnel established in step 605, the first mobile access gateway and the first The two-way tunnel between the mobile access gateways is successfully established.

Steps 610 to 612 are the same as steps 410 to 412, and are not described again.

The foregoing embodiment of the present invention carries the first message by mapping the server in the address query request message.

15 Extracting the first packet from the message for forwarding, and responding to the address query response message by the mobile access gateway that sends the address query request message to establish a tunnel between the mobile access gateways, and the subsequent data packets of the MN and the CN are forwarded through the tunnel. It avoids the packet transmission delay caused by the need to traverse fixed anchor points in PMIPv6, shortens the forwarding path, and improves communication efficiency.

Example 5

In the embodiment 5, the first mobile access gateway receives the first packet sent by the mobile node to the opposite node, and obtains the care-of address of the opposite node by sending an address query message to the mapping server, where the query message carries the node of the opposite node. The information, the node information of the MN, and the mobile access gateway information, the first message; the mapping server forwards the query message to the second mobile access gateway; and the second mobile access gateway extracts the first message and sends the first message to the opposite node. Subsequent messages are forwarded directly through the tunnel between the mobile access gateways.

FIG. 7 is a flowchart of a packet forwarding method according to Embodiment 5 of the present invention. Includes the following steps:

Step 700: The mobile node MN sends the first packet to the opposite node CN.

Step 701: After receiving the first message, the first mobile access gateway uses the home information of the CN as an index to query the mapping routing table to obtain the proxy care-of address of the CN, and the first mobile access gateway sends an address query request message to the mapping server. The message carries the first message, CN's home network information, MN node information, and mobile access gateway information.

Step 702: After receiving the address query request message, the mapping server queries the BCE to obtain the proxy care-of address of the CN by using the home network prefix of the CN as an index, and forwards the message to the second mobile access gateway.

Step 703: Forward the first packet, and create a mapping routing table. After receiving the address query request message, the second mobile access gateway extracts the first message in the message and forwards it to the CN.

Extracting the node information of the MN and the mobile access gateway information address in the message, establishing a mapping routing table locally, and preserving the mapping relationship between the node information of the MN and the mobile access gateway information, and the mapping relationship may also be saved in the second mobile access gateway. The original bindings are updated in the list.

Step 704, establishing a tunnel. The second mobile access gateway according to the mobile access gateway information of the MN,

16 Establish a one-way tunnel to the first mobile access gateway.

Step 705: The second mobile access gateway sends an address query response message to the first mobile access gateway, where the message carries the mobile access gateway information of the CN.

Step 706: Create a mapping routing table and establish a tunnel. After receiving the address query response message of the second mobile access gateway, the first mobile access gateway extracts the mobile access gateway information of the CN, establishes a mapping routing table locally, and saves the mapping relationship between the CN node information and the mobile access gateway information. The mapping relationship may also be saved in the original binding update list of the first mobile access gateway; the first mobile access gateway establishes a one-way tunnel to the second mobile access gateway according to the proxy care-of address of the CN (in combination step The unidirectional tunnel established in 704, the bidirectional tunnel between the first mobile access gateway and the second mobile access gateway is successfully established).

Steps 707 to 709 are the same as steps 410 to 412, and are not described again.

In the foregoing embodiment of the present invention, the mobile access gateway extracts the first packet from the message by using the first packet in the address query request message, and forwards the response message to the mobile access gateway that sends the address query request message to establish an address query response message. In the tunnel between the mobile access gateways, the subsequent data packets of the MN and the CN are forwarded through the tunnel, which avoids the packet transmission delay caused by the need to traverse the fixed anchor point in the PMIPv6, shortens the forwarding path, and improves the communication efficiency.

Corresponding to the foregoing method embodiments, the functional modules of the mobile access gateway (MAG) of the present invention that are particularly relevant to the present invention are described below.

As shown in FIG. 9, when the MAG is the mobile node MAG corresponding to the mobile node (MN), that is, the first MAG, the MAG includes:

The query request sending module is configured to send an address query request to the mapping server, where the node information of the peer node (CN) is carried, where the node information is a CN identifier, a home address, or a home network prefix;

a query response receiving module, configured to receive an address query response message, where the mobile access gateway information of the CN is carried, where the mobile access gateway information is an address of a peer node MAG or a proxy that the peer node allocates for the CN Handover address.

Optionally, corresponding to the embodiment 2, 3, as shown in FIG. 10, on the basis of the MAG shown in FIG. 9, the MAG further includes:

17 a transmission tunnel establishing module, as the mobile node MAG, configured to establish a first transmission tunnel to the opposite node MAG corresponding to the CN according to the mobile access gateway information of the CN in the address query response message;

The message buffering module is configured to: when the mobile node MAG is used, buffering the first message received before the first transmission tunnel is established;

When the packet forwarding module is used as the mobile node MAG, the first packet is forwarded after the first transmission tunnel is established.

