CN102916878B - Send method and the border router of message - Google Patents

Abstract

The embodiment of the present invention provides a kind of method and the border router that send message, the method comprises the first message for setting up the first pseudo-circuit PW that ASBR2 receives ASBR1 transmission, according to a FEC TLV, first source IP address and the first corresponding relation determine the address of ASBR3 adjacent with the 3rd AS in the 2nd AS, and according to a FEC TLV, first source IP address and the second corresponding relation determine the address of ASBR4 adjacent with the 2nd AS in the 3rd AS, ASBR2 sends to ASBR3 the border router that the first message achieves to next AS and sends the first message for setting up a PW, set up the head node of PW without the need to obtaining the border router information of whole network, thus the border router information of non-adjacent AS overcomes when can not be known, be difficult to the shortcoming realizing multi-segment pseudo-wires road.

Description

Method of sending packets and border routers

technical field

The embodiment of the present invention relates to the technical field of communication, and in particular to a method for sending a message and a border router.

Background technique

With the continuous development of L2VPN technology, more and more L2VPN services are used in operators, and the application scenarios are more and more diverse.

In general, L2VPN services can be implemented by establishing a pseudowire (Pseudowire, hereinafter referred to as: PW) between terminal edge network devices (TerminatingProvider Edge, hereinafter referred to as: T-PE). Multi-Segment Pseudowire (hereinafter referred to as: MS-PW), when configuring MS-PW, various manufacturers widely use manual configuration to implement, but manual configuration has many inconveniences in operation and maintenance, such as when When there are a large number of L2VPN services, configuration, maintenance, and modification are very cumbersome processes, so the dynamic MS-PW solution emerges as the times require.

The existing technology provides a technical solution for forwarding equivalence class (Forwarding Equivalence Class, hereinafter referred to as: FEC) packets by hop-by-hop forwarding by configuring Explicit Routing Hop (Explicit Routing Hop) to reach the peer T-PE. , Figure 1 is a schematic diagram of implementing dynamic MS-PW in the prior art. ) AS1, AS2...ASN has N ASs in total, among which T-PE1 is located in AS1, T-PE2 is located in ASN, the border router (Autonomous Systems Border Router, hereinafter referred to as: ASBR) ASBR1 is the border router of AS1, ASBR2 and ASBR3 are Two border routers of AS2, ASBRN is the border router of ASN. First, T-PE1 generates FEC message 0, which includes the border routers in the entire pseudowire and the border network device information of the destination pseudowire terminal, such as ASBR1, ASBR2, ASBR3...ASBR2, T-PE2. T-PE1 sends FEC packet 0 to the border router ASBR1 of AS1 in the autonomous domain. After receiving FEC packet 0, ASBR1 deletes itself from packet 0, updates it to packet 1, and forwards packet 1 to the next A border router, that is, the border router ASBR2 of the autonomous domain AS2. After receiving message 1, ASBR2 deletes itself from the message, updates it to message 2, and forwards message 2 to the next border router, that is, the autonomous The border router ASBR3 of the domain AS2 and the border router of the autonomous domain omitted in the middle repeat the above actions until the border router ASBRN connected to the peer T-PE2 receives the message N-1 forwarded by the border router of the previous autonomous domain, ASBRN Delete itself from the message, update it to message N, and directly submit the message N to the peer T-PE2, and the peer T-PE2 performs content matching according to the receiving policy. If the match is successful, receive the message, and the match fails. Just discard.

In the process of realizing the present invention, the inventor finds that there are at least the following problems in the prior art:

It can be known from the above prior art that in order to ensure the normal communication of the MS-PW, T-PE1 or T-PE2 must know the border router information of all autonomous domains in the entire MS-PW path in advance. In the scenario of crossing multiple autonomous domains, In some cases, the border router information of non-adjacent autonomous domains cannot be known. At this time, the message used to establish a PW may not be sent from one AS to another AS, so that the dynamic MS-PW technology will not be implemented.

Contents of the invention

The embodiment of the present invention provides a method for sending a message and a border router, which are used to establish a multi-segment pseudo-wire.

The first aspect of the present invention provides a method for sending messages, the method is applied to a network including at least a first autonomous domain (AS), a second AS, and a third AS, and the first AS and the second AS Two ASs are adjacent, the third AS is adjacent to the second AS, and the method includes:

The border router (ASBR2) adjacent to the first AS in the second AS receives the first message for establishing the first pseudowire PW sent by the ASBR1 adjacent to the second AS in the first AS. A message, the first message includes a first forwarding equivalence class type length value (TLV) and a first path information TLV, and the first path information TLV includes a first source IP address and a first destination IP address, The first source IP address includes an address of a first PE, the first destination IP address includes an address of a second PE, the first PE is a first end point of the first PW, and the second PE being the second endpoint of the first PW;

When the second PE is outside the second AS, the ASBR2 determines according to the first forwarding equivalence class TLV, the first source IP address, and the first corresponding relationship The address of the ASBR3 adjacent to the third AS, the first correspondence includes the correspondence between the first forwarding equivalence class TLV, the first source IP address, and the address of the ASBR3; and, the ASBR2 determines the address of ASBR4 adjacent to the second AS in the third AS according to the first forwarding equivalence class TLV, the first source IP address, and a second correspondence, and the second correspondence including the correspondence between the first forwarding equivalence class TLV, the first source IP address, and the address of the ASBR4;

The ASBR2 sends a first packet to the ASBR3, and the first path information TLV of the first packet sent by the ASBR2 to the ASBR3 includes the first source IP address and the address of the ASBR4.

In the first possible implementation manner according to the first aspect, the specific implementation is as follows: the first correspondence and the second correspondence are configured in the ASBR2, or the ASBR2 acquires the The first corresponding relationship and the second corresponding relationship.

In a second possible implementation manner according to the first aspect, the specific implementation is: the ASBR2 acquiring the first correspondence and the second correspondence through learning includes:

The ASBR2 receives a second packet sent by the second PE for establishing the first PW, the second packet includes a second forwarding equivalence class TLV and a second path information TLV, and the second The path information TLV includes a second source IP address, a second destination IP address, the address of the ASBR1, the address of the ASBR2, the address of the ASBR3, and the address of the ASBR4, and the second source IP address is the The address of the second PE, the second destination IP address is the address of the first PE;

When the ASBR2 determines that the first packet and the second packet are both packets used to establish the first PW and determines that the ASBR3 is the second AS, it is related to the third AS After the adjacent ASBR, generate the first corresponding relationship;

The ASBR2 is connected to the second AS after determining that the first message and the second message are both messages used to establish the first PW and determining that the ASBR4 is the third AS After the ASBR, generate the second corresponding relationship.

