WO2024011982A1

WO2024011982A1 - Message forwarding method, system, network device, storage medium and program product

Info

Publication number: WO2024011982A1
Application number: PCT/CN2023/089293
Authority: WO
Inventors: 赵然晓
Original assignee: 华为技术有限公司
Priority date: 2022-07-12
Filing date: 2023-04-19
Publication date: 2024-01-18
Also published as: CN117440057A

Abstract

The present application belongs to the technical field of communications. Disclosed are a message forwarding method, a system, a network device, a storage medium and a program product. In the method, when a first forwarding node which is an edge node of an IPv6 network receives a first control message from a second forwarding node in the same IPv6 network, a second control message is generated on the basis of the first control message so as to send to a third forwarding node in the IPv4 network the second control message, the second control message being an IPv4 message; and when the second forwarding node does not have an IPv4 address, the second control message is expanded so as to carry in the second control message the IPv6 address of the second forwarding node. Therefore, when an intermediate node in an IPv6 network does not have an IPv4 address, the method provided in the embodiments of the present application can successfully notify a forwarding node in an IPv4 network about the situation of message forwarding.

Description

Message forwarding methods, systems, network equipment, storage media and program products

This application claims priority to the Chinese patent application with application number 202210818034.6 and the invention title "Message forwarding method, system, network equipment, storage medium and program product" submitted on July 12, 2022, the entire content of which is incorporated by reference. incorporated in this application.

Technical field

The embodiments of the present application relate to the field of communication technology, and in particular to a message forwarding method, system, network device, storage medium and program product.

Background technique

With the development of network technology, the sixth generation network protocol (Internet Protocol version 6, IPv6) network gradually replaces the IPv4 network. Among them, the IPv6 network includes an IPv6 dedicated (only) network. Intermediate nodes other than edge nodes in the IPv6 dedicated network are only configured with IPv6 addresses and are not configured with IPv4 addresses. In this scenario, if the intermediate node in the IPv6 private network receives a message sent from the forwarding node in the IPv4 network and determines that it cannot continue to forward the message, the intermediate node in the IPv6 private network needs to send a message to the forwarding node in the IPv4 network. The forwarding node announces the forwarding status of the message.

Contents of the invention

Embodiments of the present application provide a message forwarding method, system, network device, storage medium and program product, which can enable an intermediate node in an IPv6 private network to notify the forwarding node in an IPv4 network of message forwarding status. The technical solutions are as follows:

In a first aspect, a message forwarding method is provided. The method is applied to a message forwarding system. The message forwarding system includes a first forwarding node, a second forwarding node and a third forwarding node. The first forwarding node is an IPv6 network. The edge node, the second forwarding node is located in the IPv6 network, and the third forwarding node is located in the IPv4 network.

In this method, the first forwarding node receives the first message sent by the third forwarding node, and the first message is an IPv4 message. The first forwarding node generates a second message based on the first message, and sends the second message to the second forwarding node, where the second message is an IPv6 message. The first forwarding node receives the first control message sent by the second forwarding node. The first control message is an IPv6 message, and the first control message is used to notify the second forwarding node of forwarding the second message. When the first forwarding node determines that the second forwarding node does not have an IPv4 address, it generates a second control message based on the first control message and sends the second control message to the third forwarding node. The second control message is an IPv4 message, and the The second control packet carries the IPv6 address of the second forwarding node.

In this embodiment of the present application, when the first forwarding node of the edge node of the IPv6 network receives the first control message from the second forwarding node in the same IPv6 network, since the first control message is used to notify the second forwarding node to forward the first In the case of two messages, the second message is generated based on the first message from the IPv4 network. Therefore, when receiving the first control message, the first forwarding node needs to report to the sender of the first message (IPv4 network The third forwarding node in the server notifies the forwarding status of the packet. Based on this, when the first forwarding node receives the first control message, the first forwarding node generates a second control message based on the first control message, and the second control message is an IPv4 message to forward to the third party in the IPv4 network. The node sends a second control message. And when the second forwarding node does not have an IPv4 address, in order to achieve successful forwarding to the third forwarding node in the IPv4 network, The sending node notifies the packet forwarding situation of the second forwarding node in the IPv6 network. The embodiment of the present application extends the second control message to carry the IPv6 address of the second forwarding node in the second control message. Therefore, through the method provided by the embodiments of this application, the intermediate node in the IPv6 network can successfully notify the forwarding node in the IPv4 network of the packet forwarding status when it does not have an IPv4 address.

Based on the method provided in the first aspect, in a possible implementation manner, the first control message carries an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address. In this scenario, the first forwarding node determines that the second forwarding node does not have an IPv4 address. The implementation process is as follows: the first forwarding node parses the first control message to obtain the IPv6 dedicated network identifier; the first forwarding node determines the second forwarding node based on the IPv6 dedicated network identifier. The second forwarding node does not have an IPv4 address.

If the IPv6 network where the second forwarding node is located is an IPv6 private network, no IPv4 address is configured on the second forwarding node. In this scenario, in order to trigger the first forwarding node to use the method provided by the embodiment of the present application to notify the third forwarding node of the second forwarding node forwarding the second message, the second forwarding node can carry IPv6 in the first control message. The IPv6 dedicated network identifier of the network, so that the first forwarding node determines that the second forwarding node does not have an IPv4 address based on the IPv6 dedicated network identifier, and then uses the method provided by the embodiment of the present application to notify the third forwarding node of forwarding by the second forwarding node. The situation of the second message.

Based on the method provided in the first aspect, in a possible implementation manner, the first control message is a Network Control Message Protocol ICMP message. The first control message includes a first extension object, and the first extension object carries an IPv6 dedicated network identifier, or the first control message includes a first ICMP header, and the first ICMP header carries an IPv6 dedicated network identifier.

In this embodiment of the present application, when the first control message is an ICMP message, the ICMP message can be flexibly extended so that the extended ICMP message can carry the IPv6 dedicated network identifier. The flexibility of the embodiment of the present application is improved.

Based on the method provided in the first aspect, in a possible implementation manner, the implementation process for the first forwarding node to determine that the second forwarding node does not have an IPv4 address is: the first forwarding node obtains a locally stored IPv6 dedicated network identifier, and the IPv6 dedicated The network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address; the first forwarding node determines that the second forwarding node does not have an IPv4 address based on the IPv6 dedicated network identifier.

In this embodiment of the present application, the first forwarding node can also be configured in advance with the IPv6 dedicated network identifier corresponding to the IPv6 network where the second forwarding node is located, so that the first forwarding node can subsequently obtain the IPv6 dedicated network identifier directly from the local storage. Network identification, so that the first forwarding node determines that the second forwarding node does not have an IPv4 address based on the IPv6 dedicated network identification, and then uses the method provided by the embodiment of this application to notify the third forwarding node that the second forwarding node forwards the second message. Case. The flexibility of the embodiment of the present application is improved.

Based on the method provided in the first aspect, in a possible implementation manner, the first control message carries the IPv6 address of the second forwarding node. In this scenario, the first forwarding node generates the second control message based on the first control message. The first forwarding node obtains the IPv6 address of the second forwarding node from the first control message to generate the second control message.

Since the second control message needs to carry the IPv6 address of the second forwarding node, the first forwarding node needs to first obtain the IPv6 address of the second forwarding node when generating the second control message. In this embodiment of the present application, the first forwarding node can obtain the IPv6 address of the second forwarding node from the first control message or obtain the IPv6 address of the second forwarding node from local storage, which improves the flexibility of the embodiment of the present application. sex.

Based on the method provided in the first aspect, in a possible implementation manner, the first control message is a Network Control Message Protocol ICMP message, and the first control message includes a second extension object, and the second extension object carries the second forwarding node IPv6 address. In this scenario, the first forwarding node obtains the IPv6 address of the second forwarding node from the first control message. The process is: the first forwarding node obtains the IPv6 address of the second forwarding node from the second extension object.

Based on the method provided in the first aspect, in a possible implementation manner, the first control message is a Network Control Message Protocol ICMP message, and the first control message includes a second ICMP message header, and the second ICMP message header carries The IPv6 address of the second forwarding node. In this scenario, the implementation process of the first forwarding node obtaining the IPv6 address of the second forwarding node from the first control message is: the first forwarding node obtains the IPv6 address of the second forwarding node from the second ICMP message header.

In this embodiment of the present application, when the first control message is an ICMP message, the ICMP message can be flexibly extended by the above two implementation methods, so that the extended ICMP message can carry the IPv6 address of the second forwarding node. . The flexibility of the embodiment of the present application is improved.

Based on the method provided in the first aspect, in a possible implementation manner, the first control message includes a first IPv6 header, and the first IPv6 header carries the IPv6 address of the second forwarding node. In this scenario, the implementation process for the first forwarding node to obtain the IPv6 address of the second forwarding node from the first control message may be: the first forwarding node obtains the IPv6 address of the second forwarding node from the first IPv6 packet header.

Optionally, the IPv6 header of the first control message may carry the IPv6 address of the second forwarding node. Therefore, the first control message may also carry the IPv6 address of the second forwarding node without extending the first control message. The flexibility of the embodiment of the present application is improved.

Based on the method provided in the first aspect, in a possible implementation manner, the first forwarding node locally stores the IPv6 address of the second forwarding node. In this scenario, the implementation process of the first forwarding node generating the second control message based on the first control message is: the first forwarding node obtains the locally stored IPv6 address of the second forwarding node to generate the second control message based on the first control message and the second forwarding node. The IPv6 address generates a second control message.

In this embodiment of the present application, the first forwarding node can obtain the IPv6 address of the second forwarding node from the first control message or obtain the IPv6 address of the second forwarding node from local storage, which improves the flexibility of the embodiment of the present application. sex.

Based on the method provided in the first aspect, in a possible implementation manner, the second control message is a Network Control Message Protocol ICMP message. The second control message includes a third extension object, and the third extension object carries the IPv6 address of the second forwarding node. Alternatively, the second control message includes a third ICMP header, and the third ICMP header carries the second forwarding node. IPv6 address.

In this embodiment of the present application, the second control message can be flexibly expanded so that the second control message can carry the IPv6 address of the second forwarding node, which improves the application flexibility of the embodiment of the present application.

Based on the method provided in the first aspect, in a possible implementation manner, the second control message also carries an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address.

In this embodiment of the present application, the second control message may further carry an IPv6 dedicated network identifier, so that the third forwarding node can learn that the second forwarding node is a node in the IPv6 dedicated network. The flexibility of the embodiment of the present application is further improved.

Based on the method provided in the first aspect, in a possible implementation manner, the second control message is a Network Control Message Protocol ICMP message; wherein the second control message includes a fourth extension object, and the fourth extension object carries an IPv6 dedicated network identification, or the second control message includes a fourth ICMP header, and the fourth ICMP header carries the IPv6 dedicated network identification.

In this embodiment of the present application, the second control message can be flexibly expanded so that the second control message can carry the IPv6 dedicated network identifier, which improves the application flexibility of the embodiment of the present application.

Based on the method provided in the first aspect, in a possible implementation manner, the second forwarding node satisfies one of the following two conditions: the intermediate node in the IPv6 network where the second forwarding node is located does not have an IPv4 address configured; or, the second forwarding node Forward section The node is configured with an IPv4 address, but the IPv4 address of the second forwarding node is not used externally.

In the embodiment of the present application, in addition to being a node in an IPv6 private network, the second forwarding node without an IPv4 address may also include a node configured with an IPv4 address but the IPv4 address is not exposed to the outside world, further improving the performance of the embodiment of the present application. application flexibility.

Based on the method provided in the first aspect, in a possible implementation manner, both the first message and the second message carry the time-to-live TTL, and the first control message indicates that the second message reaches the second forwarding node when the second message reaches the second forwarding node. The TTL of the second packet has expired.

Based on the method provided by the embodiments of this application, the first control message and the second control message can be used to realize that when the TTL of forwarding a message from an IPv4 network expires and the second forwarding node in the IPv6 network is unable to continue forwarding the message, Successfully notify nodes in the IPv4 network of the packet forwarding error.

Based on the method provided in the first aspect, in a possible implementation manner, the first message and the second message are path tracing messages.

Based on the method provided by the embodiments of this application, it can also be realized that in the path tracing scenario across IPv6 networks, the second forwarding node in the IPv6 network successfully forwards the path tracing message to the IPv4 network when determining that the TTL of the path tracing message from the IPv4 network has timed out. The node advertises its own IPv6 address, so that the third forwarding node in the IPv4 network can track the IPv6 address of the second forwarding node. Improved path tracing success rate.