Optionally, corresponding to the foregoing Embodiment 3 and Embodiment 5, the address query request further carries node information of the mobile node (MN) and mobile access gateway information, where the mobile access gateway information of the MN is mobile The address of the node MAG, or the proxy care-of address assigned by the mobile node MAG to the MN; as shown in FIG. 11, on the basis of the MAG shown in FIG. 9, when the MAG is the peer node MAG corresponding to the CN , Also includes:

a query request receiving module, configured to receive an address query request sent by the mapping server, and a query response sending module, configured to send an address query to the mobile node MAG corresponding to the MN according to the mobile access gateway information of the MN in the address query request Reply message.

Further, corresponding to the embodiments 2 to 3, the address query response message is sent by the mapping server or the peer node MAG. On the basis of the MAG shown in FIG. 10, the MAG further includes a mapping relationship maintenance module. And the mapping relationship between the node information of the CN and the mobile access gateway information is saved according to the address query response message; the packet forwarding module is further configured to: before the forwarding The packet encapsulates the outer tunnel address, and the outer source address of the encapsulation is the mobile access gateway information of the MN, and the destination address is the mobile access gateway information of the CN.

Optionally, corresponding to the foregoing Embodiment 3 and Embodiment 5, when the same as the peer node MAG: the transmission tunnel establishing module is further configured to establish, according to the mobile access gateway information of the MN in the address query request, a second transmission tunnel to the mobile node MAG corresponding to the MN; the mapping relationship maintenance module is further configured to save a mapping relationship between the node information of the MN and the mobile access gateway information according to the address query request.

Functional modules that are particularly relevant to the present invention of the mapping server of the present invention are described below.

18 As shown in FIG. 12, in particular, in connection with the present invention, the mapping server of the present invention includes:

The query request receiving module is configured to receive an address query request sent by the mobile node MAG corresponding to the mobile node, where the node information of the peer node (CN) is carried;

a binding relationship maintenance module, configured to save a binding relationship, where the binding relationship between the node information of the CN and the mobile access gateway information is included;

a binding relationship query module, configured to query the saved binding relationship, and obtain information about the mobile access gateway corresponding to the node information of the peer node;

a query request processing module, configured to send an address query response message to the mobile node MAG, where the mobile access gateway information of the CN is carried; or, to correspond to the CN according to the mobile access gateway information of the CN The peer node MAG forwards the address query request.

Optionally, corresponding to the foregoing Embodiments 4 and 5, the address query request further carries a first message, and the destination address of the first document is node information of the CN.

In particular, corresponding to the foregoing embodiment 4, as shown in FIG. 13, on the basis of the mapping server shown in FIG. 12, the mapping server further includes a packet forwarding module, configured to access the gateway information according to the CN Forwarding the first packet to the peer node MAG.

Corresponding to Embodiment 1, as shown in FIG. 14, on the basis of the mapping server shown in FIG. 12, the mapping server further includes:

a proxy binding update message receiving module, configured to receive a proxy binding update message sent by a mobile node (MN) mobile access gateway (MAG);

a home network prefix allocation module, configured to allocate a home network prefix to the MN;

a proxy binding confirmation message sending module, configured to reply to the mobile node MAG with a proxy binding acknowledgement message, where the message carries a home network prefix assigned to the MN;

The binding relationship saved in the binding relationship maintenance module is a binding relationship between the home network prefix and the proxy care-of address of the MN determined according to the allocated home network prefix and the proxy binding update message.

In addition, the present invention also provides a message forwarding path management system including a mobile access gateway (MAG) and a mapping server as described above.

19 In general, the home network prefix is the first 64 bits of the home address. In view of this special correspondence between the home network prefix and the home address, the network element (such as the mapping server or MAG) that knows the home address can infer the corresponding home network prefix.

Compared with the prior art, the technical solution provided by the embodiment of the present invention has the following advantages: By querying the mapping server for the mobile access gateway information of the opposite node, the packet does not need to be forwarded through a fixed anchor point, thereby optimizing data forwarding. The path reduces the data transmission delay.

One of ordinary skill in the art will appreciate that all or a portion of the above steps may be accomplished by a program instructing the associated hardware, such as a read-only memory, a magnetic disk, or an optical disk. Alternatively, all or part of the steps of the above embodiments may also be implemented using one or more integrated circuits. Correspondingly, each module in the foregoing embodiment may be implemented in the form of hardware, or may be implemented in the form of a software function module. The invention is not limited to any specific combination of hardware and software.