The second aspect of the present invention provides a method for sending packets, the method is applied in a network including at least a first AS, a second AS and a third AS, the first AS is adjacent to the second AS, The second AS is adjacent to the third AS, the second AS includes multiple pseudowires configured in a static manner, and the method includes:

The ASBR2 adjacent to the first AS in the second AS receives the first packet for establishing the first PW sent by the ASBR1 adjacent to the second AS in the first AS, and the second AS A message includes a first forwarding equivalence class type length value (TLV) and a first path information TLV, the first path information TLV includes a first source IP address and a first destination IP address, and the first source IP The address includes the address of the first PE, the first destination IP address includes the address of the second PE, the first PE is the first endpoint of the first PW, and the second PE is the first PW The second endpoint of the first path information TLV, the value of the U bit and the F bit in the first path information TLV are both 1, and the ASBR2 is an endpoint of the statically configured multi-segment pseudowire;

The ASBR2 forwards the first packet including the first path information TLV according to the forwarding rule of the statically configured multi-segment pseudowire after determining that the values of the U bit and the F bit are both 1.

A third aspect of the present invention provides a method for sending packets, the method is applied to a network including a first AS, a second AS, and a third AS, the first AS is adjacent to the second AS, and the The second AS is adjacent to the third AS, the first AS includes a statically configured multi-segment pseudowire, and the method includes:

ASBR2 adjacent to the first AS in the second AS receives a first packet for establishing a first PW from ASBR3 adjacent to the third AS in the second AS, and the first The message includes a first forwarding equivalence class type length value (TLV) and a first path information TLV, and the first path information TLV includes the address of the ASBR3 and the address of the third AS adjacent to the second AS The address of the ASBR4;

The ASBR2 receives a second message for establishing the first PW from the ASBR1 adjacent to the second AS in the first AS, the second message includes a second forwarding equivalence class TLV, and the ASBR1 is an endpoint of the statically configured multi-segment pseudowire;

After the ASBR2 determines that both the first message and the second message are used to establish the first PW, it adds a second path information TLV to the second message, and the second path information TLV includes the address of said ASBR4;

The ASBR2 sends the second packet carrying the second path information TLV to the ASBR3, wherein the address of the ASBR4 is used to indicate that the ASBR3 will carry all the packets carrying the second path information TLV Send the second packet to the ASBR4.

In a first possible implementation manner according to the third aspect, the specific implementation is: the method further includes:

If the first forwarding equivalence class TLV matches the second forwarding equivalence class TLV, determine that both the first packet and the second packet are used to establish a first PW;

or,

If the first forwarding equivalence class TLV matches the second forwarding equivalence class TLV and the compatible flag bit in the first path information TLV is set, determine that the first packet and the The second packets are all used to establish the first PW.

In a second possible implementation manner according to the third aspect, it is specifically implemented as follows: the first path information TLV further includes a first source IP address and a first destination IP address, and the first source IP address is the first The address of the PE, the first destination IP address is the address of the second PE, the first PE is the first end point of the first PW, and the second PE is the second end point of the first PW ;

The second path information TLV further includes a second source IP address and a second destination IP address, the second source IP address is the address of the second PE, and the second destination IP address is the address of the first PE.

A fourth aspect of the present invention provides a border router, which is applied to a network including at least a first autonomous domain (AS), a second AS, and a third AS, and the first AS is adjacent to the second AS, so The third AS is adjacent to the second AS, the border router is located in the second AS, and is adjacent to the first AS, and the border router includes:

a receiving unit, configured to receive a first message for establishing a first pseudowire (PW) sent by an ASBR1 adjacent to the second AS in the first AS, where the first message includes a first forwarding The equivalence class type length value forwards the equivalence class (TLV) and the first path information TLV, the first path information TLV includes the first source IP address and the first destination IP address, and the first source IP address includes the first The address of a PE, the first destination IP address includes the address of a second PE, the first PE is the first end point of the first PW, and the second PE is the second end point of the first PW endpoint;

An address obtaining unit, configured to determine the second PE according to the first forwarding equivalence class TLV, the first source IP address, and the first correspondence when the second PE is outside the second AS. an address of ASBR3 adjacent to the third AS in the AS, the first correspondence includes a correspondence between the first forwarding equivalence class TLV, the first source IP address, and the address of ASBR3; and , determining the address of the ASBR4 adjacent to the second AS in the third AS according to the first forwarding equivalence class TLV, the first source IP address, and a second correspondence, the second correspondence including the correspondence between the first forwarding equivalence class TLV, the first source IP address, and the address of the ASBR4;

A sending unit, configured to send a first message to the ASBR3, the first path information TLV of the first message sent to the ASBR3 by the ASBR2 includes the first source IP address and the address of the ASBR4 .

In a first possible implementation manner according to the fourth aspect, the specific implementation is as follows: the border router further includes:

a storage unit, configured to store the configured first correspondence and the second correspondence; or,

A learning unit, configured to acquire the first corresponding relationship and the second corresponding relationship through learning.

In a second possible implementation manner according to the fourth aspect, the specific implementation is: the first receiving unit is further configured to receive a second message sent by the second PE for establishing the first PW, The second message includes a second forwarding equivalence class TLV and a second path information TLV, and the second path information TLV includes a second source IP address, a second destination IP address, the address of the ASBR1, the address of the ASBR2 address, the address of the ASBR3 and the address of the ASBR4, the second source IP address is the address of the second PE, and the second destination IP address is the address of the first PE;

The learning unit is specifically configured to determine that both the first message and the second message are messages used to establish the first PW and determine that the ASBR3 is the second AS and that the After the third AS is adjacent to the ASBR, generate the first correspondence; and, after determining that both the first packet and the second packet are packets used to establish the first PW and determining the After the ASBR4 is the ASBR connected to the second AS in the third AS, the second corresponding relationship is generated.