In a second aspect, a message forwarding method is provided. The method is applied to a message forwarding system. The message forwarding system includes a first forwarding node, a second forwarding node and a third forwarding node. The first forwarding node is a sixth forwarding node. The first generation network protocol IPv6 network is an edge node, the second forwarding node is located in the IPv6 network, and the third forwarding node is located in the fourth generation network protocol IPv4 network.

It should be noted that the technical effects of the method provided in the second aspect may refer to the technical effects of the method provided in the first aspect, and will not be described again here.

In this method, after sending the first message to the first forwarding node, the third forwarding node receives the second control message sent by the first forwarding node. The second control message is an IPv4 message and the second control message carries the second The IPv6 address of the forwarding node, the first message is an IPv4 message; the third forwarding node determines, based on the second control message, whether the second forwarding node forwards the first message.

Based on the method provided in the second aspect, in a possible implementation manner, after the third forwarding node determines that the second forwarding node forwards the first message based on the second control message, the method further includes:

The third forwarding node parses the second control message and obtains the IPv6 address of the second forwarding node;

The third forwarding node displays the IPv6 address of the second forwarding node.

Based on the method provided in the second aspect, in a possible implementation manner, the second control message is a Network Control Message Protocol ICMP message;

The second control message includes a third extension object, and the third extension object carries the IPv6 address of the second forwarding node. Alternatively, the second control message includes a third ICMP header, and the third ICMP header carries the IPv6 address of the second forwarding node. address.

Based on the method provided in the second aspect, in a possible implementation manner, after the third forwarding node determines that the first forwarding node forwards the first message based on the second control message, the method further includes:

The third forwarding node determines the IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address;

The third forwarding node displays the IPv6 private network identification.

Based on the method provided in the second aspect, in a possible implementation manner, the third forwarding node determines the IPv6 private network Logo, including:

The third forwarding node parses the second control message to obtain the IPv6 dedicated network identifier.

The second control message includes a fourth extension object, and the fourth extension object carries the IPv6 dedicated network identifier. Alternatively, the second control message includes a fourth ICMP header, and the fourth ICMP header carries the IPv6 dedicated network identifier.

Based on the method provided in the second aspect, in a possible implementation manner, the second control message indicates that when the first message reaches the second forwarding node, the time-to-live TTL of the first message times out.

Based on the method provided in the second aspect, in a possible implementation manner, the first message is a path tracing message.

In a third aspect, a message forwarding method is provided. The method is applied to a message forwarding system. The message forwarding system includes a first forwarding node and a second forwarding node. The first forwarding node is a sixth-generation network protocol IPv6 network. The edge node and the second forwarding node are located in the IPv6 network.

It should be noted that the technical effects of the method provided in the third aspect can also refer to the technical effects of the method provided in the first aspect, and will not be described again here.

In this method, the second forwarding node receives the second message sent by the first forwarding node, and the second message is an IPv6 message;

When the second forwarding node determines that it cannot continue to forward the second message and determines that the second message has an IPv4 header, it generates a first control message based on the second message, and the first control message instructs the second forwarding node to forward the second message. The situation of two messages, and the first control message indicates that the second forwarding node does not have an IPv4 address;

The second forwarding node sends the first control message to the first forwarding node.

Based on the method provided in the third aspect, in a possible implementation manner, the first control message carries an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address.

Based on the method provided in the third aspect, in a possible implementation manner, the first control message is a Network Control Message Protocol ICMP message;

The first control message includes a first extension object, and the first extension object carries an IPv6 dedicated network identifier. Alternatively, the first control message includes a first ICMP header, and the first ICMP header carries an IPv6 dedicated network identifier.

Based on the method provided in the third aspect, in a possible implementation manner, the first control message carries the IPv6 address of the second forwarding node.

The first control message includes a second extension object, and the second extension object carries the IPv6 address of the second forwarding node. Alternatively, the first control message includes a second ICMP header, and the second ICMP header carries the IPv6 address of the second forwarding node. address.

Based on the method provided in the third aspect, in a possible implementation manner, the first control message includes a first IPv6 header, and the first IPv6 header carries the IPv6 address of the second forwarding node.

Based on the method provided in the third aspect, in a possible implementation manner, the second forwarding node determines that it cannot continue to forward the second message currently, including:

When the lifetime TTL of the second message is 1, the second forwarding node determines that it cannot continue to forward the second message.

Based on the method provided in the third aspect, in a possible implementation manner, the second message is a path tracing message.

In a fourth aspect, a network device is provided. The network device includes a memory and a processor; the memory is used to store program instructions; the processor is configured to call the program stored in the memory, so that the network The device performs the method as described in the first aspect.

In a fifth aspect, a network device is provided. The network device includes a memory and a processor; the memory is used to store program instructions; the processor is configured to call the program stored in the memory, so that the network The device performs the method as described in the second aspect.

In a sixth aspect, a network device is provided. The network device includes a memory and a processor; the memory is used to store program instructions; the processor is configured to call the program stored in the memory, so that the network The device performs the method as described in the third aspect.

In the seventh aspect, a network device is provided. The network device includes a transceiver module and a processing module:

The transceiving module is configured to perform transceiver-related operations in the method described in the first aspect, and the processing module is configured to perform operations other than the transceiver-related operations in the method described in the first aspect.

In an eighth aspect, a network device is provided, which includes a transceiver module and a processing module:

The transceiving module is configured to perform transceiver-related operations in the method described in the second aspect, and the processing module is configured to perform operations other than the transceiver-related operations in the method described in the second aspect.

In a ninth aspect, a network device is provided, which includes a transceiver module and a processing module:

The transceiving module is configured to perform transceiver-related operations in the method described in the third aspect, and the processing module is configured to perform operations other than the transceiver-related operations in the method described in the third aspect.

In a tenth aspect, a computer-readable storage medium is provided. Instructions are stored in the computer-readable storage medium. When the instructions are run on a processor, the method described in the first aspect is implemented.

In an eleventh aspect, a computer-readable storage medium is provided. Instructions are stored in the computer-readable storage medium. When the instructions are run on a processor, the method described in the second aspect is implemented.

In a twelfth aspect, a computer-readable storage medium is provided. Instructions are stored in the computer-readable storage medium. When the instructions are run on a processor, the method described in the third aspect is implemented.

In a thirteenth aspect, a computer program product is provided. The computer program product includes instructions that, when run on a processor, implement the method described in the first aspect.

A fourteenth aspect provides a computer program product, which includes instructions that, when run on a processor, implement the method described in the second aspect.

In a fifteenth aspect, a computer program product is provided. The computer program product includes instructions that, when run on a processor, implement the method described in the third aspect.

For the technical effects obtained by the above-mentioned fourth aspect to the fifteenth aspect, reference can be made to the technical effects obtained by the corresponding technical means in the first aspect to the third aspect, and will not be described again here.

Description of drawings

Figure 1 is a schematic diagram of an IPv4 packet traversing an IPv6 network provided by an embodiment of the present application;

Figure 2 is a schematic diagram of a path tracking process provided by an embodiment of the present application;

Figure 3 is a schematic diagram of another path tracking process provided by an embodiment of the present application;

Figure 4 is a schematic architectural diagram of a message forwarding system provided by an embodiment of the present application;

Figure 5 is a schematic architectural diagram of another message forwarding system provided by an embodiment of the present application;

Figure 6 is a flow chart of a message forwarding method provided by an embodiment of the present application;

Figure 7 is a schematic diagram of the format of an ICMP message provided by an embodiment of the present application;

Figure 8 is a schematic diagram of a tracking result provided by an embodiment of the present application;

Figure 9 is a schematic diagram of another path tracking process provided by an embodiment of the present application;

Figure 10 is a schematic structural diagram of a network device provided by an embodiment of the present application;

Figure 11 is a schematic structural diagram of another network device provided by an embodiment of the present application;

Figure 12 is a schematic structural diagram of another network device provided by an embodiment of the present application;

Figure 13 is a schematic architectural diagram of another message forwarding system provided by an embodiment of the present application.

Detailed ways

In order to make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

It should be understood that "plurality" mentioned herein refers to two or more. In the description of this application, unless otherwise stated, "/" means or, for example, A/B can mean A or B; "and/or" in this article is just an association relationship describing related objects, It means that there can be three relationships, for example, A and/or B, which can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in order to facilitate a clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as “first” and “second” are used to distinguish identical or similar items with basically the same functions and effects. Those skilled in the art can understand that words such as "first" and "second" do not limit the number and execution order, and words such as "first" and "second" do not limit the number and execution order.

Before explaining the embodiments of the present application in detail, the application scenarios of the embodiments of the present application are first introduced.

Path tracing (traceroute) technology is a technology used to detect each forwarding node along which a packet forwarding path passes. In path tracing technology, a path detection node can send multiple path tracing messages with the same destination address but different time to live (TTL), for example, 10 different path tracing messages with TTL from 1 to 10. When any forwarding node in the network receives a path tracing message, it will continue to forward the path tracing message after subtracting 1 from the TTL value in the path tracing message. If the TTL of the path tracing message received by the forwarding node is 1, an Internet Control Message Protocol (ICMP) error message is returned to the path detection node. In the ICMP error message Carrying the IP address of the forwarding node. In this way, the path detection node can obtain the IP address of each forwarding node along the packet forwarding path, thereby achieving the purpose of path tracing.

Currently, in the fourth generation network protocol (Internet Protocol version 4, IPv4) network, when the forwarding node determines that the TTL of the message is 1, it returns the IPv4-based network control message protocol (internet control message protocol) to other forwarding nodes. ICMP) error message, the ICMP error message is an IPv4 message, and the ICMP error message carries the IPv4 address of the forwarding node, so that other nodes can learn that there is an error in forwarding the message at the forwarding node.

With the development of network technology, the sixth generation network protocol (Internet Protocol version 6, IPv6) network is gradually replacing the IPv4 network. In this scenario, when IPv4 packets are transmitted in the network, they usually traverse (over) the IPv6 network. This message can be called IPv4 over IPv6 data.

Figure 1 is a schematic diagram of an IPv4 packet traversing an IPv6 network provided by an embodiment of the present application. In Figure 1, CE is used to mark customer edge equipment, PE is used to mark operator edge equipment, and P is used to mark operator intermediate equipment. As shown in Figure 1, CE1 sends an IPv4 packet to CE2. An IPv6 network passes between CE1 and CE2. The packet sent by CE1 enters the IPv6 network on the PE1 node. PE1 encapsulates an additional IPv6 header (abbreviated as IPv6 header in Figure 1) on the outer layer of the packet. IPv6 is forwarded on the intermediate P node of the IPv6 network, and finally reaches the egress node PE2 of the IPv6 network. PE2 will strip off the IPv6 packet header and send the IPv4 packet to CE2.

In the scenario shown in Figure 1, if path tracking is performed, the specific tracking process can be shown in Figure 2. Figure 2 is a schematic diagram of a path tracking process provided by an embodiment of the present application. As shown in Figure 2, the path tracking process includes the following steps.

1. CE1 initiates path tracing (Traceroute) to CE2, that is, it sends multiple path tracing messages with different TTLs.

2. When the TTL in the path tracing message is 1, the path tracing message reaches PE1. PE1 checks the TTL timeout and directly replies to CE1 with a TTL timeout ICMP error message.

3. When the TTL in the path tracing packet is 2, the path tracing packet reaches PE1. PE1 checks the TTL value and determines that forwarding can continue. Then the TTL is decremented by one (the TTL value in the IPv4 header becomes 1), and the IPv6 header is encapsulated in the outer layer of the path tracing message, and the encapsulated path tracing message is forwarded. Among them, the TTL mode of the IPv6 network can be the uniform mode. At this time, the TTL in the encapsulated IPv6 packet header (the TTL field in the actual IPv6 packet header is called Hop limit. In order to unify with IPV4, the Hop limit of IPv6 is also (Uniformly referred to as TTL) is set to be the same as the TTL of the inner IPv4 packet header, that is, the TTL in the IPv6 packet header is also 1. The path tracing message reaches the P node. The P node determines the TTL timeout based on the outer IPv6 message header and needs to reply to CE1 with a TTL timeout ICMP error message.

4. The processing flow when the TTL in the path tracing message is 3 is similar to the processing flow when the TTL is 2, and will not be repeated here.

