WO2011079785A1

WO2011079785A1 - Method and apparatus for transmitting data packets

Info

Publication number: WO2011079785A1
Application number: PCT/CN2010/080416
Authority: WO
Inventors: 朱雷
Original assignee: 华为技术有限公司
Priority date: 2009-12-31
Filing date: 2010-12-29
Publication date: 2011-07-07
Also published as: CN102118792A; CN102118792B

Abstract

The embodiments of the present invention disclose a method and an apparatus for transmitting data packets, wherein the method comprises: a first end point transmits an initialization message to a second end point, wherein the initialization message includes the compression algorithm information of common packet headers; the first end point compresses the common packet headers of the data packets by using the compression algorithm indicated by the compression algorithm information of the common packet headers, and transmits the data packets with compressed common packet headers to the second end point, thereby reducing the overhead for transmission of protocol packet headers at radio air interfaces and consumption of transmission resource.

Description

A method for transmitting a data packet is set forth in the Chinese Patent Application No. 200910238887.7, filed on Dec. 31, 2009, the priority of the Chinese patent application entitled "A Method and Apparatus for Transmitting Data Packets" The entire contents of which are incorporated herein by reference. TECHNICAL FIELD The present invention relates to the field of wireless communications, and in particular, to a method and an apparatus for transmitting a data packet. Background technique

Relay technology is based on the original site, by adding some new Relay stations (or relay nodes), increasing the distribution density of sites and antennas. The new relay node and the original base station (the parent base station) are both connected by wireless, and there is no wired connection between the transmission network, and the downlink data first arrives at the parent base station, and then transmits to the relay node, and the relay node transmits the same to the relay node. For the end user, the upstream is the opposite. This approach narrows the distance between the antenna and the end user, improving the link quality of the terminal, thereby improving the spectrum efficiency and user data rate of the system.

In the existing Relay architecture scenario, the SCTP (Stream Control Transport Protocol) and its bearer control plane signaling are exposed in the air interface. The header area of the SCTP packet consumes air to some extent during transmission. Resources. SUMMARY OF THE INVENTION Embodiments of the present invention provide a method and an apparatus for transmitting a data packet, which implements a reduction in overhead of air interface resources.

An embodiment of the present invention provides a method for transmitting a data packet, where the data packet includes a universal header, and the method includes:

The first endpoint sends an initialization message to the second endpoint, where the initialization message includes: compression algorithm information of the general packet header; The first endpoint compresses a general header of the data packet by using a compression algorithm indicated by compression algorithm information of the universal header;

Transmitting the data packet compressed by the universal header to the second endpoint.

An embodiment of the present invention further provides a data transmission apparatus, including: a sending unit and a compression unit, where

The sending unit is configured to send an initialization message to the peer node, where the initialization message includes: a compression algorithm information of a general packet header; and sending, to the peer node, the data packet processed by the compression unit ;

The compression unit is configured to compress a general header of the data packet by using a compression algorithm indicated by compression algorithm information of the universal header.

The embodiment of the present invention further provides a method for transmitting a data packet, where the data packet includes a general packet header, and the method includes:

The second endpoint receives the initialization message sent by the first endpoint, where the initialization message includes: compression algorithm information of the general packet header;

Receiving, by the second endpoint, a data packet that is compressed by the first endpoint by using a compression algorithm indicated by the compression algorithm information of the universal packet header to compress the universal header of the data packet;

The second endpoint decompresses the compressed data packet.

The method of the embodiment of the present invention compresses the general header of the data packet, so that the size of the general header of the transmitted data packet is reduced, thereby reducing the overhead of the wireless air interface transmission protocol header, and Transmission resource; % consumption. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flowchart of a method for transmitting a data packet according to an embodiment of the present invention; FIG. 2 is a flowchart of still another method for transmitting a data packet according to an embodiment of the present invention; A schematic structural diagram of an SCTP data packet in the embodiment of the present invention;

4 is a schematic structural diagram of a general header of an SCTP data packet according to an embodiment of the present invention; FIG. 5 is a schematic structural diagram of a data block of an SCTP data packet according to an embodiment of the present invention; FIG. 6 is a schematic structural diagram of a complete SCTP data packet according to an embodiment of the present invention; FIG. 8 is a schematic diagram of an SCTP data packet transmission according to an embodiment of the present invention; FIG. 9 is a schematic diagram of an IR message format according to an embodiment of the present invention;

FIG. 10 is a flowchart of a transmission between a compressor and a decompressor according to an embodiment of the present invention; and FIG. 11 is a schematic diagram of a data packet transmission apparatus according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of a method for transmitting a data packet according to an embodiment of the present invention. The data packet includes a general header and at least one data block, and includes a data block header in the data block; the data packet may be an SCTP data packet based on the SCTP protocol, or may be a common one similar to the SCTP data packet. The header and the different data blocks are used to transmit packets of multiple steams.