A fifth aspect of the present invention provides a border router, which is applied to a network including at least a first AS, a second AS, and a third AS, the first AS is adjacent to the second AS, and the second AS and the The third AS is adjacent, the second AS includes statically configured multi-segment pseudowires, the border router is located in the second AS and is adjacent to the first AS, and the border router include:

A receiving unit, configured to receive a first message for establishing a first PW sent by an ASBR1 adjacent to the second AS in the first AS, where the first message includes a first forwarding equivalence class type length value (TLV) and first path information TLV, the first path information TLV includes a first source IP address and a first destination IP address, the first source IP address includes the address of the first PE, and the first A destination IP address includes an address of a second PE, the first PE is the first end point of the first PW, the second PE is the second end point of the first PW, and the first path information The values of the U bit and the F bit in the TLV are both 1, and the ASBR2 is an endpoint of the statically configured multi-segment pseudowire;

The sending unit is configured to forward the first message including the first path information TLV according to the statically configured multi-segment pseudowire forwarding rules after determining that both the U bit and the F bit have values of 1.

A sixth aspect of the present invention provides a border router, which is applied to a network including a first AS, a second AS, and a third AS, the first AS is adjacent to the second AS, and the second AS and the second AS are The third AS is adjacent to the third AS, the first AS includes a statically configured multi-segment pseudowire, the border router is located in the second AS, and is adjacent to the first AS, and the border router includes:

An acquiring unit, configured to receive a first message for establishing a first PW from an ASBR3 adjacent to the third AS in the second AS, where the first message includes a length of a first forwarding equivalence class type a value TLV and a first path information TLV, the first path information TLV including the address of the ASBR3 and the address of the ASBR4 adjacent to the second AS in the third AS;

a receiving unit, configured to receive a second message for establishing a first PW from an ASBR1 adjacent to the second AS in the first AS, where the second message includes a second forwarding equivalence class TLV, The ASBR1 is an endpoint of the statically configured multi-segment pseudowire;

A message converting unit, configured to add a second path information TLV to the second message after determining that both the first message and the second message are used to establish the first PW, the The second path information TLV includes the address of the ASBR4;

a sending unit, configured to send the second packet carrying the second path information TLV to the ASBR3, wherein the address of the ASBR4 is used to indicate that the ASBR3 will carry the second path information TLV Send the second packet to the ASBR4.

In a first possible implementation manner according to the sixth aspect, it is specifically implemented as follows: the border router further includes:

A determining unit, configured to determine that both the first packet and the second packet are used to establish the first PW; or, if the first forwarding equivalence class TLV matches the second forwarding equivalence class TLV and the compatible flag bit in the first path information TLV is set, then determine Both the first packet and the second packet are used to establish the first PW.

In a second possible implementation manner according to the sixth aspect, it is specifically implemented as follows: the first path information TLV further includes a first source IP address and a first destination IP address, and the first source IP address is the first The address of the PE, the first destination IP address is the address of the second PE, the first PE is the first end point of the first PW, and the second PE is the second end point of the first PW ;

The second path information TLV further includes a second source IP address and a second destination IP address, the second source IP address is the address of the second PE, and the second destination IP address is the address of the first PE.

In the method for sending packets and the border router provided by the embodiment of the present invention, ASBR2 determines the address of ASBR3 adjacent to the third AS in the second AS according to the first forwarding equivalence class TLV, the first source IP address and the first correspondence , and determine the address of ASBR4 adjacent to the second AS in the third AS according to the first forwarding equivalence class TLV, the first source IP address, and the second correspondence. Realized sending the first message for establishing the first PW to the border router of the next AS, and the head node of establishing the PW does not need to obtain the border router information of the entire network, thus overcoming the fact that the border router information of non-adjacent ASs cannot be known In the case of , it is difficult to realize the disadvantage of multi-segment pseudowire.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained according to these drawings without any creative effort.

FIG. 1 is a schematic diagram of implementing dynamic MS-PW in the prior art;

FIG. 2 is a network structure diagram of Embodiment 1 of the method for sending messages according to the present invention;

FIG. 3 is a schematic flowchart of Embodiment 1 of the method for sending a message in the present invention;

FIG. 4 is a schematic flow diagram of Embodiment 2 of the method for sending a message in the present invention;

FIG. 5 is a schematic flowchart of Embodiment 3 of the method for sending a message according to the present invention;

FIG. 6 is a schematic diagram of a message structure in Embodiment 4 of the method for sending a message according to the present invention;

FIG. 7 is a schematic flowchart of Embodiment 4 of the method for sending a message according to the present invention;

FIG. 8 is a schematic structural diagram of Embodiment 1 of the border router of the present invention;

FIG. 9 is a schematic structural diagram of Embodiment 2 of the border router of the present invention;

FIG. 10 is a schematic structural diagram of Embodiment 3 of the border router of the present invention;

FIG. 11 is a schematic structural diagram of Embodiment 4 of the border router of the present invention;

FIG. 12 is a schematic structural diagram of Embodiment 4 of the border router of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Figure 2 is a network structure diagram of Embodiment 1 of the method for sending messages according to the present invention. The network of this embodiment includes at least a first autonomous domain (AS), a second AS, and a third AS. In order to express the embodiment of the present invention more clearly method, this embodiment takes a network including three autonomous domains as an example, where the first AS is adjacent to the second AS, and the third AS is adjacent to the second AS. The first AS includes the first PE and ASBR1 adjacent to the second AS. The second AS includes ASBR2 and ASBR3. ASBR2 is adjacent to the first AS, ASBR3 is adjacent to the third AS, and the third AS includes ASBR4 and the second AS. PE, where ASBR4 is adjacent to the second AS.

Fig. 3 is a schematic flow chart of Embodiment 1 of the method for sending a message according to the present invention. The method of this embodiment is applied to the network shown in Fig. 2, and the method of this embodiment includes:

Step 301: A border router (ASBR2) adjacent to the first AS in the second AS receives a first message for establishing a first pseudowire (PW) sent by an ASBR1 adjacent to the second AS in the first AS.

Specifically, the first message includes a first FEC type length value (Type Length Value, hereinafter referred to as: TLV) and a first path information TLV, and the first path information TLV includes a first source IP address and a first destination IP address, The first source IP address includes the address of the first PE, the first destination IP address includes the address of the second PE, the first PE is the first end point of the first PW, and the second PE is the second end point of the first PW.

Step 302: ASBR2 determines the address of ASBR3 adjacent to the third AS in the second AS according to the first FEC TLV, the first source IP address and the first correspondence.

When the second PE is outside the second AS, this step is to obtain the ASBR adjacent to the next AS domain in this AS domain, that is, ASBR2 in this network obtains the address of ASBR3 adjacent to the next AS domain in this AS domain Specifically, the first correspondence includes a correspondence between the first FEC TLV, the first source IP address, and the address of ASBR3.