5. When the TTL in the path tracing packet is 4, the path tracing packet reaches PE1, and PE1 determines that it needs to continue forwarding based on the TTL value. Then reduce the TTL by one (the TTL value in the IPv4 packet header becomes 3), and encapsulate the IPv6 packet header in the outer layer of the path tracing packet. The TTL in the IPv6 packet header is also 3, and the encapsulated route tracing packet is The article continues to be forwarded. The path tracing message reaches the P node. The P node continues to forward the path tracing message based on IPv6, and decrements the TTL of the IPv6 header in the path tracing message by 1 (updates the value to 2), and updates the path tracing message to Forward the document to PE2. After receiving the path tracing packet, PE2 determines that it needs to continue forwarding. At this time, it decrements the IPv6 TTL by 1 and determines that it is the egress node of the IPv6 network, so it needs to strip off the IPv6 packet header. At the same time, because the TTL mode of the IPv6 network where PE2 is located is configured as Uniform mode, PE2 writes the TTL value of the IPv6 header in the path tracing packet to the IPv4 header. TTL, that is, at this time, PE2 strips off the IPv6 header in the received path tracing packet, updates the TTL in the IPv4 packet header to 1, and sends the processed path tracing packet to CE2. After CE2 receives the path tracing message, it determines that the TTL is 1. Since the destination address of the path tracing message is CE2, that is, the path tracing message has reached the destination. At this time, CE2 will perform other processing on the path tracing message. (This application embodiment will not describe this in detail). At the same time, CE2 replies to CE1 with an ICMP error message indicating that the port is unreachable. After CE1 receives the message from CE2, since CE2 is the destination of path tracing, the path tracing process ends. .

The detailed process of the above step 2 can be shown in Figure 3.

In Figure 3, CE1 sends a path tracing message with a TTL of 2 to PE1. The path tracing message includes an IPv4 header and a payload. The IPv4 header carries the source address (SA) 1.1.1.1 and The destination address (DA) is 2.2.2.2, and the TTL in the IPv4 header is 2. After receiving the path tracing message, PE1 reduces the TTL in the IPv4 header of the path tracing message to 1, and encapsulates the IPv6 header in the outer layer (abbreviated as IPv6 header in Figure 3), and the IPv6 message The TTL of the header is also set to 1, and the processed path tracing message continues to be forwarded to the P node. When the P node receives the path tracing message, it determines that the TTL in the IPv6 header has expired, and the P node determines that the received path tracing message includes the IPv4 header, so the P node responds with the ICMP TTL expired message. The error message carries the IPv4 address of the P node 100.1.1.2, and the ICMP error message is sent to CE1 through PE1. As shown in Figure 3, the IPv4 address 100.1.1.2 of the P node is carried in the ICMP header of the ICMP error message (abbreviated as ICMP header in Figure 3).

In the above scenario, if the IPv6 network is an IPv6 private network, when the forwarding node in the IPv6 private network receives a message from a forwarding node in the IPv4 network and determines that the TTL of the message is 1, due to The forwarding node is only configured with an IPv6 address and not an IPv4 address. At this time, the forwarding node in the IPv6 private network has two processing methods. One is: the forwarding node directly discards the message and does not send an IPv4-based ICMP error message to the forwarding node in the IPv4 network. The other is: the forwarding node sends an IPv6-based ICMP error message to the edge node of the IPv6 private network. The IPv6-based ICMP error message carries the IPv6 address of the forwarding node, and the edge node receives the IPv6-based ICMP error message. When the error message is sent, the error message needs to be forwarded to the forwarding node in the IPv4 network. However, since the edge node receives an IPv6-based ICMP error message and the network that needs to be advertised is an IPv4 network, the edge node will also discard the IPv6-based ICMP error message at this time. Both of these processing methods will cause the forwarding node in the IPv4 network to be unable to detect errors in forwarding the packet in the IPv6 private network.

Based on this, embodiments of this application provide a message forwarding method. On the one hand, this method can realize the forwarding node in the IPv6 private network to notify the node in the IPv4 network of the packet forwarding situation. On the other hand, if the forwarding node in the IPv6 network is configured with an IPv4 address, but the forwarding node is unwilling to expose the IPv4 address to the network, this method can also be used to advertise packets to nodes in the IPv4 network. Forwarding status.

The message forwarding system, message forwarding method and related devices provided by the embodiments of the present application are explained in detail below.

Figure 4 is a schematic architectural diagram of a message forwarding system provided by an embodiment of the present application. As shown in Figure 4, the message forwarding system includes a first forwarding node 401, a second forwarding node 402 and a third forwarding node 403. The first forwarding node 401 communicates with the second forwarding node 402, and the second forwarding node 402 communicates with the third forwarding node 403.

Among them, the first forwarding node 401 is an edge node of the IPv6 network, the second forwarding node 402 is located in the IPv6 network, and the third forwarding node 403 is located in the IPv4 network. The second forwarding node 402 located in the IPv6 network can be understood as: second forwarding Node 402 is an intermediate node of the IPv6 network. That is, the forwarding nodes in the IPv6 network include edge nodes and intermediate nodes. The edge nodes are used to communicate with forwarding nodes in other networks, and the intermediate nodes only communicate with forwarding nodes in the same network. It can also be understood that the third forwarding node 403 is located in the IPv4 network: the third forwarding node 403 is an intermediate node of the IPv4 network.

In this embodiment of the present application, the IPv6 network may be an IPv6 dedicated network. The intermediate nodes in the IPv6 private network only have IPv6 addresses and do not have IPv4 addresses. Edge nodes in IPv6 private networks have both IPv4 addresses and IPv6 addresses.

Among them, the intermediate node does not have an IPv4 address may mean that when the IP address is allocated, the IPv4 address is not configured for the intermediate node. In this case, the intermediate node naturally does not have an IPv4 address. In other words, for the intermediate node in the IPv6 private network, the IPv4 address is not configured for the intermediate node.

It should be noted that in the embodiment of the present application, the forwarding node does not have an IPv4 address. In addition to the above-mentioned intermediate node in the IPv6 dedicated network, it may also include another situation. This situation is: the forwarding node is configured with an IPv4 address, but the IPv4 address is not used externally in some scenarios, that is, the IPv4 address is not exposed on the network.

It should be noted that the nodes in the message forwarding system shown in Figure 4 are used for illustration. The message forwarding system may also include other nodes, and examples will not be given one by one here.

Figure 5 is a schematic architectural diagram of another message forwarding system provided by an embodiment of the present application. As shown in Figure 5, the message forwarding system includes five forwarding nodes, which are marked CE1, PE1, P, PE2, and CE2 in Figure 5.

Among them, CE1 and CE2 are located in the IPv4 network, PE1 and PE2 are edge nodes of the IPv6 private network, and P is the intermediate node of the IPv6 private network. Based on this, CE1 communicates with PE1, PE1 and PE2 communicate with P respectively, and PE2 communicates with CE2.

In this scenario, the first forwarding node 401 in Figure 4 can be PE1 in Figure 5 , the second forwarding node 402 can be P in Figure 5 , and the third forwarding node 403 can be CE1 in Figure 5 . Optionally, the first forwarding node 401 in Figure 4 may be PE2 in Figure 5, the second forwarding node 402 may be P in Figure 5, and the third forwarding node 403 may be CE2 in Figure 5.

It should be noted that the forwarding node involved in the embodiment of this application may be a network element with network layer functions, such as a router, a layer 3 switch, etc. No more examples will be given here.

Figure 6 is a flow chart of a message forwarding method provided by an embodiment of the present application. As shown in Figure 6, the message forwarding method includes the following steps.

Step 601: The third forwarding node sends a first message to the first forwarding node, and the first message is an IPv4 message. Among them, the third forwarding node is located in the IPv4 network, and the first forwarding node is an edge node of the IPv6 network.

The first message may be a service message in the service flow, or may be a path tracing message in a path tracing scenario.

The first message is an IPv4 message, which can be understood as: the first message includes an IPv4 header and a payload. The IPv4 header carries the source address and destination address corresponding to the payload. The source address and destination address are both IPv4 addresses. Based on this, the first message is a message that needs to be sent to the IPv4 network. Among them, the source address corresponding to the payload can be understood as the address of the communication end that generates the data corresponding to the payload. The destination address corresponding to the payload can be understood as the address of the destination communication end to which the payload needs to be sent.

In addition, since the first forwarding node is an edge node of the IPv6 network, the first packet is a packet that needs to be sent to the IPv4 network across the IPv6 network.

For example, in the packet forwarding system shown in Figure 5, the third forwarding node is CE1 and the first forwarding node is PE1. The first message is a message sent by CE1 to CE2. The source address corresponding to the payload in the first message is the IPv4 address of CE1, and the destination address corresponding to the payload is the IPv4 address corresponding to CE2. This message needs to be sent to CE2 through PE1, so when CE1 determines the first message, CE1 sends the first message to PE1.

Step 602: The first forwarding node receives the first message, generates a second message based on the first message, and sends the second message to the second forwarding node. The second message is an IPv6 message. Wherein, the second forwarding node is located in the IPv6 network.

Since the first message is an IPv4 message, and the first forwarding node is an edge node of the IPv6 network, when receiving the first message, the first forwarding node needs to send the first message to the third node in the IPv6 network. Two forwarding nodes, to send the first message to the destination in the IPv4 network through the second forwarding node.

In some embodiments, the first packet may only include an IPv4 packet header and a payload. In this case, the source address and destination address carried by the IPv4 packet header are the source address and destination address corresponding to the payload respectively. In this scenario, the implementation process of the first forwarding node generating the second message based on the first message may be: the first forwarding node encapsulates the IPv6 header in the outer layer of the first message to obtain the second message. The source address carried in the IPv6 packet header is the IPv6 address of the first forwarding node, and the destination address carried in the IPv6 packet header is the IPv6 address of another forwarding node in the IPv6 network. The first forwarding node searches the forwarding table based on the destination address in the IPv6 message header to obtain the outbound interface (that is, the next hop interface) for forwarding the second message. The next hop interface is between the first forwarding node and the second forwarding node. An interface for communication, and then the first forwarding node sends the second message through the found next hop interface, so as to send the second message to the second forwarding node.

For example, in the packet forwarding system shown in Figure 5, the third forwarding node is CE1 and the first forwarding node is PE1. The first message is a message sent by CE1 to CE2. When PE1 receives the first message, the source address of the IPv6 header in the second message generated based on the first message is the IPv6 address of PE1, and the destination address is the IPv6 address of PE2. The first forwarding node searches the forwarding table based on the IPv6 address of PE2 in the IPv6 packet header to obtain the next hop interface. The next hop interface is the interface on PE1 that communicates with P. Then PE1 passes the second packet through the found The next hop interface is used to send the second message to P, and then to PE2 through P.

In other embodiments, the first message may include an outer IPv4 message header, an inner IPv4 message header and a payload. The source address and destination address carried by the inner IPv4 message header are respectively corresponding to the payload. Source address and destination address. The source address and destination address carried in the outer IPv4 packet header are respectively the addresses of other nodes on the packet forwarding path. For example, in the scenario shown in Figure 5, if a VPN network is deployed between CE1 and PE1, the source address and destination address carried in the outer IPv4 packet header can be the source address and destination address of the VPN tunnel in the VPN network. Destination address. In this scenario, the implementation process for the first forwarding node to generate the second message based on the first message can be as follows: the first forwarding node peels off the outer IPv4 header of the first message, and then sends the inner IPv4 message The outer layer of the header and payload encapsulates the IPv6 message header to obtain the second message. For explanations about the source address and destination address carried in the IPv6 packet header, please refer to the previous paragraph and will not be repeated here.

Based on the above two embodiments, the second message is generated based on the first message. It can be understood that the second message includes the payload in the first message and the IPv4 header carrying the source address and destination address corresponding to the payload.

Step 603: The second forwarding node receives the second message, and generates the first control based on the second message after determining that it cannot continue to forward the second message and the second message has an IPv4 message header. message, and sends a first control message to the first forwarding node, where the first control message is an IPv6 message, and the first control message is used to notify the second forwarding node of forwarding the second message.

When the second forwarding node determines that it cannot continue to forward the second message, in order to facilitate the sender of the second message (that is, the first forwarding node) to learn the situation in a timely manner, the second forwarding node may generate a notification for the second message. The message forwarding situation is a control message, and sends the first control message to the sender of the second message.

In some embodiments, the implementation process by which the second forwarding node determines that it cannot continue to forward the second message may be: when the TTL of the second message is 1, the second forwarding node determines that it cannot continue to forward the second message. . For example, in the current path tracing (traceroute) scenario, the first message and the second message are both path tracing messages.