Industrial Applicability The packet forwarding path management method, the network element, and the system in the embodiment of the present invention query the mobile access gateway information of the opposite node (CN) through the mobile access gateway (MAG) attached by the mobile node (MN), thereby The mobile access gateway implements packet forwarding between the MN and the CN to solve the traffic forwarding bottleneck caused by the LMA.

20

Claims

Claim

A packet forwarding path management method, the method comprising:

The first mobile access gateway (MAG) sends an address query request to the mapping server, where the address query request carries node information of the peer node (CN);

2. The method according to claim 1, wherein, before the first MAG sends the address query request, the method further includes: receiving, by the first MAG, the first report sent by the mobile node (MN) The first MAG establishes a first transmission tunnel to the second MAG, and performs the first packet forwarding by using the first transmission tunnel.

The method of claim 1, wherein, before the first MAG sends the address query request, the method further includes: receiving, by the first MAG, a first message sent by a mobile node (MN), where The destination address of the first message is the home address of the CN; the address query request further carries the first message; after the mapping server queries the mobile access gateway information of the CN, directly to the The second MAG forwards the first message or forwards the first message to the second MAG by using the address query message.

The method of claim 1, wherein the address query request further carries the node information of the MN and the mobile access gateway information; after the second MAG receives the address query request message, according to the The mobile access gateway information of the MN is established to the second transmission tunnel of the first MAG, and the mapping relationship between the node information of the MN and the mobile access gateway information is saved.

5. The method of claim 1, wherein the first MAG receives the address query

twenty one After the response message, the method further includes: the first MAG saves a mapping relationship between the node information of the CN and the mobile access gateway information; and the first MAG encapsulates the received first packet according to the mapping relationship. After the tunnel address is forwarded, the outer source address of the encapsulated first packet is the mobile access gateway information of the MN, and the destination address is the mobile access gateway information of the CN.

The method according to claim 5, wherein, after receiving the encapsulated first message, the second MAG establishes a second transmission to the first MAG according to the mobile access gateway information of the MN. Tunneling, and storing a mapping relationship between the node information of the MN and the mobile access gateway information.

The method of claim 1, wherein the binding cache table includes a plurality of binding cache entries, and the binding cache entry is generated when the corresponding MN is registered, the MN The registration process includes:

The mapping server returns a proxy binding acknowledgement message to the MAG, carrying a home network prefix assigned to the MN;

8. A mobile access gateway (MAG), as a mobile node MAG corresponding to a mobile node (MN), the MAG includes:

The query response receiving module is configured to: receive an address query response message, and the address query

twenty two The response message carries the mobile access gateway information of the CN.

9. The MAG of claim 8, wherein the MAG further comprises:

a transmission tunnel establishing module, configured to: when the mobile node is a MAG, establish a first transmission tunnel to the opposite node MAG corresponding to the CN according to the mobile access gateway information of the CN in the address query response message;

The MAG of claim 8, wherein the address query request further carries the node information of the mobile node (MN) and the mobile access gateway information; and the MAG corresponding to the CN corresponding to the CN, the MAG further includes:

The MAG of claim 8 or 9, wherein the address query response message is sent by the mapping server or the peer node MAG.

The MAG of claim 11, wherein the MAG further comprises a mapping relationship maintenance module, as the mobile node MAG:

The mapping relationship maintenance module is configured to: save a mapping relationship between the node information of the CN and the mobile access gateway information according to the address query response message;

The MAG according to claim 11, wherein, when the peer node is a MAG, the transport tunnel establishing module is further configured to: query the MN in the request according to the address

twenty three The gateway information is dynamically accessed, and a second transmission tunnel to the mobile node MAG corresponding to the MN is established.

The MAG according to claim 13, wherein, when the peer node is a MAG, the mapping relationship maintenance module is further configured to: save the node information of the MN and the mobile access gateway information according to the address query request Mapping relations.

15. A mapping server, the mapping server comprising:

The query request receiving module is configured to: receive an address query request sent by the mobile node MAG corresponding to the mobile node, and carry node information of the opposite node (CN);

The mapping server according to claim 15, wherein the address query request further carries a first message, and the destination address of the first message is node information of the CN.

The mapping server according to claim 16, wherein the mapping server further includes a message forwarding module, configured to: forward the first report to the opposite node MAG according to the mobile access gateway information of the CN Text.

The mapping server according to claim 15, wherein the mapping server further comprises: a proxy binding update message receiving module, configured to: receive a proxy binding sent by a mobile node (MN) mobile access gateway (MAG) Update message

The binding relationship saved by the binding relationship maintenance module is based on the assigned home network prefix and the

twenty four The binding relationship between the home network prefix and the proxy care-of address of the MN saved by the proxy binding update message.

A message forwarding path management system, comprising the mobile access gateway (MAG) according to any one of claims 8 to 14.

The system according to claim 19, wherein the system further comprises the mapping server according to any one of claims 15 to 18.