Step 303: ASBR2 determines the address of ASBR4 adjacent to the second AS in the third AS according to the first FEC TLV, the first source IP address and the second corresponding relationship.

The difference from step 302 is that this step is to obtain the ASBR of the next AS adjacent to the current AS domain, that is, the manner in which ASBR2 in the current network obtains the address of ASBR4 in the third AS domain. Specifically, the second correspondence includes the first Correspondence between the FEC TLV, the first source IP address, and the address of ASBR4.

Step 304: ASBR2 sends a first packet to ASBR3, and the first path information TLV of the first packet sent by ASBR2 to ASBR3 includes the first source IP address and the address of ASBR4.

It is worth noting that the method in this embodiment is not limited to the network of three ASs. For a network of multiple ASs, it is similar to the method including three AS networks. Those skilled in the art can follow the method shown in the above embodiment Informed, no more details here.

In this embodiment, ASBR2 determines the address of ASBR3 adjacent to the third AS in the second AS according to the first FECTLV, the first source IP address, and the first correspondence, and determines the address of ASBR3 adjacent to the third AS in the second AS according to the first FECTLV, the first source IP address, and The second correspondence determines the address of ASBR4 adjacent to the second AS in the third AS. Realized sending the first message for establishing the first PW to the border router of the next AS, and the head node of establishing the PW does not need to obtain the border router information of the entire network, thus overcoming the fact that the border router information of non-adjacent ASs cannot be known In the case of , it is difficult to realize the disadvantage of multi-segment pseudowire.

In the above embodiment, there are two possible ways for ASBR2 to obtain the first correspondence and the second correspondence:

Optionally, as a first possible implementation manner: the first correspondence and the second correspondence are configured in ASBR2 through user configuration.

Optionally, as a second possible implementation manner, the ASBR2 obtains the first corresponding relationship and the second corresponding relationship through learning.

ASBR2 obtains the first corresponding relationship and the second corresponding relationship through learning, including the following steps:

Step 1: ASBR2 receives the first packet sent by ASBR1.

When the first message does not contain the first corresponding relationship and the second corresponding relationship, ASBR2 waits for the second step of operation.

Step 2: ASBR2 receives the second message sent by the second PE for establishing the first PW.

Specifically, the second message is a message for reverse transmission, the second message includes the second FEC TLV and the second path information TLV, and the second path information TLV includes the second source IP address, the second destination IP address, the ASBR1 address, the address of ASBR2, the address of ASBR3 and the address of ASBR4, the second source IP address is the address of the second PE, and the second destination IP address is the address of the first PE.

Step 3: After ASBR2 determines that both the first message and the second message are used to establish the first PW and determines that ASBR3 is the ASBR adjacent to the third AS in the second AS, generate the first correspondence .

The first correspondence includes the correspondence between the first FEC TLV, the first source IP address, and the address of ASBR3.

Step 4: After ASBR2 determines that both the first message and the second message are used to establish the first PW and determines that ASBR4 is the ASBR connected to the second AS in the third AS, it generates the second corresponding relationship.

The foregoing second correspondence includes a correspondence between the first FEC TLV, the first source IP address, and the address of ASBR4.

The first corresponding relationship and the second corresponding relationship of ASBR2 in this embodiment are obtained through user configuration or ASBR2 learning, which realizes sending the first message for establishing the first PW to the border router of the next AS , the head node to establish a PW does not need to obtain the border router information of the entire network, thus overcoming the disadvantage that it is difficult to implement multi-segment pseudo-wires when the border router information of non-adjacent ASs is not known.

FIG. 4 is a schematic flow diagram of Embodiment 2 of the method for sending messages according to the present invention. The method of this embodiment is applied to the network structure shown in FIG. Applied to the method of compatible static configuration mode, as shown in Figure 4, the method of this embodiment includes:

Step 401: ASBR2 in the second AS adjacent to the first AS receives the first message for establishing the first PW sent by ASBR1 in the first AS adjacent to the second AS.

Specifically, the first message includes a first forwarding equivalence class type length value (FEC TLV) and a first path information TLV, the first path information TLV includes a first source IP address and a first destination IP address, and the first source The IP address includes the address of the first PE, the first destination IP address includes the address of the second PE, the first PE is the first endpoint of the first PW, the second PE is the second endpoint of the first PW, and the first path information Both the U bit and the F bit in the TLV have a value of 1, and both the U bit and the F bit in the first path information TLV have a value of 1, indicating that the device receiving this TLV can forward this TLV, and ASBR2 is statically configured An endpoint of a multisegment pseudowire.

Step 402: After determining that the values of the U bit and the F bit are both 1, the ASBR2 forwards the first message including the first path information TLV according to the statically configured multi-segment pseudowire forwarding rules.

The specific forwarding rules are not limited in the present invention.

In this embodiment, by indicating the U bit and the F bit in the first path information TLV, a compatible static configuration method is adopted to realize sending the first message for establishing the first PW to the border router of the next AS, The head node to establish a PW does not need to obtain the border router information of the entire network, thus overcoming the disadvantage that it is difficult to implement multi-segment pseudo-wires when the border router information of non-adjacent ASs is not known. In addition, there is no need to replace existing old equipment, so as to save costs and rationally utilize existing resources.

FIG. 5 is a schematic flowchart of Embodiment 3 of the method for sending a message according to the present invention. The method of the embodiment shown in FIG. 5 is applied to the network structure shown in FIG. 2 , wherein the first AS configures multi-segment pseudowires in a static manner. The steps of this embodiment include:

Step 501: ASBR2 adjacent to the first AS in the second AS receives a first message for establishing the first PW from ASBR3 adjacent to the third AS in the second AS.

Specifically, the first message includes the first forwarding equivalence class type length value (FEC TLV) and the first path information TLV, and the first path information TLV includes the address of ASBR3 and the ASBR4 adjacent to the second AS in the third AS the address of.

Step 502: ASBR2 receives the second message for establishing the first PW from the ASBR1 adjacent to the second AS in the first AS.

Specifically, the second packet includes the second FEC TLV, and ASBR1 is an endpoint of a statically configured multi-segment pseudowire.

Step 503: After determining that both the first packet and the second packet are used to establish the first PW, the ASBR2 adds the second path information TLV to the second packet.

Specifically, the second path information TLV includes the address of ASBR4.