Optionally, the second forwarding node may also determine that it cannot continue to forward the second message in other scenarios. For example, if the data size of the second message exceeds the forwarding capability of the second forwarding node, the second forwarding node may also generate a first control message to notify the second forwarding node of forwarding the second message. The embodiments of this application will not give examples one by one for various scenarios in which the second forwarding node is currently unable to continue forwarding the second message.

In addition, in some embodiments, the implementation process of the second forwarding node generating the first control message based on the second message may be: the second forwarding node uses all or part of the second message as the first control message to be generated. payload, and then generates a first control message based on the determined payload. In this way, when the first forwarding node subsequently receives the first control message, it parses the payload of the first control message and determines that the first control message is a control message for the second message, that is, it learns the first control message. The message is used to notify the forwarding status of the second message.

Optionally, the second forwarding node may also generate the first control message based on the second message through other methods. The embodiments of this application will not be explained one by one here.

In addition, in this embodiment of the present application, the second forwarding node may generate a first control message through Internet Control Message Protocol (ICMP) to notify the second forwarding node of the packet forwarding status through ICMP. In this case, the first control message is an ICMP message, which may be an ICMP error message, for example. The format of the ICMP message will be explained in detail later, so we will not go into it here.

Optionally, the second forwarding node may also generate the first control message through other protocols to notify the second forwarding node of the packet forwarding status. The embodiments of the present application will not be described one by one here.

The first control message will be explained in detail below.

(1) The first control message carries the IPv6 dedicated network identifier.

Based on the network architecture shown in Figure 4, it can be seen that if the IPv6 network where the second forwarding node is located is an IPv6 dedicated network, no IPv4 address is configured on the second forwarding node. In this scenario, in order to trigger the first forwarding node to use the method provided by the embodiment of the present application to notify the third forwarding node of the second forwarding node forwarding the second message, the second forwarding node can carry IPv6 in the first control message. The IPv6 dedicated network identifier of the network, so that the first forwarding node determines that the second forwarding node does not have an IPv4 address based on the IPv6 dedicated network identifier, and then uses the method provided by the embodiment of the present application to notify the third forwarding node of forwarding by the second forwarding node. The situation of the second message.

The IPv6 dedicated network identifier is used to identify the IPv6 network where the second forwarding node is located as an IPv6 dedicated network. That is, the IPv6 dedicated network identifier is used to indicate that the intermediate node in the IPv6 network where the second forwarding node is located is not configured with an IPv4 address.

The following takes the first control message as an ICMP message as an example to illustrate how the first control message carries the IPv6 dedicated network identifier.

In order to facilitate understanding, the basic format of ICMP messages is explained here. Figure 7 is a schematic diagram of the format of an ICMP message provided by an embodiment of the present application. As shown in Figure 7, the ICMP message usually includes an IP header (abbreviated as IP header in Figure 7), an ICMP message header (abbreviated as ICMP header in Figure 7) and ICMP data.

Among them, the IP header is an IPv4 header or an IPv6 header, and the IPv4 header or IPv6 header carries the destination address and source address to guide the forwarding of ICMP messages. The ICMP header includes the checksum of the entire ICMP data. Optionally, the ICMP message header may also include a checksum of the source address, destination address, and next message header fields in the IP message header. In addition, the packet content field in the ICMP message header usually also includes the source address and destination address. The source address in the ICMP message header is the address of the node that generated the ICMP message, and the destination address in the ICMP message header is The address of the node that needs to be advertised in the ICMP message. ICMP data is used to carry the payload of ICMP messages.

Optionally, in request for comments (RFC) 4884, as shown in Figure 7, an extension data structure (extension data structure) can also be added at the end of the ICMP data. The extended data structure includes an extended message header (abbreviated as extension header in Figure 7) and a variable number of extended objects to extend the functions of the ICMP message.

Based on the basic format of the above ICMP message, in some embodiments, the first control message is an ICMP message, and the first control message includes a first extension object, and the first extension object carries an IPv6 dedicated network identifier.

That is, when the first control message is a Network Control Message Protocol ICMP message, the IPv6 dedicated network identifier can be carried by the first extension object added at the end of the payload of the ICMP message.

By way of example, FIG. 7 also shows a schematic format diagram of an extension object provided by an embodiment of the present application. As shown in Figure 7, the extended object includes a length field, an object identification field, an object type field, an incoming interface index field, an incoming interface address field, etc. At this time, the object identification field in the first extension object can be used to carry the IPv6 dedicated network identification.

Optionally, the IPv6 dedicated network identifier can also be carried through other fields in the first extension object, which will not be explained one by one here. For relevant descriptions of each field in the first extension object, please refer to RFC4884.

In some other embodiments, the first control message is a Network Control Message Protocol ICMP message, and the first control message includes a first ICMP header, and the first ICMP header carries an IPv6 dedicated network identifier.

That is, when the first control message is a Network Control Message Protocol ICMP message, the IPv6 dedicated network identifier may not be carried in the first extension object added at the end of the payload of the ICMP message, but instead the field in the ICMP message header may be Extended to carry IPv6 private network identities.

For example, based on the format of the ICMP message header shown in Figure 7, the type field or code field in the first ICMP message header can be extended so that the type field or code field can carry the IPv6 dedicated network identifier.

Optionally, the IPv6 dedicated network identifier can also be carried through other fields in the first ICMP message header, which will not be explained one by one here.

(2) The first control message carries the IPv6 address of the second forwarding node.

In order to be able to notify the first forwarding node that the second forwarding node is currently unable to continue forwarding the second message, in the embodiment of the present application, when generating the first control message, the second forwarding node may also carry The IPv6 address of the second forwarding node.

In some embodiments, the first control message is an ICMP message, and the first control message includes a second extension object, and the second extension object carries the IPv6 address of the second forwarding node.

That is, when the first control message is a Network Control Message Protocol ICMP message, the IPv6 address of the second forwarding node can be carried through a second extension object added at the end of the payload of the ICMP message.

For example, if the format of the second extension object is as shown in Figure 7, the IPv6 address of the second forwarding node can be carried through the incoming interface address field in the second extension object.

Optionally, the IPv6 address of the second forwarding node can also be carried through other fields in the second extension object, which will not be explained one by one here.

The second extension object and the aforementioned first extension object may be the same extension object, or they may be different extension objects. The embodiments of the present application are not limited to this.

In other embodiments, the first control message is an ICMP message, and the first control message includes a second ICMP message header, the second ICMP message header carries the IPv6 address of the second forwarding node;

That is, when the first control message is a Network Control Message Protocol ICMP message, the second extension object may not be added at the end of the payload of the ICMP message to carry the IPv6 address of the second forwarding node, but the IPv6 address of the second forwarding node may be carried in the header of the ICMP message. The fields in are extended to carry the IPv6 address of the second forwarding node.

For example, based on the format of the ICMP message header shown in Figure 7, the packet content field in the first ICMP message header can be extended so that the field can carry the IPv6 address of the second forwarding node.

Optionally, the IPv6 address of the second forwarding node may also be carried through other fields in the second ICMP message header, which will not be explained one by one here.

In addition, from the format of the ICMP message shown in Figure 3, when the first control message is an ICMP message, the first control message includes the first IPv6 header, and the source address carried in the first IPv6 header is the IPv6 address of the second forwarding node. Based on this, in other embodiments, the ICMP message may not be extended. In this case, when the second forwarding node determines that it cannot continue to forward the second message, it may generate the third ICMP message without extending the message. A control message.

It should be noted that the various options in which the first control message carries the IPv6 dedicated network identifier can be used in combination with the various options in which the first control message carries the IPv6 address of the second forwarding node. For example, the first control message includes the extended object shown in Figure 7, the IPv6 dedicated network identifier is carried through the object identification field in the extended object, and the IPv6 address of the second forwarding node is carried through the incoming interface address field in the extended object. Other combination schemes will not be explained one by one here.

In addition, the first control message may not carry the IPv6 dedicated network identifier, but may only carry the IPv6 address of the second forwarding node through any of the above solutions. Here again no examples will be given one by one.

Step 604: The first forwarding node receives the first control message. When the first forwarding node determines that the second forwarding node does not have an IPv4 address, it generates a second control message based on the first control message and sends the second control message to the third forwarding node. message, the second control message is an IPv4 message, and the second control message carries the IPv6 address of the second forwarding node.

Since the first control message is used to notify the second forwarding node of forwarding the second message, and the second message is generated based on the first message, when receiving the first control message, the first forwarding node needs to The third forwarding node, the sender of the first message, announces the forwarding status of the message. Based on this, when receiving the first control message, the first forwarding node generates a second control message based on the first control message to send the second control message to the third forwarding node. And in order to notify the third forwarding node that the second forwarding node forwards the message, the second control message needs to carry the IPv6 address of the second forwarding node.

In addition, since the third forwarding node is a node in the IPv4 network, the second control message needs to be an IPv4 message, so that the second control message can be sent to the third forwarding node. Therefore, the embodiment of the present application provides a solution that can carry the IPv6 address of the second forwarding node in the second control message in the IPv4 message format, so as to realize the notification of the IPv6 address to the third forwarding node in the opposite IPv4 network. The second forwarding node forwards the message.

In addition, it should be noted that since some nodes in the IPv6 network may also be configured with IPv4 addresses, in this scenario, there is no need to generate the second control message through the method provided by the embodiments of this application. Therefore, after the first forwarding node receives the first control message, the first forwarding node first determines whether the second forwarding node has an IPv4 address. If it has an IPv4 address, it can directly notify the third forwarding node based on the IPv4 address. When the first forwarding node determines that the second forwarding node does not have an IPv4 address, the first forwarding node generates a second control message based on the first control message through the method provided in the embodiment of the present application, so as to implement the second control message in the IPv4 message format. The control message carries the IPv6 address of the second forwarding node.

In some embodiments, in the scenario where the first control message carries an IPv6 dedicated network identifier, since the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network where the second forwarding node is located does not have an IPv4 address configured, that is, the second forwarding node The IPv6 network where the forwarding node is located is an IPv6 dedicated network, so the first forwarding node can determine that the second forwarding node does not have an IPv4 address through the IPv6 dedicated network identifier.

Based on this, the implementation process of the first forwarding node determining that the second forwarding node does not have an IPv4 address may be: the first forwarding node parses the first control message to obtain the IPv6 dedicated network identifier; the first forwarding node determines the second forwarding node based on the IPv6 dedicated network identifier. The second forwarding node does not have an IPv4 address.

The detailed implementation method of the first forwarding node parsing the first control message to obtain the IPv6 dedicated network identifier is related to how the first control message carries the IPv6 dedicated network identifier. Here, the following two scenarios are used as examples. The parsing process in other scenarios can also refer to the following examples, and will not be explained one by one.

For example, in a scenario where the first control message is an ICMP message, and the first control message includes a first extension object, and the first extension object carries an IPv6 dedicated network identifier, the first forwarding node can obtain the IPv6 by parsing the first extension object. Private network identifier.

As another example, in a scenario where the first control message is an ICMP message, and the first control message includes a first ICMP header, and the first ICMP header carries an IPv6 dedicated network identifier, the first forwarding node may parse the first An ICMP header obtains the IPv6 private network identification.

In other embodiments, the network administrator may configure the first forwarding node in advance with an IPv6 dedicated network identifier corresponding to the IPv6 network where the second forwarding node is located. In this scenario, the implementation process for the first forwarding node to determine that the second forwarding node does not have an IPv4 address may be: the first forwarding node obtains a locally stored IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates the IPv6 address where the second forwarding node is located. The intermediate node in the network is not configured with an IPv4 address, so the first forwarding node can determine that the second forwarding node does not have an IPv4 address based on the IPv6 dedicated network identifier.

The implementation method for the first forwarding node to obtain the locally stored IPv6 dedicated network identifier may be: the first forwarding node determines the network prefix of the IPv6 network where the second forwarding node is located based on the first control message, and then obtains the network prefix corresponding to the IPv6 network identifier from the local storage. The IPv6 dedicated network identifier corresponding to the network prefix.

For example, the implementation process of the first forwarding node determining the network prefix of the IPv6 network where the second forwarding node is located based on the first control message may be: the first forwarding node parses the source address in the IPv6 header of the first control message. , the source address is the IPv6 address of the second forwarding node, and the first forwarding node can determine the network prefix of the IPv6 network based on the IPv6 address of the second forwarding node.

The network prefix is a network number that uniquely identifies a network. Therefore, when the network administrator configures the IPv6 dedicated network identifier corresponding to the IPv6 network where the second forwarding node is located on the first forwarding node, the network prefix of the IPv6 network and the IPv6 Correspondence between dedicated network identifiers, so that the first forwarding node can subsequently find the IPv6 dedicated network identifier based on the network prefix index.