The method for transmitting a data packet includes:

Step 101: The first endpoint sends an IR (Initiate and Refresh) message to the second endpoint, which is referred to as an initialization message, and may be sent in the form of an IR package. The initialization message includes: compression algorithm information of the general header.

The first endpoint may be a relay node, and correspondingly, the second endpoint may be a base station corresponding to the relay node. The first endpoint and the second endpoint may also be the same as the relay node or the base station, or other devices that can establish an association relationship similar to the SCTP Association.

The compression algorithm information of the general header may include: indication information of a compression algorithm for a general header of the data packet agreed by the first endpoint and the second endpoint, so that the second endpoint is in the receiving After the initialization message, the compression algorithm of the general header can be used to learn the compression algorithm of the corresponding general header, and then the compression algorithm is used to decompress the general header of the subsequently received data packet. The compression algorithm information of the universal header can be represented in various ways, such as identification, indication, number, index, and the like.

Step 102: The first endpoint compresses a general header of the data packet by using a compression algorithm indicated by the compression algorithm information of the universal packet header.

In the compression process, the first endpoint may compress the static header field in the general header of the packet using the compression algorithm indicated by the compression algorithm information of the general header described above, and retain the dynamic header field in the universal header. You can also select a partial dynamic header field to compress.

Step 103: Send a data packet compressed by the general header to the second endpoint.

Further, the method may further include:

The first endpoint sends a second initialization message to the second endpoint, where the second initialization message includes: compression algorithm information of the data block header in the data packet;

The first endpoint compresses the data block header of the data packet by using a compression algorithm indicated by the compression algorithm information of the data block header;

After that, the data packet compressed by the data block header is sent to the second endpoint.

Vacancies, the compression of the general header of the data packet is achieved, thereby reducing the consumption of transmission resources.

Another method for transmitting a data packet according to an embodiment of the present invention is shown in FIG. The data packet includes a general header and at least one data block, and includes a data block header in the data block; the data packet may be an SCTP data packet based on the SCTP protocol, or may be a common one similar to the SCTP data packet. The header and the different data blocks are used to transmit packets of multiple steams. The method for transmitting a data packet includes:

Step 201: The first endpoint sends an initialization message to the second endpoint, where the initialization message includes: compression algorithm information of the general packet header, and compression algorithm information of the data block header. The first endpoint may be a Relay node, and correspondingly, the second endpoint may be a base station corresponding to the Relay node. The first endpoint and the second endpoint may also be the same as the Relay node or the base station, or other devices that can establish an association relationship similar to the SCTP Association.

The compression algorithm information of the general header may include: indication information of a compression algorithm for a general header of the data packet agreed by the first endpoint and the second endpoint, so that the second endpoint may pass the initialization message after receiving the initialization message The compression algorithm information of the general packet header learns the compression algorithm of the corresponding general packet header, and then uses the compression algorithm to decompress the general header of the subsequently received packet. The compression algorithm information of the general header can be expressed in various ways, such as number, index, and the like.

Step 202: The first endpoint compresses a general packet header of the data packet by using a compression algorithm indicated by the compression algorithm information of the general packet header, and performs a compression algorithm indicated by the compression algorithm information of the data packet header to perform packet headers of the data packet. Compressed separately;

The above-mentioned compression of each data block header of the data packet specifically refers to: compressing each data block header of all data blocks in the data packet separately; or compressing each data block header of a partial data block in the data packet separately.

Since one data packet can include multiple data blocks, different types of data blocks can be used to transmit services of different purposes, so different compression algorithms of different data block headers can be set separately for different types of data blocks; Need to select some of the data block headers in the packet for compression.

Optionally, in order to facilitate the second endpoint to receive the data packet sent by the first endpoint, the compressed state of each data block in the data packet is obtained, and the first endpoint may simultaneously carry the data block identifier in the initial message, and a compression algorithm of a data block header corresponding to different data blocks represented by different data block identifiers, so that after receiving the initialization message, the second endpoint can decompress each data block header using a corresponding header compression algorithm; The point may also carry the identifiers of different data blocks in the data packet and the compression flags corresponding to the different data blocks in the initial message. After the second endpoint receives the initialization message, it can conveniently identify the compression state of each data block, and decompress the corresponding data block header according to the identifier of the different data block and the compression flag corresponding to the different data blocks respectively. Do not decompress.