Step 504: ASBR2 sends the second packet carrying the second path information TLV to ASBR3, wherein the address of ASBR4 is used to instruct ASBR3 to send the second packet carrying the second path information TLV to ASBR4.

In this embodiment, ASBR2 receives the first packet sent by ASBR3 for establishing the first PW and the second packet sent by ASBR1 for establishing the first PW, and adds the second path information TLV to the second packet , and send the second message carrying the second path information TLV to ASBR3, the address of ASBR4 in the second path information TLV instructs ASBR3 to send the second message carrying the second path information TLV to ASBR4, realizing the The border router of the next AS sends the second message for establishing the first PW. The head node of establishing the PW does not need to obtain the border router information of the entire network, thereby overcoming the situation that the border router information of non-adjacent ASs cannot be known. , it is difficult to realize the shortcoming of multi-segment pseudowire. And it is compatible with the static configuration of multiple pseudowires in the first AS domain.

In the foregoing embodiment, there are the following two possible implementation manners for determining that both the first packet and the second packet are used to establish the first PW.

Optionally, as a first possible implementation manner, if the first FEC TLV matches the second FECTLV, it is determined that both the first packet and the second packet are used to establish the first PW.

Wherein, the FEC TLV information may include information such as pseudo-wire type, pseudo-wire ID, and link interface parameters, and the above-mentioned information of the first FEC TLV is matched with the above-mentioned information of the second FEC TLV. If the matching is successful, the first report is determined. Both the message and the second message are used to establish the first PW.

Optionally, as another possible implementation, if the first FEC TLV matches the second FECTLV and the compatibility flag in the first path information TLV is set, then determine the first packet and the second packet Both are used to establish the first PW.

In the above embodiment, the first path information TLV also includes a first source IP address and a first destination IP address, the first source IP address is the address of the first PE, the first destination IP address is the address of the second PE, and the first destination IP address is the address of the second PE. One PE is the first end point of the first PW, and the second PE is the second end point of the first PW.

The second path information TLV also includes a second source IP address and a second destination IP address, the second source IP address is the address of the second PE, and the second destination IP address is the address of the first PE.

In this embodiment, the first FEC TLV is matched with the second FEC TLV or the first FEC TLV is matched with the second FEC TLV and the compatibility flag in the first path information TLV is set to determine the second FEC TLV. Both the first message and the second message are used to establish the first PW. Add the second path information TLV in the second message, and send the second message carrying the second path information TLV to ASBR3, and the address of ASBR4 in the second path information TLV indicates that ASBR3 will carry the second path information TLV The second packet sent to ASBR4 realizes sending the second packet for establishing the first PW to the border router of the next AS, and the head node for establishing the PW does not need to obtain the border router information of the entire network, thereby overcoming the When the border router information of the adjacent AS is not known, it is difficult to realize the disadvantage of multi-segment pseudowire. And it is compatible with the static configuration of multiple pseudowires by the first AS.

Fig. 6 is a schematic diagram of the message structure of Embodiment 4 of the method for sending a message according to the present invention, which shows that the first message for establishing the first PW sent by the first PE to the second PE is sent by different nodes The details of the carried FEC TLV and path information TLV. The content in the dotted box in Fig. 6 except FECTLV is the content included in the value (VALUE) part of the path information TLV.

Fig. 7 is a schematic flow diagram of Embodiment 4 of the method for sending messages according to the present invention; the method of the embodiment shown in Fig. 7 is applied to the network structure shown in Fig. 6; as shown in Fig. 7, the steps of this embodiment include:

Step 701: The first PE sends a first message for establishing the first PW to ASBR1 of the first AS, and the first message includes the first FEC TLV and the first path information TLV.

Specifically, the first TLV includes the first path information TLV includes the first source IP address and the first destination IP address, the first source IP address includes the address of the first PE, and the first destination IP address includes the address of the second PE , the first PE is the first end point of the first PW, and the second PE is the second end point of the first PW. The first path information TLV also includes the first corresponding relationship between the first FEC TLV, the first source IP address and the address of ASBR1, and the first path information TLV also includes the first FEC TLV, the first source IP address and the address of ASBR2 the second corresponding relationship. The first message is shown as message 61 in FIG. 6 .

The above-mentioned first correspondence and second correspondence may be configured in the first PE, or may be acquired through learning in other ways.

Step 702: ASBR1 receives the first FEC TLV and the first path information TLV for establishing the first PW sent by the first PE, and sends the first FEC TLV for establishing the first PW to ASBR2 according to the second correspondence in the first FEC TLV. A message, the first correspondence and the second correspondence in the first message are empty.

The first message is shown as message 62 in FIG. 6 .

Step 703: ASBR2 receives the first packet sent by ASBR1 for establishing the first pseudowire PW.

Step 704: ASBR2 obtains the first corresponding relationship and the second corresponding relationship in the first path information TLV through manual configuration, or obtains the first corresponding relationship and the second corresponding relationship through dynamic selection, or obtains the first corresponding relationship and the second corresponding relationship from the reverse message Obtain the first corresponding relationship and the second corresponding relationship.

Through step 704, the first message including the first correspondence and the second correspondence is obtained.

The first message is shown as message 63 in FIG. 6 .

Step 705: ASBR2 sends to ASBR3 a first message for establishing a first pseudowire PW.

Step 706: ASBR3 receives the first packet sent by ASBR2 for establishing the first pseudowire PW.

Step 707: ASBR3 sends the first packet to ASBR4 according to the second correspondence in the first packet sent by ASBR2 for establishing the first pseudowire PW, wherein the first correspondence in the first packet and The second correspondence is empty.

The first message is shown as message 64 in FIG. 6 .

Step 708: ASBR4 receives the first message sent by ASBR3 for establishing the first pseudo-wire PW, and finds that the first destination IP address is the IP address of the second PE adjacent to itself, then sends the first message to Second PE.

The first message is shown as message 64 in FIG. 6 .

In this embodiment, the first corresponding relationship and the second corresponding relationship in the first path information TLV are obtained through manual configuration, or the first corresponding relationship and the second corresponding relationship are obtained through dynamic selection, or from the reverse message Obtain the first corresponding relationship and the second corresponding relationship, so as to send the first message for establishing the first PW to the next AS, and the head node for establishing the PW does not need to obtain the border router information of the entire network, thereby overcoming the inconsistency When the border router information of the neighboring AS is not known, it is difficult to realize the disadvantage of multi-segment pseudowire. And it is compatible with the static configuration of multiple pseudowires by the first AS.