Optionally, in some scenarios, the second forwarding node is configured with an IPv4 address, but when generating the first control message, the second forwarding node is unwilling to expose the IPv4 address to the network for some reasons. In this case The first control message does not carry the IPv4 address of the second forwarding node. In this scenario, when the first forwarding node receives the first control message, the first control message does not carry the IPv6 dedicated network identifier, and the first forwarding node does not obtain the IPv6 dedicated network identifier from local storage. At this time The first forwarding node may also determine that the second forwarding node does not have an IPv4 address.

Therefore, in this embodiment of the present application, the first forwarding node determines that the second forwarding node that does not have an IPv4 address satisfies one of the following two conditions. One is that the intermediate node in the IPv6 network where the second forwarding node is located is not configured with an IPv4 address. The other is that the second forwarding node is configured with an IPv4 address, but the IPv4 address of the second forwarding node is not used externally.

In addition, in this embodiment of the present application, in order to notify the third forwarding node that the second forwarding node forwards the packet, the second control message needs to carry the IPv6 address of the second forwarding node. Based on this, before generating the second control message, the first forwarding node needs to obtain the IPv6 address of the second forwarding node.

The process of how the first forwarding node obtains the IPv6 address of the second forwarding node and generates the second control message is described in detail below.

In some embodiments, in a scenario where the first control message carries the IPv6 address of the second forwarding node, the implementation process of the first forwarding node generating the second control message based on the first control message may be: the first forwarding node generates the second control message from the first forwarding node. Obtain the IPv6 address of the second forwarding node from the control message to generate the second control message.

The implementation manner in which the first forwarding node obtains the IPv6 address of the second forwarding node from the first control message is related to the manner in which the first control message carries the IPv6 address of the second forwarding node. Here, the following three scenarios are used as examples. The acquisition process in other scenarios can also refer to the following examples, and will not be explained one by one.

For example, in a scenario where the first control message is an ICMP message, and the first control message includes a second extension object, and the second extension object carries the IPv6 address of the second forwarding node, the first forwarding node obtains the IPv6 address from the first control message. The implementation process of obtaining the IPv6 address of the second forwarding node may be: the first forwarding node obtains the IPv6 address of the second forwarding node from the second extension object.

For example, when the second extension object includes the incoming interface address field, the first forwarding node can obtain the IPv6 address of the second forwarding node from the incoming interface address field of the second extension object.

As another example, in a scenario where the first control message is an ICMP message, and the first control message includes a second ICMP header, and the second ICMP header carries the IPv6 address of the second forwarding node, the first forwarding node The implementation method of obtaining the IPv6 address of the second forwarding node in the first control message may be: the first forwarding node obtains the IPv6 address of the second forwarding node from the second ICMP message header.

For example, when the second ICMP message header includes a packet content field, the first forwarding node may obtain the IPv6 address of the second forwarding node from the packet content field of the second ICMP message header.

As another example, in a scenario where the first control message includes a first IPv6 header and the first IPv6 header carries the IPv6 address of the second forwarding node, the first forwarding node obtains the second forwarding node from the first control message. The IPv6 address is implemented as follows: the first forwarding node obtains the IPv6 address of the second forwarding node from the first IPv6 message header.

Wherein, the source address of the first IPv6 message header is the IPv6 address of the second forwarding node.

In other embodiments, the network administrator may configure the IPv6 address of the second forwarding node on the first forwarding node in advance, that is, the first forwarding node locally stores the IPv6 address of the second forwarding node. In this scenario, the implementation process of the first forwarding node generating the second control message based on the first control message is: the first forwarding node obtains the locally stored IPv6 address of the second forwarding node to generate the second control message based on the first control message and the second forwarding node. The IPv6 address generates a second control message.

When the network administrator configures the IPv6 address of the second forwarding node on the first forwarding node, the network administrator can establish a corresponding relationship between the IPv6 address of the second forwarding node and the incoming interface. interface, the IPv6 address of the second forwarding node can be indexed from local storage. Optionally, the first forwarding node may also obtain the stored IPv6 address of the second forwarding node through other methods, which is not limited in this embodiment of the present application.

In addition, in this embodiment of the present application, in order to notify the third forwarding node that the second forwarding node forwards the packet, the second control message needs to carry the IPv6 address of the second forwarding node. The following implementation methods may be used to carry the IPv6 address of the second forwarding node in the second control message.

In some embodiments, the second control message is an ICMP message, and the second control message includes a third extension object, and the third extension object carries the IPv6 address of the second forwarding node.

In some other embodiments, the second control message is a Network Control Message Protocol ICMP message, and the first control message includes a third ICMP header, and the third ICMP header carries the IPv6 address of the second forwarding node.

For the specific implementation method of carrying the IPv6 address of the first forwarding node in the second control message, please refer to the implementation method of carrying the IPv6 address of the second forwarding node in the first control message through an extension object or ICMP message header, which will not be described again here. .

It should be noted that, since the first control message includes the first IPv6 packet header, the first control message may also carry the IPv6 address of the second forwarding node in the first IPv6 packet header. However, the second control message is an IPv4 message, so the second control message does not include an IPv6 header. Therefore, the second control message needs to carry the IPv6 of the second forwarding node through an extended object or an extended ICMP header or other extension methods. address.

In addition, in this embodiment of the present application, if the IPv6 network where the second forwarding node is located is an IPv6 dedicated network, the second control message may also carry an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates the IPv6 network where the second forwarding node is located. The intermediate nodes in are not configured with IPv4 addresses. Among them, the second forwarding node can carry the IPv6 dedicated network identifier in the following ways.

In some embodiments, the second control message is an ICMP message, and the second control message includes a fourth extension object, and the fourth extension object carries the IPv6 dedicated network identifier.

In some other embodiments, the second control message is an ICMP message, and the second control message includes a fourth ICMP header, and the fourth ICMP header carries the IPv6 dedicated network identifier.

For a specific implementation method of carrying the IPv6 dedicated network identifier in the second control message, please refer to the implementation method of carrying the IPv6 dedicated network identifier in the first control message through an extension object or an ICMP message header, which will not be described again here.

The above description takes the second control message as an ICMP message as an example to illustrate how the second control message carries the IPv6 address and IPv6 dedicated network identifier of the second forwarding node. Optionally, when the second control message is implemented through other protocols, the second control message under other protocols can also be extended so that the second control message carries the IPv6 address and IPv6 dedicated network identifier of the second forwarding node. This is also not explained in detail.

Step 605: The third forwarding node receives the second control message, and determines whether the second forwarding node forwards the first message based on the second control message.

After the third forwarding node sends the first message to the first forwarding node, based on the aforementioned steps 602 to 604, the third forwarding node will receive the second control message sent by the first forwarding node. Based on step 604, it can be seen that the second control message is an IPv4 message and the second control message carries the IPv6 address of the second forwarding node.

Since the second control message carries the IPv6 address of the second forwarding node, when the third forwarding node receives the second control message sent by the first forwarding node, it can know that it is the second forwarding node based on the IPv6 address of the second forwarding node. The first forwarding node is triggered to send the second control message to notify the second forwarding node of forwarding the first message through the first forwarding node.

For example, the second control message indicates that when the first packet reaches the second forwarding node, the TTL of the first packet expires. That is, the second control message is used to notify the second forwarding node that there is an error in forwarding the first message, and the cause of the error is that the TTL of the first message has expired.

For example, in the path tracing scenario, the first message is a path tracing message. After the third forwarding node sends a path tracing message to the first forwarding node, when the third forwarding node receives the second control message, it will 2. Control messages carried The IPv6 address of the second forwarding node can determine that the TTL in the path tracing message is 1 when the path tracing message is transmitted to the second forwarding node, so the second forwarding node cannot continue to forward the path tracing message. That is, based on the IPv6 address of the second forwarding node carried in the second control message, it can be determined that the second forwarding node cannot continue to forward the first message.

In addition, after the third forwarding node determines the situation of the second forwarding node forwarding the first message based on the second control message in order to facilitate the network administrator to timely understand the situation of the second forwarding node forwarding the first message, the third forwarding node also The second control message can be further parsed to obtain the IPv6 address of the second forwarding node; and then the third forwarding node displays the IPv6 address of the second forwarding node.

For example, in a path tracing scenario, when displaying the IPv6 address of the second forwarding node, the third forwarding node may also display the value of the initial TTL of the first packet sent by the third forwarding node. This allows the network administrator to determine the node traced by the path tracing packet with this TTL value.

For example, assuming that the third forwarding node is CE1 in the architecture shown in Figure 5, the first forwarding node is PE1, and the second forwarding node is P, then CE1 can display the tracking results shown in Figure 8 in the path tracing scenario.

As shown in Figure 8, the destination address of path tracing is the IPv4 address 2.2.2.2 of CE2 (shown as tracert 2.2.2.2 in Figure 8). That is, the destination address of the payload in all first messages (ie, path tracing messages) initiated by CE1 is 2.2.2.2.

When the TTL in the first packet is 1, the tracked node is PE1, so the IPv4 address of PE1 is 100.1.1.1. The three 1 milliseconds (ms) in the second line in Figure 8 indicate that CE1 sent three first messages with a TTL of 1 respectively. Each 1ms indicates the time between sending the corresponding first message and receiving the second control message. of duration.

When the TTL in the first packet is 2, the tracked node is P, so P's IPv6 address A2::2 is displayed. The three 1 milliseconds (ms) in the third row in Figure 8 also indicate that CE1 sent three first messages with a TTL of 2 respectively. It should be noted that the IPv6 network where P is located in Figure 5 is an SRv6 network, so the IPv6 address of P is the segment identity (SID) assigned to it by the SRv6 network, and the SID is A2::2.

The specific implementation manner in which the third forwarding node parses the second control message to obtain the IPv6 address of the second forwarding node is related to the manner in which the second control message carries the IPv6 address of the second forwarding node. For details, please refer to the relevant content of the second control message in step 604, which will not be described again here.

It should be noted that since the IPv6 address of the second forwarding node has 128 bits, and in some scenarios the third forwarding node may not have the ability to display a 128-bit IPv6 address, in this case the third forwarding node may display a prompt. Information, this prompt information is used when the currently tracked second forwarding node is a node in the IPv6 network.

In addition, when the second forwarding node is an intermediate node in the IPv6 dedicated network, in order to facilitate the network administrator to know the IPv6 network where the second forwarding node is located in a timely manner, the third forwarding node determines the forwarding by the first forwarding node based on the second control message. After the first message is received, the third forwarding node can further determine the IPv6 dedicated network identifier of the IPv6 network. The IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network where the second forwarding node is located configures an IPv4 address; then the third forwarding node The node displays the IPv6 private network identification.

In some embodiments, the implementation process of the third forwarding node determining the IPv6 dedicated network identifier of the IPv6 network may be: the third forwarding node parses the second control message to obtain the IPv6 dedicated network identifier. That is, the third forwarding node obtains the IPv6 dedicated network identifier from the second control message.

The specific implementation manner in which the third forwarding node parses the second control message to obtain the IPv6 dedicated network identifier is related to the manner in which the second control message carries the IPv6 dedicated network identifier. For details, please refer to the relevant content of the second control message in step 604, which will not be described again here.

Optionally, in other embodiments, the third forwarding node may also obtain the IPv6 dedicated network identifier from local storage. For a specific implementation method, reference can be made to the process of the first forwarding node obtaining the IPv6 dedicated network identifier from local storage, which will not be described again here.

In summary, based on the embodiment shown in Figure 6, when the first forwarding node of the edge node of the IPv6 network receives the first control message from the second forwarding node in the same IPv6 network, since the first control message is used to notify the third The second forwarding node forwards the second message, and the second message is generated based on the first message from the IPv4 network. Therefore, when receiving the first control message, the first forwarding node needs to send a message to the first message. The sender (the third forwarding node in the IPv4 network) announces the forwarding status of the packet. Based on this, when the first forwarding node receives the first control message, the first forwarding node generates a second control message based on the first control message, and the second control message is an IPv4 message to forward to the third party in the IPv4 network. The node sends a second control message. And when the second forwarding node does not have an IPv4 address, in order to successfully notify the third forwarding node in the IPv4 network that the second forwarding node in the IPv6 network forwards the message, the embodiment of the present application extends the second control message. , to carry the IPv6 address of the second forwarding node in the second control message. Therefore, through the method provided by the embodiments of this application, the intermediate node in the IPv6 network can successfully notify the forwarding node in the IPv4 network of the packet forwarding status when it does not have an IPv4 address.

