WO2009000119A1

WO2009000119A1 - Data transmission system and transmission method thereof

Info

Publication number: WO2009000119A1
Application number: PCT/CN2007/003559
Authority: WO
Inventors: Yuxiang Feng
Original assignee: Zte Corporation
Priority date: 2007-06-26
Filing date: 2007-12-12
Publication date: 2008-12-31
Also published as: CN101079889A

Abstract

A data transmission system is disclosed. It includes: a data sending device, for compressing the XML component in the soap message, packaging the compressed data to the soap message as attachments, and sending the packaged soap message to the data receiving device; a data receiving device, for extracting the attachments of the soap message after receiving the soap message, and decompressing the attachments to get the XML component .A data transmission method is also disclosed. It includes the following steps: the data sending side compresses the XML component in the soap message, packages the compressed data to the soap message as attachments, and sends the packaged soap message to the data receiving side; the data receiving side extracts the attachments of the soap message after receiving the soap message, and decompresses the attachments to get the XML component.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of computer communications, and in particular to a data transmission system and a method for reducing network bandwidth occupied by a Soap protocol by using a data compression algorithm. BACKGROUND In the current field of computer communication, in order to meet the needs of communication between heterogeneous devices, the WebService protocol has been increasingly applied. The encapsulation protocol for data in the WebService interface is the Soap protocol, which is usually transmitted using the Http protocol. The relationship between WebService, Soap and XML is shown in Figure 1. The Soap protocol uses XML statements to describe the data content. It has the advantage of being easy to read, but the data redundancy is large and there are a large number of description characters. Nowadays, the demand for data communication is increasing through the wireless network. Users using wireless Internet access to obtain information is a major trend in communication development. Users wireless Internet access, the same communication protocol as the ordinary computer Internet access, all data is carried on the IP protocol, but the user access method is wireless. If you want to use wireless Internet access, then the Soap protocol will be used more and more. However, the wireless access method makes the network bandwidth very limited and valuable, can not meet the needs of users, and limits the development of wireless Internet services. Therefore, when using the Soap protocol to communicate, the shortcomings of the XML statement information redundancy will be very obvious. In order to resolve this contradiction, many researchers have now proposed their own methods. However, some complex algorithms are used to encode and compress the data stream. The compression method is to recombine and optimize the strings without destroying the data encoding format (UTF8, gb2312, etc.). This approach is similar to the way huffman coding. The standard methods for reading and manipulating XML data streams are the DOM (Document Object Model) approach and the SAX (Simple API for XML) approach. The methods proposed by the researchers are all modified and applied to the DOM or SAX methods, which can directly parse the data stream. The disadvantage is that it is difficult to implement, because there is no ready-made implementation code to use, and more importantly, the compression ratio is very low, and the bandwidth occupation problem cannot be fundamentally solved. In addition, with the improvement of CPU computing power, the computing power of mobile phone terminals is now getting stronger and stronger. This makes it possible for mobile terminals to perform some computationally expensive but very versatile algorithms. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a data transmission system and a transmission method thereof. According to the data transmission system of the present invention, the method includes: a data transmitting device, configured to compress the XML portion in the Soap message and package the compressed data as an accessory into the Soap message, and send the packaged Soap message to the data receiving And a data receiving device, configured to: after receiving the Soap message, extract an attachment of the Soap message, and decompress the accessory to obtain an XML part. The data sending device includes: a data compression module, configured to compress the XML portion in the Soap message to obtain binary data; and a first data recombining module, configured to reassemble the compressed binary data as an attachment into the Soap message and send the Soap message To the data receiving device, wherein the data compression module identifies the compression method by the attribute value of the content type field. The data receiving apparatus includes: a second data recombining module, configured to extract the attribute values of the binary data and the content type field in the received Soap message; and a data decompression module, configured to decompress the binary data according to the attribute value. Further, the above attribute value is one of the following: lzw data corresponding to the lzw algorithm, k78 data corresponding to the 1ζ78 algorithm, and 1ζ77 data corresponding to the 1ζ77 algorithm. At the same time, the attribute value is one of the following: lzw data / XML, 1ζ78 data / XML, 1ζ 77 data / XML. According to the data transmission method of the present invention, the method includes the following steps: Step S302: The data sending end compresses the XML part of the Soap message and packages the compressed data as an attachment into the Soap message, and sends the packaged Soap message. To the data receiving end; in step S304, after receiving the Soap message, the data receiving end extracts the attachment of the Soa message and decompresses