Fig. 8 is a schematic structural diagram of Embodiment 1 of the border router of the present invention. The border router of this embodiment is applied to a network including at least the first autonomous domain AS, the second AS, and the third AS, and the first AS and the second AS are connected to each other. The third AS is adjacent to the second AS, and the border router is located in the second AS and adjacent to the first AS. As shown in FIG. 8 , the border router in this embodiment includes a receiving unit 81, an address obtaining unit 82, and a sending unit 83, wherein the receiving unit 81 is used to receive the information sent by the ASBR1 adjacent to the second AS in the first AS. Establish the first packet of the first pseudowire PW, the first packet includes the first forwarding equivalence class type length value (FEC TLV) and the first path information TLV, and the first path information TLV includes the first source IP address and The first destination IP address, the first source IP address includes the address of the first PE, the first destination IP address includes the address of the second PE, the first PE is the first endpoint of the first PW, and the second PE is the first PW the second endpoint of .

The address acquisition unit 82 is configured to determine the address of the ASBR3 adjacent to the third AS in the second AS according to the first FEC TLV, the first source IP address, and the first correspondence when the second PE is outside the second AS, The first correspondence includes the correspondence between the first FEC TLV, the first source IP address, and the address of ASBR3; For the address of the adjacent ASBR4, the second correspondence includes the correspondence between the first FEC TLV, the first source IP address, and the address of ASBR4.

The sending unit 83 is configured to send the first packet to ASBR3, and the first path information TLV of the first packet sent by ASBR2 to ASBR3 includes the first source IP address and the address of ASBR4.

In this embodiment, the receiving unit and the sending unit may be physical interfaces, and the address obtaining unit may be at least one processor.

Each unit of the border router in this embodiment can be used to implement the technical solution of the method embodiment shown in FIG. 3 , and its implementation principle and technical effect are similar, and will not be repeated here.

Fig. 9 is a schematic structural diagram of the second embodiment of the border router of the present invention. Fig. 9 is based on the embodiment shown in Fig. 8, the border router further includes: a storage unit 84 or a learning unit 85; The configured first correspondence relationship and second correspondence relationship are stored; the learning unit 85 is configured to obtain the first correspondence relationship and the second correspondence relationship through learning.

In the above embodiment, the receiving unit 81 is further configured to receive the second message sent by the second PE for establishing the first PW, the second message includes the second FEC TLV and the second path information TLV, the second path information The TLV includes the second source IP address, the second destination IP address, the address of ASBR1, the address of ASBR2, the address of ASBR3, and the address of ASBR4. The second source IP address is the address of the second PE, and the second destination IP address is the address of the first PE. The address of the PE.

In the above embodiment, the learning unit 85 is specifically configured to determine that both the first packet and the second packet are packets used to establish the first PW and determine that ASBR3 is the ASBR adjacent to the third AS in the second AS. After that, generate the first corresponding relationship; and, after determining that the first message and the second message are both messages used to establish the first PW and determining that ASBR4 is the ASBR connected to the second AS in the third AS, generate Second Correspondence.

In this embodiment, the receiving unit and the sending unit may be physical interfaces.

Each unit of the border router in this embodiment can be used to implement the technical solution of the method embodiment shown in FIG. 3 , and its implementation principle and technical effect are similar, and will not be repeated here.

Fig. 10 is a schematic structural diagram of the third embodiment of the border router of the present invention; the border router of this embodiment is applied to a network including at least the first AS, the second AS and the third AS, the first AS is adjacent to the second AS, and the second AS is adjacent to the second AS. The second AS is adjacent to the third AS, the second AS includes multiple pseudowires configured in a static manner, and the border router is located in the second AS and is adjacent to the first AS. As shown in FIG. 10 , the border router in this embodiment includes: a receiving unit 101 and a sending unit 102; wherein, the receiving unit 101 is used to receive the information for establishing the first PW sent by the ASBR1 adjacent to the second AS in the first AS. The first message, the first message includes the first forwarding equivalence class type length value (FEC TLV) and the first path information TLV, the first path information TLV includes the first source IP address and the first destination IP address, The first source IP address includes the address of the first PE, the first destination IP address includes the address of the second PE, the first PE is the first end point of the first PW, the second PE is the second end point of the first PW, and the first PE is the second end point of the first PW. Both the U bit and the F bit in the path information TLV are 1, and ASBR2 is an endpoint of a statically configured multi-segment pseudowire.

The sending unit 102 is configured to forward the first message including the first path information TLV according to the statically configured multi-segment pseudowire forwarding rules after determining that the values of the U bit and the F bit are both 1.

In this embodiment, in the foregoing embodiments, the receiving unit and the sending unit may be physical interfaces.

Each unit in the border router of this embodiment can be used to execute the technical solution of the method embodiment shown in FIG. 4 , and its implementation principle and technical effect are similar, and will not be repeated here.

Figure 11 is a schematic structural diagram of the fourth embodiment of the border router of the present invention; the border router in this embodiment is applied to a network including the first AS, the second AS and the third AS, the first AS is adjacent to the second AS, and the second AS is adjacent to the second AS. The second AS is adjacent to the third AS, the first AS includes a statically configured multi-segment pseudowire, the border router is located in the second AS, and is adjacent to the first AS; as shown in Figure 11, the border router of this embodiment It includes: an acquiring unit 111 , a receiving unit 112 , a message converting unit 113 and a sending unit 114 .

Wherein, the obtaining unit 111 is configured to receive the first message for establishing the first PW from the ASBR3 adjacent to the third AS in the second AS, the first message includes the first forwarding equivalence class type length value (FECTLV) and the first path information TLV, the first path information TLV includes the address of ASBR3 and the address of ASBR4 adjacent to the second AS in the third AS.

The receiving unit 112 is configured to receive a second message for establishing the first PW from ASBR1 adjacent to the second AS in the first AS, the second message includes the second FEC TLV, and ASBR1 is a statically configured multi-segment FEC TLV. An endpoint of the line.

The packet conversion unit 113 is configured to add second path information TLV to the second packet after determining that both the first packet and the second packet are used to establish the first PW, and the second path information TLV includes the address of ASBR4.

The sending unit 114 is configured to send the second packet carrying the second path information TLV to ASBR3, wherein the address of ASBR4 is used to instruct ASBR3 to send the second packet carrying the second path information TLV to ASBR4.