It should be noted that various optional solutions in steps 601 to 605 in the embodiment shown in FIG. 6 can be combined based on requirements, and this embodiment of the present application will not illustrate this one by one.

The following uses the path tracking flow chart shown in FIG. 9 as an example to further explain the embodiment of the present application. Among them, FIG. 9 is an example solution of various optional solutions in FIG. 6 and does not constitute a limitation to the solution provided by the embodiment of the present application.

As shown in Figure 9. The path tracing process includes the following steps.

(1) CE1 sends a path tracing message with a TTL of 2 to PE1. The path tracing message includes an IPv4 header and a payload. The IPv4 header carries the source address (SA) 1.1.1.1 and the destination address (DA). 2.2.2.2, and the TTL in the IPv4 header is 2.

(2) After receiving the path tracing message, PE1 reduces the TTL in the IPv4 header of the path tracing message to 1, and encapsulates the IPv6 header in the outer layer (abbreviated as IPv6 header in Figure 9), and The TTL (actually Hop) of the IPv6 packet header is also set to 1, and the processed path tracing packet continues to be forwarded to P.

(3) When P receives the path tracing message, it determines that the TTL in the IPv6 header of the path tracing message has expired, and P determines that the received path tracing message includes an IPv4 header, so P based on this The solution provided by the application embodiment generates an ICMP error message (that is, the first control message) that needs to notify the TTL timeout.

As shown in Figure 9, the ICMP error message generated by P directly uses the received path tracing message as ICMP data (that is, the payload of the ICMP error message), and then adds an extension object at the end of the ICMP data and adds the The outer layer of the data is obtained by sequentially adding an ICMP header (abbreviated as ICMP header in Figure 9) and an IPv6 message header (abbreviated as IPv6 header in Figure 9). Among them, the extension object carries the IPv6 dedicated network identifier and the IPv6 address of P. It should be noted that the IPv6 network where P is located in Figure 9 is an SRv6 network, so the IPv6 address of P is the segment identity (SID) assigned to it by the SRv6 network, and the SID is A2::2.

In addition, it should be noted that the ICMP header in the ICMP error message generated by P can be used to indicate that the current IPv6 network forwarding error occurs. For the specific indication method, please refer to the relevant protocol, which will not be described in detail here. Therefore, the ICMP header in the ICMP error message generated by P can also be called an ICMPv6 header.

(4) When PE1 receives the ICMP error message sent by P, it peels off the outer IPv6 header of the ICMP error message and the IPv6 header in the ICMP data, and then removes the remaining IPv4 header and payload. As new ICMP data, the ICMP error message (that is, the second control message) is reconstructed based on the new ICMP data and extended object, and will be re-constructed. The constructed ICMP error message is sent to CE1.

It should also be noted that since the reconstructed ICMP error message needs to be sent to the IPv4 network, the ICMP header in the reconstructed ICMP error message can be used to indicate IPv4 network errors. For specific instructions, please refer to the relevant The agreement will not be described in detail here. Therefore, the ICMP header in the ICMP error message reconstructed by PE1 can also be called an ICMPv4 header.

(5) When CE1 receives the ICMP error message reconstructed by PE1, it obtains the IPv6 address of the P node based on the extended object in the received ICMP error message, thereby tracking the IPv6 address of the P node when the TTL is 2.

Figure 10 is a schematic structural diagram of a network device provided by an embodiment of the present application. The network device is any forwarding node in the message forwarding system shown in Figure 4, such as the first forwarding node or the second forwarding node or the third forwarding node. forwarding node.

Specifically, as shown in Figure 10, the network device 1000 includes a transceiver module 1001 and a processing module 1002.

Among them, the transceiver module 1002 is used to perform transceiver-related operations in the embodiment of FIG. 6; the processing module 1001 is used to perform operations other than transceiver-related operations in the embodiment of FIG. 6.

In the scenario where the network device 1000 shown in Figure 10 is the first forwarding node in the previous embodiment, the specific functions of the transceiver module 1001 and the processing module 1002 are as follows.

The transceiver module 1001 is configured to receive the first message sent by the third forwarding node, where the first message is an IPv4 message. For specific implementation, please refer to step 602 in the embodiment of Figure 6 .

The processing module 1002 is configured to generate a second message based on the first message, and send the second message to the second forwarding node, where the second message is an IPv6 message. For specific implementation, please refer to step 602 in the embodiment of Figure 6 .

The transceiver module 1001 is configured to receive a first control message sent by the second forwarding node, where the first control message is an IPv6 message, and the first control message is used to notify the second forwarding node of forwarding the second message. For specific implementation, please refer to step 604 in the embodiment of FIG. 6 .

The processing module 1002 is configured to generate a second control message based on the first control message when it is determined that the second forwarding node does not have an IPv4 address. For specific implementation, please refer to step 604 in the embodiment of FIG. 6 .

The transceiver module 1001 is configured to send a second control message to the third forwarding node, where the second control message is an IPv4 message, and the second control message carries the IPv6 address of the second forwarding node. For specific implementation, please refer to step 604 in the embodiment of FIG. 6 .

Optionally, the first control message carries an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address;

The processing module 1002 is used for:

Parse the first control message to obtain the IPv6 dedicated network identifier;

It is determined based on the IPv6 dedicated network identifier that the second forwarding node does not have an IPv4 address.

Optionally, the first control message is a Network Control Message Protocol ICMP message;

Optionally, the processing module 1002 is used for:

Obtain the locally stored IPv6 private network identifier. The IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address;

Optionally, the first control message carries the IPv6 address of the second forwarding node;

The processing module 1002 is used for:

Obtain the IPv6 address of the second forwarding node from the first control message to generate a second control message.

Optionally, the first control message is a Network Control Message Protocol ICMP message, and the first control message includes a second extension object, and the second extension object carries the IPv6 address of the second forwarding node;

The processing module 1002 is used for:

Obtain the IPv6 address of the second forwarding node from the second extension object.

Optionally, the first control message is a Network Control Message Protocol ICMP message, and the first control message includes a second ICMP message header, and the second ICMP message header carries the IPv6 address of the second forwarding node;

The processing module 1002 is used for:

Obtain the IPv6 address of the second forwarding node from the second ICMP message header.

Optionally, the first control message includes a first IPv6 header, and the first IPv6 header carries the IPv6 address of the second forwarding node;

The processing module 1002 is used for:

Obtain the IPv6 address of the second forwarding node from the first IPv6 message header.

Optionally, the first forwarding node locally stores the IPv6 address of the second forwarding node;

The processing module 1002 is used for:

Obtain the stored IPv6 address of the second forwarding node to generate a second control message based on the first control message and the IPv6 address of the second forwarding node.

Optionally, the second control message is a Network Control Message Protocol ICMP message;

Optionally, the second control message also carries an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address.

Optionally, the second forwarding node meets one of the following two conditions:

The intermediate node in the IPv6 network where the second forwarding node is located is not configured with an IPv4 address;

Or, the second forwarding node is configured with an IPv4 address, but the IPv4 address of the second forwarding node is not used externally.

Optionally, both the first message and the second message carry a time-to-live TTL, and the first control message indicates that the TTL of the second message has expired when the second message reaches the second forwarding node.

Optionally, the first message and the second message are path tracing messages.

In the scenario where the network device 1000 shown in Figure 10 is the second forwarding node in the previous embodiment, the specific functions of the transceiver module 1001 and the processing module 1002 are as follows.

The transceiver module 1001 is configured to receive a second message sent by the first forwarding node, where the second message is an IPv6 message. For specific implementation, please refer to step 603 in the embodiment of Figure 6 .

The processing module 1002 is used to determine that the second message cannot be forwarded currently and determine that the second message contains an IPv4 message. header, a first control message is generated based on the second message, the first control message indicates that the second forwarding node forwards the second message, and the first control message indicates that the second forwarding node does not have an IPv4 address. For specific implementation, please refer to step 603 in the embodiment of Figure 6 .

The transceiver module 1001 is configured to send the first control message to the first forwarding node. For specific implementation, please refer to step 603 in the embodiment of Figure 6 .

Optionally, the first control message carries an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address.

Optionally, the first control message carries the IPv6 address of the second forwarding node.

Optionally, the first control message includes a first IPv6 header, and the first IPv6 header carries the IPv6 address of the second forwarding node.

Optionally, the processing module 1002 is used for:

When the lifetime TTL of the second message is 1, it is determined that the second message cannot be forwarded at present.

Optionally, the second message is a path tracing message.

In the scenario where the network device 1000 shown in Figure 10 is the third forwarding node in the previous embodiment, the specific functions of the transceiver module 1001 and the processing module 1002 are as follows.

The transceiver module 1001 is configured to receive a second control message sent by the first forwarding node after sending the first message to the first forwarding node. The second control message is an IPv4 message and the second control message carries the information of the second forwarding node. IPv6 address, the first packet is an IPv4 packet. For specific implementation methods, reference can be made to step 601 and step 605 in the embodiment of FIG. 6 .

The processing module 1002 is configured to determine, based on the second control message, whether the second forwarding node forwards the first message. For specific implementation, please refer to step 605 in the embodiment of FIG. 6 .

Optionally, the processing module 1002 is also used to:

Parse the second control message to obtain the IPv6 address of the second forwarding node;

Displays the IPv6 address of the second forwarding node.

Optionally, the processing module 1002 is also used to:

Determine the IPv6 dedicated network identifier, which indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address;

Displays the IPv6 private network identification.

Optionally, the processing module 1002 is used for:

The second control message is parsed to obtain the IPv6 dedicated network identifier.

Optionally, the second control message indicates that when the first packet reaches the second forwarding node, the TTL of the first packet expires.

Optionally, the first message is a path tracing message.

The hardware structure involved in the embodiment of this application is introduced below.

Figure 11 is a schematic structural diagram of a device 1100 provided by an embodiment of the present application. Figure 12 is a schematic structural diagram of another device 1200 provided by an embodiment of the present application. The structure of these two devices is explained below.

It should be noted that the device 1100 or the device 1200 introduced below corresponds to any forwarding node in the above method embodiment. Each hardware, module and the above-mentioned other operations and/or functions in the device 1100 or the device 1200 are respectively used to implement the various steps and methods implemented by any forwarding node in the method embodiment. Regarding how the device 1100 or the device 1200 processes messages, For the detailed process, please refer to the above method embodiments for specific details. For the sake of simplicity, they will not be described again here. Each step of the above method embodiment is completed through the integrated logic circuit of the hardware in the processor of the device 1100 or the device 1200 or instructions in the form of software. The steps of the methods disclosed in conjunction with the embodiments of the present application can be directly implemented by a hardware processor for execution, or can be executed by a combination of hardware and software modules in the processor. The software module can be located in random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, registers and other mature storage media in this field. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware. To avoid repetition, the details will not be described here.

When the device 1100 corresponds to any of the above forwarding nodes, each functional module in the forwarding node is implemented using the software of the device 1100. In other words, the functional module included in the forwarding node is generated by the processor of the device 1100 after reading the program code stored in the memory.

When the device 1200 corresponds to any of the above forwarding nodes, each functional module in the forwarding node is implemented using the software of the device 1200. In other words, the functional module included in the forwarding node is generated by the processor of the device 1200 after reading the program code stored in the memory.

Referring to FIG. 11, FIG. 11 is a schematic structural diagram of a device 1100 provided by an embodiment of the present application. Optionally, the device 1100 is configured as the first forwarding node, the second forwarding node, or the third forwarding node shown in FIG. 4 . In other words, any forwarding node in the above method embodiment is optionally implemented through the device 1100.

The device 1100 is, for example, a network device. For example, the device 1100 is a switch, a router, etc. Alternatively, the device 1100 is, for example, a computing device. For example, the device 1100 is a host, a server or a personal computer. The device 1100 may be implemented by a general bus architecture.

Device 1100 includes at least one processor 1101, a communication bus 1102, a memory 1103, and at least one communication interface 1104.

The processor 1101 is, for example, a general-purpose central processing unit (CPU), a network processor (NP), a graphics processing unit (GPU), or a neural-network processing unit (NPU). ), a data processing unit (DPU), a microprocessor or one or more integrated circuits used to implement the solution of the present application. For example, the processor 1101 includes an application-specific integrated circuit (application-specific integrated circuit). integrated circuit (ASIC), programmable logic device (PLD) or a combination thereof. A PLD is, for example, a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a general array logic (GAL), or any combination thereof.