Optionally, during the compression process, the first endpoint may compress the static header field in the universal header of the data packet by using a compression algorithm indicated by the compression algorithm information of the universal header, and retain the dynamic header field in the universal header. The compression algorithm indicated by the compression algorithm information of the data block header is separately compressed for the static words in each data block header of the data packet, and the dynamic header field in each data block header is reserved.

Step 203: Send, to the second endpoint, a data packet compressed by the general header and the data block header.

Vacancies enable flexible compression of the general header of the packet and the header of the data block, thus reducing the consumption of transmission resources.

The method provided by the embodiment of the present invention is further described below by taking the SCTP packet transmission in the scenario where the relay node exists as an example. The method provided by the embodiment of the present invention is also applicable to other similar scenarios.

FIG. 3 is a schematic structural diagram of an SCTP data packet according to an embodiment of the present invention. An SCTP data packet includes a common header and at least one chunk. The format of the general header of the SCTP packet is shown in Figure 4. The structure of a data block of the SCTP packet is shown in Figure 5; the structure of a complete SCTP packet is shown in Figure 6. For an SCTP Association peer, different types of data blocks can be used for different purposes such as signaling, maintaining SCTP-associated messages, and user data, so the data block type in the SCTP packet can include at least one of the following: :

User data ( Payload Data ) data block;

Initialize an Initiation data block;

Initialization confirmation (Initiation Acknowledgement); The data block selects a 'Selective Acknowledgement' data block;

Heartbeat Request data block;

Heartbeat Acknowlegement data block;

Abandon (ABORT) data block;

Shutdown the data block;

Stop confirmation (Shutdown Acknowledgement) data block;

Operation Error (Data Error) data block;

State cookie (State Cookie) data block;

LL acknowledge (cookie Acknowledgement) data block;

Reserved for Explicit Congestion Notification Echo data block;

Reserved for Congestion Window Reduced data block; Shutdown Complete data block.

The header structure of the Payload Data block is shown in Figure 7. When the user data is transmitted, the utilization of the air interface transmission resource is reduced because the Palyload Data data block in the SCTP data packet includes a specific header overhead in the extra data block. In the embodiment of the present invention, a Payload Data data block is taken as an example, and a method of applying ROHC (Robust Header Compression) header compression technology in an SCTP data packet is designed according to the characteristics of the SCTP protocol.

The SCTP protocol is used as a transport protocol, and a typical transport protocol with multiple transport data blocks, including the following features: The general header structure is basically unchanged, and the variable part can be predicted by some specific methods; and the SCTP protocol header structure Support for multiple chunks, different chunks for transporting their own streams, and supporting multiple different end points, ie multihoming.

Based on the above features, as shown in FIG. 8, the embodiment of the present invention provides a schematic diagram of SCTP data packet transmission. An SCTP association is established between the first endpoint and the second endpoint, where the first endpoint and the second endpoint may be referred to as an SCTP Association Peer. A ROCH compression process is applied to an SCTP Association, applying and maintaining a specific set of R0HC header compression contexts, a set of header compression contexts using the same, or different compression algorithms. The method includes a universal compression context for compressing a universal header field, and one or more slave header compression contexts subordinate to the SCTP association, corresponding to compression algorithms of different data block headers; and may also allow occurrence of no dependent header compression context. Happening.

In the process shown in FIG. 8, the first endpoint compresses the general header using a compression algorithm represented by the ROHC profile 0x0201; compresses the data block (chunk) carrying the stream using the compression algorithm represented by the ROHC profile 0x02011 # 1 header; use ROHC profile 0x02012 to compress the data block #2 header of the bearer stream.

On the ROHC header compression process, the first endpoint initiates a header compression context initialization (Initiation and Refresh), which includes an SCTP protocol header general header compression flag and a ROCH header compression context identifier, in which a SCTP can also be formulated. A packet header compression algorithm for different types of data blocks applied by multiple streams (streams) to be transmitted in a protocol; a header compression algorithm of the data block and a general header compression identifier may be used in association.