In this embodiment, the receiving unit and the sending unit may be physical interfaces.

Each unit in the border router of this embodiment can be used to implement the technical solution of the method embodiment shown in FIG. 5 , and its implementation principle and technical effect are similar, and will not be repeated here.

FIG. 12 is a schematic structural diagram of the fourth embodiment of the border router of the present invention; FIG. 10 is based on the embodiment shown in FIG. 9 , further, the border router of this embodiment further includes: a determination unit 115 .

The determining unit 115 is configured to determine that both the first message and the second message are used to establish the first PW if the first FEC TLV matches the second FEC TLV; or, if the first FEC TLV matches the second FECTLV And if the compatibility flag in the first path information TLV is set, it is determined that both the first packet and the second packet are used to establish the first PW.

In the above embodiment, the first path information TLV also includes a first source IP address and a first destination IP address, the first source IP address is the address of the first PE, the first destination IP address is the address of the second PE, and the first destination IP address is the address of the second PE. One PE is the first end point of the first PW, and the second PE is the second end point of the first PW.

The second path information TLV also includes a second source IP address and a second destination IP address, the second source IP address is the address of the second PE, and the second destination IP address is the address of the first PE.

Each unit in the border router of this embodiment can be used to implement the technical solution of the method embodiment shown in FIG. 5 , and its implementation principle and technical effect are similar, and will not be repeated here.

Those skilled in the art can understand that all or part of the steps for implementing the above method embodiments can be completed by program instructions related hardware, such as a processor. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps including the above-mentioned method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other various media that can store program codes.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (14)