Communication bus 1102 is used to transfer information between the above-mentioned components. The communication bus 1102 can be divided into an address bus, a data bus, a control bus, etc. For ease of presentation, only one thick line is used in Figure 11, but this does not mean that there is only one bus or one type of bus.

The memory 1103 is, for example, a read-only memory (ROM) or other type of static storage device that can store static information and instructions, or a random access memory (random access memory, RAM) or a device that can store information and instructions. Other types of dynamic storage devices, such as electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disk storage, optical discs Storage (including compressed optical discs, laser discs, optical discs, digital versatile discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or can be used to carry or store desired program code in the form of instructions or data structures and can Any other media accessed by a computer, without limitation. The memory 1103 exists independently, for example, and is connected to the processor 1101 through the communication bus 1102 . The memory 1103 may also be integrated with the processor 1101.

Communication interface 1104 uses any transceiver-like device for communicating with other devices or communication networks. The communication interface 1104 includes a wired communication interface and may also include a wireless communication interface. The wired communication interface may be an Ethernet interface, for example. The Ethernet interface can be an optical interface, an electrical interface, or a combination thereof. The wireless communication interface may be a wireless local area networks (WLAN) interface, a cellular network communication interface or a combination thereof.

In specific implementation, as an embodiment, the processor 1101 may include one or more CPUs, such as CPU0 and CPU1 shown in FIG. 11 .

In specific implementation, as an embodiment, the device 1100 may include multiple processors, such as the processor 1101 and the processor 1105 shown in FIG. 11 . Each of these processors can be a single-core processor (single-CPU) or a multi-core processor (multi-CPU). A processor here may refer to one or more devices, circuits, and/or processing cores for processing data (such as computer program instructions).

In specific implementation, as an embodiment, the device 1100 may also include an output device and an input device. Output devices communicate with processor 1101 and can display information in a variety of ways. For example, the output device may be a liquid crystal display (LCD), a light emitting diode (LED) display device, a cathode ray tube (CRT) display device, or a projector (projector), etc. Input devices communicate with processor 1101 and can receive user input in a variety of ways. For example, the input device may be a mouse, a keyboard, a touch screen device or a sensing device, etc.

In some embodiments, the memory 1103 is used to store the program code 1110 for executing the solution of the present application, and the processor 1101 can execute the program code 1110 stored in the memory 1103. That is, the device 1100 can implement the message forwarding method provided by the method embodiment through the processor 1101 and the program code 1110 in the memory 1103.

The device 1100 in the embodiment of the present application can correspond to any forwarding node in the above method embodiments, and the processor 1101, communication interface 1104, etc. in the device 1100 can implement any forwarding node in the above method embodiments. functions and/or various steps and methods implemented. For the sake of brevity, no further details will be given here.

When the embodiment of the present application is implemented using the device 1100, in some embodiments, the transceiver module and the processing module in the network device 1000 shown in Figure 10 are software modules in the program code 1110 in the device 1100. The device 1100 The processor 1101 in the processor implements the functions of the transceiver module and the processing module in the network device 600 in FIG. 10 by executing the program code 1110.

Referring to Figure 12, Figure 12 is a schematic structural diagram of a device 1200 provided by an embodiment of the present application. Optionally, the device 1200 is configured as the first forwarding node or the second forwarding node or the third forwarding node shown in Figure 4 node. In other words, any forwarding node in the above method embodiments is optionally implemented through the device 1200.

The device 1200 is, for example, a network device. For example, the device 1200 is a switch, a router, etc. The device 1200 includes: a main control board 12010 and an interface board 12030.

The main control board is also called the main processing unit (MPU) or route processor card. The main control board 12010 is used to control and manage various components in the device 1200, including route calculation, device management, Equipment maintenance and protocol processing functions. The main control board 12010 includes: a central processing unit 12011 and a memory 12012.

The interface board 12030 is also called a line processing unit (LPU), line card or service board. The interface board 12030 is used to provide various service interfaces and implement data packet forwarding. Business interfaces include but are not limited to Ethernet interfaces, POS (Packet over SONET/SDH) interfaces, etc. Ethernet interfaces are, for example, Flexible Ethernet Clients (FlexE Clients). The interface board 12030 includes: a central processor 12031, a network processor 12032, a forwarding entry memory 12034, and a physical interface card (physical interface card, PIC) 12033.

The central processor 12031 on the interface board 12030 is used to control and manage the interface board 12030 and communicate with the central processor 12011 on the main control board 12010.

The network processor 12032 is used to implement packet forwarding processing. The network processor 12032 may be in the form of a forwarding chip. Specifically, the network processor 12032 is configured to forward the received message based on the forwarding table stored in the forwarding table memory 12034. If the destination address of the message is the address of the device 1200, then upload the message to the CPU (such as The central processor 12011) processes; if the destination address of the message is not the address of the device 1200, the next hop and outgoing interface corresponding to the destination address are found from the forwarding table based on the destination address, and the message is forwarded to the destination. The outbound interface corresponding to the address. Among them, the processing of uplink packets includes: processing of packet incoming interfaces, forwarding table search; processing of downlink packets: forwarding table search, etc.

The physical interface card 12033 is used to implement the docking function of the physical layer. The original traffic enters the interface board 12030 through this, and the processed packets are sent out from the physical interface card 12033. The physical interface card 12033 is also called a daughter card and can be installed on the interface board 12030. It is responsible for converting photoelectric signals into messages and checking the validity of the messages before forwarding them to the network processor 12032 for processing. In some embodiments, the central processor can also perform the functions of the network processor 12032, such as implementing software forwarding based on a general-purpose CPU, so that the network processor 12032 is not required in the physical interface card 12033.

Optionally, the device 1200 includes multiple interface boards. For example, the device 1200 also includes an interface board 12040. The interface board 12040 includes: a central processor 12041, a network processor 12042, a forwarding entry memory 12044, and a physical interface card 12043.

Optionally, the device 1200 also includes a switching network board 12020. The switching fabric unit 12020 can also be called a switching fabric unit (switch fabric unit, SFU). When the network device has multiple interface boards 12030, the switching network board 12020 is used to complete data exchange between the interface boards. For example, the interface board 12030 and the interface board 12040 can communicate through the switching network board 12020.

The main control board 12010 and the interface board 12030 are coupled. For example. The main control board 12010, the interface board 12030, the interface board 12040, and the switching network board 12020 are connected to the system backplane through the system bus to achieve intercommunication. In a possible implementation, an inter-process communication protocol (IPC) channel is established between the main control board 12010 and the interface board 12030, and the main control board 12010 and the interface board 12030 communicate through the IPC channel.

Logically, device 1200 includes a control plane and a forwarding plane. The control plane includes a main control board 12010 and a central processor 12031. The forwarding plane includes various components that perform forwarding, such as forwarding entry memory 12034, physical interface card 12033, and network processor. 12032. The control plane executes functions such as router, generates forwarding tables, processes signaling and protocol messages, configures and maintains device status. The control plane sends the generated forwarding tables to the forwarding plane. On the forwarding plane, the network processor 12032 is based on the control plane. The delivered forwarding table looks up the table and forwards the packets received by the physical interface card 12033. The forwarding table delivered by the control plane can be stored in the forwarding table item storage 12034. In some embodiments, the control plane and forwarding plane may be completely separate and not on the same device.

In the case where the forwarding node is implemented using the device 1200, in some embodiments, the transceiver module in the network device 600 shown in Figure 10 is equivalent to the physical interface card 12033 in the device 1200; the processing module of the network device 600 is equivalent to the network Processor 12032, CPU 12031 or CPU 12011.

It should be understood that the operations on the interface board 12040 in the embodiment of the present application are consistent with the operations on the interface board 12030, and will not be described again for the sake of simplicity. It should be understood that the device 1200 in this embodiment can correspond to any forwarding node in the above method embodiments, and the main control board 12010, interface board 12030 and/or 12040 in the device 1200 can implement the above method embodiments. For the sake of brevity, the functions of any forwarding node and/or the various steps implemented will not be described again here.

It is worth mentioning that there may be one or more main control boards, and when there are multiple main control boards, they can include the main main control board and the backup main control board. There may be one or more interface boards. The stronger the data processing capability of the network device, the more interface boards are provided. There can also be one or more physical interface cards on the interface board. There may be no switching network board, or there may be one or more switching network boards. When there are multiple switching network boards, load sharing and redundant backup can be realized together. Under the centralized forwarding architecture, network equipment does not need switching network boards, and the interface boards are responsible for processing the business data of the entire system. Under the distributed forwarding architecture, network equipment can have at least one switching network board, which enables data exchange between multiple interface boards through the switching network board, providing large-capacity data exchange and processing capabilities. Therefore, the data access and processing capabilities of network equipment with a distributed architecture are greater than those with a centralized architecture. Optionally, the network device can also be in the form of only one board, that is, there is no switching network board. The functions of the interface board and the main control board are integrated on this board. In this case, the central processor and main control board on the interface board The central processor on the board can be combined into one central processor on this board to perform the superimposed functions of the two. This form of equipment has low data exchange and processing capabilities (for example, low-end switches or routers and other networks equipment). The specific architecture used depends on the specific networking deployment scenario and is not limited here.

In other embodiments, embodiments of the present application also provide a message forwarding system. As shown in Figure 13, the message forwarding system 1300 includes a first forwarding node 1301, a second forwarding node 1302, and a third forwarding node 1303. The first forwarding node 1301 is an edge node of the IPv6 network, the second forwarding node 1302 is located in the IPv6 network, and the third forwarding node 1303 is located in the IPv4 network;

The third forwarding node 1303 is configured to: send the first message to the first forwarding node, where the first message is an IPv4 message;

The first forwarding node 1301 is configured to: receive the first message, generate a second message based on the first message, and send the second message to the second forwarding node, where the second message is an IPv6 message;

The second forwarding node 1302 is configured to: receive the second message, and generate a first control message based on the second message when it is determined that the second message cannot be forwarded currently and the second message has an IPv4 header. , the first control message is an IPv6 message, and the first control message is used to notify the second forwarding node of forwarding the second message;

The first forwarding node 1301 is also configured to: receive a first control message, and when the first forwarding node determines that the second forwarding node does not have an IPv4 address, generate a second control message based on the first control message, and send a third control message to the third forwarding node. Two control messages, the second control message is an IPv4 message, and the second control message carries the IPv6 address of the second forwarding node;

The third forwarding node 1303 is also configured to receive a second control message and determine, based on the second control message, whether the second forwarding node forwards the first message.

The detailed functions of each forwarding node in the above message forwarding system can be referred to the embodiment shown in FIG. 6 and will not be described again here.

Those of ordinary skill in the art can appreciate that the method steps and modules described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of both. In order to clearly illustrate the possible functions of hardware and software, Interchangeability, in the above description, the steps and compositions of each embodiment have been generally described according to functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. One of ordinary skill in the art may implement the described functionality using different methods for each specific application, but such implementations should not be considered beyond the scope of this application.

Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, devices and modules described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be described again here.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the modules is only a logical function division. In actual implementation, there may be other division methods. For example, multiple modules or components may be combined or may be Integrated into another system, or some features can be ignored, or not implemented. In addition, the coupling or direct coupling or communication connection between each other shown or discussed may be indirect coupling or communication connection through some interfaces, devices or modules, or may be electrical, mechanical or other forms of connection.

The modules described as separate components may or may not be physically separated. The components shown as modules may or may not be physical modules, that is, they may be located in one place, or they may be distributed to multiple network modules. Some or all of the modules can be selected according to actual needs to achieve the purpose of the embodiments of the present application.

In addition, each functional module in each embodiment of the present application can be integrated into one processing module, or each module can exist physically alone, or two or more modules can be integrated into one module. The above integrated modules can be implemented in the form of hardware or software function modules.

If the integrated module is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or contributes to the existing technology, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium , including several instructions to cause a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in various embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk and other media that can store program code. .

In this application, the terms "first" and "second" are used to distinguish the same or similar items with basically the same functions and functions. It should be understood that there is no logic or timing between "first" and "second" There are no restrictions on the number and execution order of the dependencies. It should also be understood that, although the following description uses the terms first, second, etc. to describe various elements, these elements should not be limited by the terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of various examples, the first information may be referred to as second information, and similarly, the second information may be referred to as first information. Both the first information and the second information may be information, and in some cases, may be separate and different information.

The term "at least one" in this application means one or more, and the term "plurality" in this application means two or more. The terms "system" and "network" are often used interchangeably in this article.