Since the headers of multiple data blocks are all in the same SCTP data packet, the association relationship between multiple data block headers and the compression algorithm of the general header can be set, and the compression algorithm identifier of a certain data block header can be considered. The compression algorithm of other data block headers or general headers that can be associated with it can be applied to the compression processing of one data packet at the same time, and cannot be used simultaneously with other protocol header compression algorithms.

During the compression and transmission of the packet header, multiple associated contexts work simultaneously, and the header compression algorithms of different data blocks can work independently of each other. For example, the general header compression context may not work, and the compression context of multiple stream transport blocks works; or the general header compression context works, and the compression context of other stream transport blocks does not work. The above work specifically refers to compressing the corresponding header by using a compression algorithm.

Specific methods may include: Defining a new SCTP generic ROHC header compression profile, The number is rofile_value_201.

The format of the general header of the SCTP packet is shown in Figure 4, where the source port number and the destination port number are static header fields; the Verification Tag is initiated by the SCTP association. The endpoint is generated and carried by the Initiate Tag in the Initiation data block and serves as the value in the Verification Tag field of the subsequent SCTP message general header field; the Checksum field is a field for checking and protecting the integrity of the current SCTP packet, where Can be used as a dynamically changing header field. Therefore, the static header field can be compressed, thereby reducing the use of resources by the static header field during transmission.

In addition, define one or more data blocks ROHC header compression profile. The ROHC header compression profile of an SCTP Payload Data block is defined as profile_value_2011. The packet header compression profile represented by the number profile_value_2011 is associated with the packet header compression profile represented by the number profile_value_201. That is, the packet header compression profile represented by the number profile_value_2011 can be triggered and used under the condition that the packet header compression profile represented by the number profile_value_201 is used.

The header structure of the Payload Data block is shown in Figure 7. Where Type=0 is the fixed identifier of the Payload Data data block; the Reserved (reserved) 5 bits are reserved bits, and the value should be set to "0"; the U bit identifier is set to "1". The identifier is sent out of order. The data block, and vice versa is the data block sent in order; the B bit setting "1" indicates that the fragment is the starting data slice; the E bit is set to "1" to indicate that the data piece is the last data piece; The length of the block is different for different SCTP packets; the TSN (transmission sequence number) is the TSN of the current data block, and the TSN is generally a monotonically increasing value; the Stream Identifier S indicates the stream identifier to which the current user data belongs; Payload The Protocol Identifier is represented by the SCTP protocol and is recognized by the upper protocol stack. This header field is also a static header field. Therefore, the static header field can be compressed, thereby reducing the use of resources by the static header field during transmission.

Since there are more than one Payload Data data block for SCTP packets, the ROHC header compression of the Payload Data block associated with an SCTP Universal ROHC Header Compression Profile is compressed. The profile can be multiple.

It is also possible to define an ROHC header compression profile of traffic data with specific characteristics transmitted by the data block. For example, the transport data block of the transmission signaling may define a header compression profile separately.

The interaction between the compressor and the decompressor for the SCTP packets defined above is described below. Wherein, the compressor is located at the first end point, and the decompressor is located at the second end point.

First, the compressor sends an IR message that is used to establish the header compression context. The format of the message is as shown in FIG. 9, where CID represents a Context ID (Context ID), the Add-CID octet field includes a short ROHC header compression context identifier, and 0-2 octets of CID is a long header compression context identifier; The cyclic redundancy code check, the profile specific information is compression algorithm specific information, and the profile specific information includes the chunk identifier in the SCTP data packet.

The profile id newly defined in the embodiment of the present invention includes:

IP/SCTP common header: profile 0x0201, This profile is the general header compression profile for IP/SCTP.

IP/SCTP user data: Profile 0x02011, this profile is the compression profile of the IP/SCTP user data block header.

The transmission process between the compressor and the decompressor is shown in Figure 10, including

Step 105: The compressor sends an IR package (initialization message) to the decompressor, and adds profile 0x0201 in the profile field of the message to start the SCTP universal header compression algorithm.

Step 110: The compressor sends the SCTP data packet compressed by the general header to the decompressor, where the Compressed Package Format represents the compressed packet format.

Step 115: The compressor sends another IR Package to the decompressor, adds a data block identifier of profile 0x02011 and chunk #1 in the profile field, and starts a packet header compression algorithm of the user data block of chunk #1. The compressor compresses both the generic header of the SCTP packet and the user data block header of chunk #1.