1. A method for sending messages, characterized in that the method is applied to a network including at least a first AS, a second AS, and a third AS, and the first AS and the second AS Adjacent, the third AS is adjacent to the second AS, the method includes: The border router ASBR2 adjacent to the first AS in the second AS receives the first message for establishing the first pseudowire PW sent by the ASBR1 adjacent to the second AS in the first AS , the first message includes a first forwarding equivalence class type length value TLV and a first path information TLV, the first path information TLV includes a first source IP address and a first destination IP address, and the first The source IP address includes the address of the first PE, the first destination IP address includes the address of the second PE, the first PE is the first end point of the first PW, and the second PE is the address of the second PE. a second endpoint of the PW; When the second PE is outside the second AS, the ASBR2 determines according to the first forwarding equivalence class TLV, the first source IP address, and the first corresponding relationship The address of the ASBR3 adjacent to the third AS, the first correspondence includes the first forwarding equivalence class TLV, the correspondence between the first source IP address and the address of the ASBR3, and the ASBR2 determines the address of ASBR4 adjacent to the second AS in the third AS according to the first forwarding equivalence class TLV, the first source IP address, and a second correspondence, and the second correspondence including the correspondence between the first forwarding equivalence class TLV, the first source IP address, and the address of the ASBR4; The ASBR2 sends a first packet to the ASBR3, and the first path information TLV of the first packet sent by the ASBR2 to the ASBR3 includes the first source IP address and the address of the ASBR4. 2. The method according to claim 1, wherein the first correspondence and the second correspondence are configured in the ASBR2, or the ASBR2 obtains the first correspondence through learning. Correspondence and the second correspondence. 3. The method according to claim 2, wherein the acquisition of the first correspondence and the second correspondence by the ASBR2 through learning comprises: The ASBR2 receives a second packet sent by the second PE for establishing the first PW, the second packet includes a second forwarding equivalence class TLV and a second path information TLV, and the second The path information TLV includes a second source IP address, a second destination IP address, the address of the ASBR1, the address of the ASBR2, the address of the ASBR3, and the address of the ASBR4, and the second source IP address is the The address of the second PE, the second destination IP address is the address of the first PE; When the ASBR2 determines that the first packet and the second packet are both packets used to establish the first PW and determines that the ASBR3 is the second AS, it is related to the third AS After the adjacent ASBR, generate the first corresponding relationship; The ASBR2 is connected to the second AS after determining that the first message and the second message are both messages used to establish the first PW and determining that the ASBR4 is the third AS After the ASBR, generate the second corresponding relationship. 4. A method for sending messages, characterized in that the method is applied to a network including at least a first AS, a second AS, and a third AS, and the first AS is connected to the second AS Adjacent, the second AS is adjacent to the third AS, the second AS includes multiple pseudowires configured in a static manner, and the method includes: The ASBR2 adjacent to the first AS in the second AS receives the first message for establishing the first pseudowire PW sent by the ASBR1 adjacent to the second AS in the first AS, and the The first message includes a first forwarding equivalence class type length value TLV and a first path information TLV, and the first path information TLV includes a first source IP address and a first destination IP address, and the first source IP The address includes the address of the first PE, the first destination IP address includes the address of the second PE, the first PE is the first endpoint of the first PW, and the second PE is the first PW The second endpoint of the first path information TLV, the value of the U bit and the F bit in the first path information TLV are both 1, and the ASBR2 is an endpoint of the statically configured multi-segment pseudowire; The ASBR2 forwards the first packet including the first path information TLV according to the forwarding rule of the statically configured multi-segment pseudowire after determining that the values of the U bit and the F bit are both 1. 5. A method for sending a message, characterized in that the method is applied to a network comprising a first autonomous domain AS, a second AS and a third AS, and the first AS is adjacent to the second AS , the second AS is adjacent to the third AS, the first AS includes a statically configured multi-segment pseudowire, and the method includes: The ASBR2 adjacent to the first AS in the second AS receives a first packet for establishing a first pseudowire PW from the ASBR3 adjacent to the third AS in the second AS, the The first message includes the first forwarding equivalence class type length value TLV and the first path information TLV, and the first path information TLV includes the address of the ASBR3 and the address of the third AS adjacent to the second AS The address of the ASBR4; The ASBR2 receives a second message for establishing the first PW from the ASBR1 adjacent to the second AS in the first AS, the second message includes a second forwarding equivalence class TLV, and the ASBR1 is an endpoint of the statically configured multi-segment pseudowire; After the ASBR2 determines that both the first message and the second message are used to establish the first PW, it adds a second path information TLV to the second message, and the second path information TLV includes the address of said ASBR4; The ASBR2 sends the second packet carrying the second path information TLV to the ASBR3, wherein the address of the ASBR4 is used to indicate that the ASBR3 will carry all the packets carrying the second path information TLV Send the second packet to the ASBR4. 6. The method according to claim 5, further comprising: If the first forwarding equivalence class TLV matches the second forwarding equivalence class TLV, determine that both the first packet and the second packet are used to establish a first PW; or, If the first forwarding equivalence class TLV matches the second forwarding equivalence class TLV and the compatible flag bit in the first path information TLV is set, determine that the first packet and the The second packets are all used to establish the first PW. 7. The method according to claim 5 or 6, wherein the first path information TLV further includes a first source IP address and a first destination IP address, and the first source IP address is the IP address of the first PE address, the first destination IP address is the address of the second PE, the first PE is the first endpoint of the first PW, and the second PE is the second endpoint of the first PW; The second path information TLV further includes a second source IP address and a second destination IP address, the second source IP address is the address of the second PE, and the second destination IP address is the address of the first PE. 8. A border router, characterized in that it is applied in a network including at least a first AS, a second AS, and a third AS, and the first AS is adjacent to the second AS, and the first AS is adjacent to the second AS. The three ASs are adjacent to the second AS, the border router is located in the second AS, and is adjacent to the first AS, and the border router includes: A receiving unit, configured to receive a first message for establishing a first pseudowire PW sent by an ASBR1 adjacent to the second AS in the first AS, where the first message includes a first forwarding equivalent class type length value TLV and first path information TLV, the first path information TLV includes a first source IP address and a first destination IP address, the first source IP address includes the address of the first PE, and the first A destination IP address includes an address of a second PE, the first PE is a first endpoint of the first PW, and the second PE is a second endpoint of the first PW; An address obtaining unit, configured to determine the second PE according to the first forwarding equivalence class TLV, the first source IP address, and the first correspondence when the second PE is outside the second AS. an address of ASBR3 adjacent to the third AS in the AS, the first correspondence includes a correspondence between the first forwarding equivalence class TLV, the first source IP address, and the address of ASBR3; and , determining the address of the ASBR4 adjacent to the second AS in the third AS according to the first forwarding equivalence class TLV, the first source IP address, and a second correspondence, the second correspondence including the correspondence between the first forwarding equivalence class TLV, the first source IP address, and the address of the ASBR4; A sending unit, configured to send a first message to the ASBR3, the first path information TLV of the first message sent to the ASBR3 by the ASBR2 includes the first source IP address and the address of the ASBR4 . 9. The border router according to claim 8, wherein the border router further comprises: a storage unit, configured to store the configured first correspondence and the second correspondence; or, A learning unit, configured to acquire the first corresponding relationship and the second corresponding relationship through learning. 10. The border router according to claim 9, wherein the receiving unit is further configured to receive a second packet sent by the second PE for establishing the first PW, the second packet The text includes the second forwarding equivalence class TLV and the second path information TLV, and the second path information TLV includes the second source IP address, the second destination IP address, the address of ASBR1, the address of ASBR2, the The address of ASBR3 and the address of ASBR4, the second source IP address is the address of the second PE, and the second destination IP address is the address of the first PE; The learning unit is specifically configured to determine that both the first message and the second message are messages used to establish the first PW and determine that the ASBR3 is the second AS and that the After the third AS is adjacent to the ASBR, generate the first correspondence; and, after determining that both the first packet and the second packet are packets used to establish the first PW and determining the After the ASBR4 is the ASBR connected to the second AS in the third AS, the second corresponding relationship is generated. 11. A border router, applied in a network comprising at least a first autonomous domain AS, a second AS and a third AS, the first AS is adjacent to the second AS, the second AS and the The third AS is adjacent, the second AS includes statically configured multi-segment pseudowires, the border router is located in the second AS, and is adjacent to the first AS, wherein the Border routers include: A receiving unit, configured to receive a first message for establishing a first pseudowire PW sent by an ASBR1 adjacent to the second AS in the first AS, where the first message includes a first forwarding equivalent class type length value TLV and first path information TLV, the first path information TLV includes a first source IP address and a first destination IP address, the first source IP address includes the address of the first PE, and the first A destination IP address includes an address of a second PE, the first PE is the first end point of the first PW, the second PE is the second end point of the first PW, and the first path information The values of the U bit and the F bit in the TLV are both 1, and the ASBR2 is an endpoint of the statically configured multi-segment pseudowire; The sending unit is configured to forward the first message including the first path information TLV according to the statically configured multi-segment pseudowire forwarding rules after determining that both the U bit and the F bit have values of 1. 12. A border router, applied to a network including a first autonomous domain AS, a second AS and a third AS, the first AS is adjacent to the second AS, the second AS and the first AS Three ASs are adjacent, the first AS includes a statically configured multi-segment pseudowire, the border router is located in the second AS and is adjacent to the first AS, and the border router is characterized in that include: An acquiring unit, configured to receive a first message for establishing a first pseudowire PW from an ASBR3 adjacent to the third AS in the second AS, where the first message includes a first forwarding equivalence class type length value TLV and first path information TLV, where the first path information TLV includes the address of ASBR3 and the address of ASBR4 adjacent to the second AS in the third AS; a receiving unit, configured to receive a second packet for establishing a first PW from an ASBR1 adjacent to the second AS in the first AS, where the second packet includes a second forwarding equivalence class TLV, The ASBR1 is an endpoint of the statically configured multi-segment pseudowire; A message converting unit, configured to add a second path information TLV to the second message after determining that both the first message and the second message are used to establish the first PW, the The second path information TLV includes the address of the ASBR4; a sending unit, configured to send the second packet carrying the second path information TLV to the ASBR3, wherein the address of the ASBR4 is used to indicate that the ASBR3 will carry the second path information TLV Send the second packet to the ASBR4. 13. The border router according to claim 12, further comprising: a determining unit, configured to determine that both the first packet and the second packet are used to establish the first forwarding equivalence class TLV and the second forwarding equivalence class TLV A PW; or, in the case that the first forwarding equivalence class TLV matches the second forwarding equivalence class TLV and the compatible flag bit in the first path information TLV is set, determine the Both the first packet and the second packet are used to establish the first PW. 14. The border router according to claim 12 or 13, wherein the first path information TLV further includes a first source IP address and a first destination IP address, and the first source IP address is the first PE address, the first destination IP address is the address of the second PE, the first PE is the first endpoint of the first PW, and the second PE is the second endpoint of the first PW; The second path information TLV further includes a second source IP address and a second destination IP address, the second source IP address is the address of the second PE, and the second destination IP address is the address of the first PE.