It should also be understood that the term "if" may be interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting." Similarly, depending on the context, the phrase "if it is determined..." or "if [stated condition or event] is detected" may be interpreted to mean "when it is determined..." or "in response to the determination... ” or “on detection of [stated condition or event]” or “in response to detection of [stated condition or event].”

The above description is only a specific implementation mode of the present application, but the protection scope of the present application is not limited thereto. Any person familiar with the technical field can easily think of various equivalent modifications within the technical scope disclosed in the present application. Or replacement, these modifications or replacements should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer program instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions according to the embodiments of the present application are generated in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable device. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another, e.g., the computer program instructions may be transmitted from a website, computer, server or data center to Wired or wireless transmission to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center integrated with one or more available media. The available media may be magnetic media (such as floppy disks, hard disks, magnetic tapes), optical media (such as digital video discs (DVD), or semiconductor media (such as solid state drives)), etc.

Those of ordinary skill in the art can understand that all or part of the steps to implement the above embodiments can be completed by hardware, or can be completed by instructing the relevant hardware through a program. The program can be stored in a computer-readable storage medium. As mentioned above, The storage medium can be read-only memory, magnetic disk or optical disk, etc.

The above descriptions are only optional embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application. within.

Claims

A message forwarding method, characterized in that the method is applied to a message forwarding system, the message forwarding system includes a first forwarding node, a second forwarding node and a third forwarding node, and the first forwarding node is An edge node of the sixth generation network protocol IPv6 network, the second forwarding node is located in the IPv6 network, and the third forwarding node is located in the fourth generation network protocol IPv4 network; the method includes:

The first forwarding node receives the first message sent by the third forwarding node, where the first message is an IPv4 message;

The first forwarding node generates a second message based on the first message, and sends the second message to the second forwarding node, where the second message is an IPv6 message;

The first forwarding node receives a first control message sent by the second forwarding node, where the first control message is an IPv6 message, and the first control message is used to notify the second forwarding node to forward the first The situation of the second message;

When the first forwarding node determines that the second forwarding node does not have an IPv4 address, it generates a second control message based on the first control message, and sends the second control message to the third forwarding node, so The second control message is an IPv4 message, and the second control message carries the IPv6 address of the second forwarding node.
The method of claim 1, wherein the first control message carries an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address;

The first forwarding node determines that the second forwarding node does not have an IPv4 address, including:

The first forwarding node parses the first control message to obtain the IPv6 dedicated network identifier;

The first forwarding node determines that the second forwarding node does not have an IPv4 address based on the IPv6 dedicated network identifier.
The method of claim 2, wherein the first control message is a Network Control Message Protocol ICMP message;

The first control message includes a first extension object, and the first extension object carries the IPv6 dedicated network identifier, or the first control message includes a first ICMP message header, and the first ICMP message header Carrying the IPv6 dedicated network identifier.
The method of claim 1, wherein the first forwarding node determines that the second forwarding node does not have an IPv4 address, including:

The first forwarding node obtains a locally stored IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address;

The first forwarding node determines that the second forwarding node does not have an IPv4 address based on the IPv6 dedicated network identifier.
The method according to any one of claims 1-4, characterized in that the first control message carries the IPv6 address of the second forwarding node;

The first forwarding node generates a second control message based on the first control message, including:

The first forwarding node obtains the IPv6 address of the second forwarding node from the first control message to generate the second control message.
The method of claim 5, wherein the first control message is an ICMP message, and the first control message includes a second extension object, and the second extension object carries the The IPv6 address of the second forwarding node;

The first forwarding node obtains the IPv6 address of the second forwarding node from the first control message, including:

The first forwarding node obtains the IPv6 address of the second forwarding node from the second extension object.
The method of claim 5, wherein the first control message is a Network Control Message Protocol (ICMP) message, and the first control message includes a second ICMP message header, and the second ICMP message The header carries the IPv6 address of the second forwarding node;

The first forwarding node obtains the IPv6 address of the second forwarding node from the first control message, including:

The first forwarding node obtains the IPv6 address of the second forwarding node from the second ICMP message header.
The method of claim 5, wherein the first control message includes a first IPv6 header, and the first IPv6 header carries the IPv6 address of the second forwarding node;

The first forwarding node obtains the IPv6 address of the second forwarding node from the first control message, including:

The first forwarding node obtains the IPv6 address of the second forwarding node from the first IPv6 message header.
The method according to any one of claims 1-4, characterized in that the first forwarding node locally stores the IPv6 address of the second forwarding node;

The first forwarding node generates a second control message based on the first control message, including:

The first forwarding node obtains the locally stored IPv6 address of the second forwarding node to generate the second control message based on the first control message and the IPv6 address of the second forwarding node.
The method according to any one of claims 1 to 9, characterized in that the second control message is a Network Control Message Protocol ICMP message;

The second control message includes a third extension object, the third extension object carries the IPv6 address of the second forwarding node, or the second control message includes a third ICMP header, and the third ICMP The message header carries the IPv6 address of the second forwarding node.
The method according to any one of claims 1 to 10, characterized in that the second control message also carries an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address.
The method of claim 11, wherein the second control message is a Network Control Message Protocol ICMP message;

The second control message includes a fourth extension object, the fourth extension object carries the IPv6 dedicated network identifier, or the second control message includes a fourth ICMP message header, and the fourth ICMP message header Carrying the IPv6 dedicated network identifier.
The method according to any one of claims 1-12, characterized in that the second forwarding node satisfies one of the following two conditions:

The intermediate node in the IPv6 network where the second forwarding node is located is not configured with an IPv4 address;

Alternatively, the second forwarding node is configured with an IPv4 address, but the IPv4 address of the second forwarding node is not used externally.
The method according to any one of claims 1 to 13, characterized in that both the first message and the second message carry a time to live (TTL), and the first control message indicates the arrival of the second message. The TTL of the second message times out when the second forwarding node is used.
The method of claim 14, wherein the first message and the second message are path tracing messages.
A message forwarding method, characterized in that the method is applied to a message forwarding system, the message forwarding system includes a first forwarding node, a second forwarding node and a third forwarding node, and the first forwarding node is An edge node of the sixth generation network protocol IPv6 network, the second forwarding node is located in the IPv6 network, and the third forwarding node is located in the fourth generation network protocol IPv4 network; the method includes:

After sending the first message to the first forwarding node, the third forwarding node receives a second control message sent by the first forwarding node, where the second control message is an IPv4 message and the second The control message carries the IPv6 address of the second forwarding node, and the first message is an IPv4 message;

The third forwarding node determines, based on the second control message, whether the second forwarding node forwards the first message.
The method of claim 16, wherein after the third forwarding node determines that the second forwarding node forwards the first message based on the second control message, the method further includes:

The third forwarding node parses the second control message to obtain the IPv6 address of the second forwarding node;

The third forwarding node displays the IPv6 address of the second forwarding node.
The method of claim 16 or 17, wherein the second control message is a Network Control Message Protocol ICMP message;

The second control message includes a third extension object, the third extension object carries the IPv6 address of the second forwarding node, or the second control message includes a third ICMP header, and the third ICMP The message header carries the IPv6 address of the second forwarding node.
The method according to any one of claims 16 to 18, characterized in that after the third forwarding node determines that the first forwarding node forwards the first message based on the second control message, the Methods also include:

The third forwarding node determines an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address;

The third forwarding node displays the IPv6 dedicated network identifier.
The method of claim 19, wherein the third forwarding node determines the IPv6 dedicated network identifier, including:

The third forwarding node parses the second control message to obtain the IPv6 dedicated network identifier.
The method of claim 20, wherein the second control message is a Network Control Message Protocol ICMP message;

The second control message includes a fourth extension object, the fourth extension object carries the IPv6 dedicated network identifier, or the second control message includes a fourth ICMP message header, and the fourth ICMP message header Carrying the IPv6 dedicated network identifier.
The method according to any one of claims 16-21, characterized in that the second control message indicates that when the first message reaches the second forwarding node, the survival time TTL of the first message times out. .
The method of claim 22, wherein the first message is a path tracing message.
A message forwarding method, characterized in that the method is applied to a message forwarding system, the message forwarding system includes a first forwarding node and a second forwarding node, the first forwarding node is a sixth generation network protocol An edge node of the IPv6 network, the second forwarding node is located in the IPv6 network; the method includes:

The second forwarding node receives the second message sent by the first forwarding node, and the second message is an IPv6 message;

When the second forwarding node determines that it cannot continue to forward the second message and determines that the second message has an IPv4 header, it generates a first control message based on the second message. A control message indicates that the second forwarding node forwards the second message, and the first control message indicates that the second forwarding node does not have an IPv4 address;

The second forwarding node sends the first control message to the first forwarding node.
The method of claim 24, wherein the first control message carries an IPv6 dedicated network identifier, and the IPv6 dedicated network identifier indicates that the intermediate node in the IPv6 network is not configured with an IPv4 address.
The method of claim 25, wherein the first control message is a Network Control Message Protocol ICMP message;

The first control message includes a first extension object, and the first extension object carries the IPv6 dedicated network identifier, or the first control message includes a first ICMP message header, and the first ICMP message header Carrying the IPv6 dedicated network identifier.
The method according to any one of claims 24 to 26, characterized in that the first control message carries the IPv6 address of the second forwarding node.
The method of claim 27, wherein the first control message is a Network Control Message Protocol ICMP message;

The first control message includes a second extension object, the second extension object carries the IPv6 address of the second forwarding node, or the first control message includes a second ICMP header, and the second ICMP The message header carries the IPv6 address of the second forwarding node.
The method of claim 27, wherein the first control message includes a first IPv6 header, and the first IPv6 header carries the IPv6 address of the second forwarding node.
The method according to any one of claims 24 to 29, characterized in that the second forwarding node determines that it cannot continue to forward the second message, including:

When the lifetime TTL of the second message is 1, the second forwarding node determines that it cannot continue to forward the second message currently.
The method of claim 30, wherein the second message is a path tracing message.
A message forwarding system, characterized in that the message forwarding system includes a first forwarding node, a second forwarding node and a third forwarding node, and the first forwarding node is an edge node of the sixth generation network protocol IPv6 network , the second forwarding node is located in the IPv6 network, and the third forwarding node is located in the fourth generation network protocol IPv4 network;

The third forwarding node is configured to: send a first message to the first forwarding node, where the first message is an IPv4 message;

The first forwarding node is configured to: receive the first message, generate a second message based on the first message, and send the second message to the second forwarding node. The message is an IPv6 message;

The second forwarding node is configured to: receive the second message, and when it is determined that the second message cannot be forwarded currently and the second message has an IPv4 header, based on the The second packet generates a first control message, the first control message is an IPv6 packet, and the first control message is used to notify the second forwarding node of forwarding the second packet;

The first forwarding node is also configured to receive the first control message, and when the first forwarding node determines that the second forwarding node does not have an IPv4 address, generate a second control message based on the first control message. and send the second control message to the third forwarding node, where the second control message is an IPv4 message, and the second control message carries the IPv6 address of the second forwarding node;

The third forwarding node is further configured to receive the second control message and determine, based on the second control message, whether the second forwarding node forwards the first message.
A network device, characterized in that the network device includes a memory and a processor;

The memory is used to store program instructions;

The processor is configured to call a program stored in the memory, so that the network device performs the method as described in any one of claims 1-15, or performs the method as described in any one of claims 16-23. method, or perform the method described in any one of claims 24-31.
A network device, characterized in that the network device includes a transceiver module and a processing module:

The transceiver module is used to perform transceiver-related operations in the method of any one of claims 1-15, and the processing module For performing operations other than the transceiver-related operations in the method of any one of claims 1-15; or,

The transceiver module is used to perform transceiver-related operations in the method of any one of claims 16-23, and the processing module is used to perform other transceiver-related operations in the method of any one of claims 16-23. operations other than; or,

The transceiver module is used to perform transceiver-related operations in the method described in any one of claims 24-31, and the processing module is used to perform transceiver-related operations in the method described in any one of claims 24-31. operations outside.
A computer-readable storage medium, characterized in that instructions are stored in the computer-readable storage medium, and when the instructions are run on a processor, the method of any one of claims 1-15 is implemented, or Implement the method described in any one of claims 16-23, or implement the method described in any one of claims 24-31.
A computer program product, characterized in that the computer program product contains instructions, and when the instructions are run on a processor, the method of any one of claims 1-15 is implemented, or the method of any one of claims 16-23 is implemented. The method described in any one of claims 24-31, or the method described in any one of claims 24-31.