Step 120: The compressor sends the SCTP data packet compressed to the general packet header and the user data block header of the chunk #1 to the decompressor. The method provided by the embodiment of the present invention implements a packet header compression technology for a transport protocol header with multiple transport data blocks, and performs flexible compression on a general header and a data block header of the data packet, thereby further reducing the wireless air interface transmission protocol. The overhead of the header.

A person skilled in the art can understand that all or part of the steps in the above embodiments may be implemented by hardware related to program instructions. The above program may be stored in a computer readable storage medium, and the foregoing storage medium may be a ROM. /RAM, disk, CD, etc.

FIG. 11 is a diagram showing a data packet transmission apparatus according to an embodiment of the present invention, which is capable of communicating with a peer node, and implementing the method provided in the foregoing embodiment, where the apparatus includes: a sending unit 1101, and a compressing unit 1102, where :

The sending unit 1101 is configured to send an initialization message to the peer node, where the initialization message includes: compression algorithm information of the general packet header; and sending the data packet processed by the compression unit 1102 to the opposite node;

The compressing unit 1102 is configured to compress the general header of the data packet by using a compression algorithm indicated by the compression algorithm information of the general header.

Further, the initialization message sent by the sending unit may further include: compression algorithm information of the data block header; correspondingly, the compression unit is further configured to: use a compression algorithm indicated by the compression algorithm information of the data block header to each of the data packet The data block header is compressed separately. The compression algorithm indicated by the compression algorithm information of the above data block header may be separately set for different types of data blocks.

The compression unit may separately compress a portion of the data block headers in the data packet using a compression algorithm indicated by the compression algorithm information of the data block header.

The compression unit may compress the static header field in the general header of the packet using a compression algorithm indicated by the compression algorithm information of the general header, and retain the dynamic header field in the general header.

The compression unit may also separately compress the static words in each data block header of the data packet by using a compression algorithm indicated by the compression algorithm information of the data block header, and retain the dynamic header field in each data block header. Optionally, the sending unit may further send a second initialization message after sending the first initialization message to the peer node, where the second initialization message includes: compression algorithm information of the data block header in the data packet; correspondingly, the compression unit Also used to compress the data block header of the data packet by using a compression algorithm indicated by the compression algorithm information of the data block header.

Optionally, the initialization message sent by the sending unit may further include: an identifier of a different data block in the data packet, and a compression flag corresponding to the different data blocks, respectively, so that the peer node receives the initialization message, The corresponding data block header is decompressed or not decompressed according to the identifiers of different data blocks and the corresponding compression flags of different data blocks.

The packet transmission device may be specifically a relay node, or a base station, or other communication device capable of transmitting such data packets.

The data packet transmission apparatus provided by the embodiment of the present invention implements a packet header compression technology for a transport protocol header with multiple transport data blocks, and performs flexible compression on a general header and a data block header of the data packet, thereby further reducing wireless The overhead of the air interface transport protocol header.

It should be specially noted that all or part of the above units can be integrated into the chip. The functional units in the various embodiments of the present invention may be integrated into one processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. The above integrated modules can also be stored in a computer readable storage medium if they are implemented in the form of software functional modules and sold or used as separate products. The storage medium mentioned above may be a read only memory, a magnetic disk or an optical disk or the like.

The drawings and the related description are merely illustrative of the principles of the invention and are not intended to limit the scope of the invention. For example, the message names and entities in various embodiments of the present invention may vary depending on the network, and some messages may be omitted. Therefore, any modifications, equivalents, improvements, etc. made within the spirit and scope of the present invention are included in the scope of the present invention.

Although the invention has been illustrated and described with reference to certain preferred embodiments of the invention It will be apparent to those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention.

Claims

Rights request

A method for transmitting a data packet, the data packet comprising a universal header, the method comprising:

The first endpoint sends an initialization message to the second endpoint, where the initialization message includes: compression algorithm information of the general packet header;

The first endpoint compresses a general header of the data packet by using a compression algorithm indicated by compression algorithm information of the universal header;

2. The method of claim 1 wherein:

After the data packet compressed by the universal header is sent to the second endpoint, the method further includes:

The first endpoint sends a second initialization message to the second endpoint, where the second initialization message includes: compression algorithm information of a data block header in the data packet;

The first endpoint compresses a data block header of the data packet by using a compression algorithm indicated by compression algorithm information of the data block header;

Transmitting the data packet compressed by the data block header to the second endpoint.

3. The method of claim 1 wherein:

The data packet further includes at least one data block, the data block includes a data block header; the initialization message further includes: compression algorithm information of the data block header; the first endpoint uses the data block header The compression algorithm indicated by the compression algorithm information separately compresses each data block header of the data packet;

The sending, to the second endpoint, the data packet compressed by the universal header includes: transmitting, to the second endpoint, the compressed data of the universal header and the data packet header Package.

The method according to claim 2 or 3, wherein the compression algorithm indicated by the compression algorithm information of the data block header is separately set for different types of data blocks.

The method according to claim 2 or 3, wherein the first endpoint compresses a data block header of the data packet by using a compression algorithm indicated by the compression algorithm information of the data block header, specifically including :

The first endpoint compresses a portion of the data packet headers in the data packet using a compression algorithm indicated by the compression algorithm information of the data block header.

The method according to claim 2 or 3, wherein the initialization message further includes: an identifier of a different data block in the data packet, and a compression flag corresponding to the different data block, so that the After receiving the initialization message, the second endpoint decompresses or decompresses the corresponding data block header according to the identifier of the different data block and the compression flag corresponding to the different data blocks.

7. The method according to claim 2 or 3, wherein the data packet is a flow control transmission protocol SCTP data packet,

Before the first endpoint sends the initialization message to the second endpoint, the method further includes:

Establishing, by the first endpoint, an SCTP association with the second endpoint;

The compression algorithm of the universal header and the compression algorithm of the data block header are compressed for a common header and/or a data packet header of one or more data packets in the SCTP association, which are set for the SCTP association. In the process.

The method according to any one of claims 1 to 3, wherein the first endpoint uses a compression algorithm indicated by the compression algorithm information of the universal header to a general packet of the data packet. The header is compressed, including:

The first endpoint compresses a static header field in a general header of the data packet using a compression algorithm indicated by the compression algorithm information of the universal header, and reserves a dynamic header field in the universal header.

The method according to claim 2 or 3, wherein the first endpoint compresses a data block header of the data packet by using a compression algorithm indicated by the compression algorithm information of the data block header, specifically including: :

The first endpoint uses a compression algorithm indicated by the compression algorithm information of the data block header to separately compress static words in each data block header of the data packet, and retains a dynamic header field in each data block header. Field.

10. A method according to any one of claims 1-3, characterized in that

The first endpoint is a relay node, and the second endpoint is a base station; or

The first endpoint is a relay node, and the second endpoint is a relay node; or the first endpoint is a base station, and the second endpoint is a relay node.

A packet transmission device, capable of communicating with a peer node, the method comprising: a sending unit and a compression unit, where

12. Apparatus according to claim 11 wherein: The initialization message sent by the sending unit further includes: compression algorithm information of the data block header;

The compression unit is further configured to separately compress each data block header of the data packet by using a compression algorithm indicated by the compression algorithm information of the data block header.

13. A method of transmitting a data packet, the data packet comprising a universal header, the method comprising:

The second endpoint decompresses the compressed data packet.

14. The method according to claim 13, further comprising:

The second endpoint receives the second initialization message sent by the first endpoint, where the second initialization message includes: compression algorithm information of a data block header in the data packet;

Receiving, by the second endpoint, a data packet that is compressed by the first endpoint by using a compression algorithm indicated by compression algorithm information of the data block header to compress a data block header of the data packet;

The second endpoint decompresses the compressed data packet according to a compression algorithm indicated by the compression algorithm information of the data block header.

15. The method of claim 13 wherein:

The data packet further includes at least one data block, the data block includes a data block header; the initialization message further includes: compression algorithm information of the data block header; the second endpoint receives the first endpoint using the The compression algorithm indicated by the compression algorithm information of the general packet header compresses the data packet of the general packet header of the data packet, and specifically includes: The second endpoint receives the compression algorithm indicated by the compression algorithm information of the universal header of the first endpoint, compresses a general header of the data packet, and uses the compression algorithm information indicated by the data packet header to compress The algorithm separately compresses the data packet of each data block header of the data packet;

The second endpoint decompresses the compressed data packet, including:

The second endpoint decompresses the compressed data packet according to a compression algorithm indicated by the compression algorithm information of the universal packet header and a compression algorithm indicated by the compression algorithm information of the data block header.

16. A method according to any one of claims 13-15, characterized in that

The initial message further includes an identifier of a different data block in the data packet, and a compression flag corresponding to the different data block, respectively, so that the second endpoint, after receiving the initialization message, is different according to the The identifier of the data block and the compression flag corresponding to the different data blocks respectively decompress or decompress the corresponding data block header.