the attachment to obtain the XML part. The step S302 includes: Step S302-2, according to the sender, compressing the XML part in the Soap message to obtain binary data; Step S302-4, recombining the compressed binary data as an attachment into the Soap message and Soap The message is sent to the data receiving end, where the data compression module identifies the compression method by the attribute value of the content type field. Step S304 includes: step S304-2, the data receiving end extracts the binary data in the received Soap message and the attribute value of the content type field; and step S304-4, the binary data is solved according to the attribute value. compression. The above attribute value is one of the following: lzw data corresponding to the lzw algorithm, 1ζ78 data corresponding to the 1ζ78 algorithm, and 1ζ77 data corresponding to the 1ζ77 algorithm. At the same time, the attribute value is one of the following: lzw data / XML, 1ζ78 data / XML, 1ζ77 data / XML. Through the above aspects of the present invention, the implementation codes of the algorithms (lzw, 1ζ77, 1ζ78) are all ready-made and convenient to implement; the compression ratio is particularly large, compared with the compression algorithms of the same kind proposed by various researchers, the compression of this implementation The effect is the best; the scalability is strong, and new data compression algorithms can be applied directly in the future. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, In the drawings: FIG. 1 is a diagram showing a relationship between a prior art WebService, Soap, and XML; FIG. 2 is a structural diagram showing a data transmission system according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION The preferred embodiments of the present invention are described in the following with reference to the drawings, and the preferred embodiments described herein are only used to illustrate and explain the present invention. It is not intended to limit the invention. In the present embodiment, FIG. 2 is a block diagram showing a data transmission system according to an embodiment of the present invention. As shown in FIG. 2, the data transmission system includes: a data sending device 202, configured to compress an XML portion in a Soap message, and package the compressed data as an accessory into a Soap message, and send the packaged Soap message to the data. a receiving device; the data receiving device 204, configured to: after receiving the Soa message, extract an attachment of the Soap message, and decompress the accessory to obtain an XML part. The data sending device 202 includes: a data compression module 202-2, configured to compress the XML portion in the Soap message to obtain binary data, and the algorithm used is a traditional compression algorithm, such as LZ77, LZ78, LZW, etc., data compression module ^ ! The xml part of the Soap message is compressed to obtain a series of binary data; the first data recombining module 202-4 is configured to reassemble the compressed binary data as an attachment into the Soap message and send the Soap message to the data receiving apparatus. . The data receiving apparatus 204 includes: a second data recombining module 204-2, configured to extract the attribute values of the binary data and the content type field in the received Soap message, and the recombining module extracts the binary data in the attachment. Then, using the data decompression module, the data block is decompressed using the compression algorithm identified by the Content-Type field to obtain the original xml format data; and the data decompression module 204-4 is used to perform the attribute value on the binary data. Decompressed, it uses the same algorithm as the originator. This kind of processing is similar to the way Http transfers file data (such as pictures of web pages, etc.). When packing, the sender indicates the compression method by the attribute value of the Content-Type field. What needs to be explained here is: The message reassembly module extends the attribute value of the Content-Type field, and adds the following attributes: lzwdata, lz78data, lz77data, which correspond to the lzw algorithm, the 1ζ78 algorithm, and the 1ζ77 algorithm, respectively. The data compression module identifies the compression method by the attribute value of the content type field. In the present embodiment, FIG. 3 is a flow chart showing a data transmission method according to an embodiment of the present invention. As shown in FIG. 3, the data transmission method includes the following steps: Step S302: The data sending end compresses the XML part of the Soap message and packages the compressed data as an attachment into the Soap message, and sends the packaged Soap message to the The data receiving end; Step S304, after receiving the Soap message, the data receiving end extracts the attachment of the Soa message, and decompresses the accessory to obtain the XML part. In the transmission method, step S302 includes: Step S302-2, the data sending end compresses the XML part in the Soap message to obtain binary data; Step S302-4, reassembles the compressed binary data as an attachment to the Soap message. And sending a Soap message to the data receiving end, where the data compression module identifies the compression method by using the attribute value of the content type field. Step S304 includes: Step S304-2: The data receiving end extracts the binary data in the received Soap message and the attribute value of the content type field; and in step S304-4, decompresses the binary data according to the attribute value. In the method, the attribute value is one of the following: lzw data corresponding to the lzw algorithm, 1ζ78 data corresponding to the 1ζ78 algorithm, and 1ζ77 data corresponding to the 1ζ77 algorithm. An example is as follows: An existing uncompressed Soap response packet is as follows: HTTP/1.1 200 ok

Server: Apache/1.3.29 (Unix)

Connection: close

Content-Type: text/xml

Content-length: 815

<?xml version="1.0" encoding="UTF-8" ?>

<SOAP-ENV: Envelope

Xmlns:xsi= ^M http://www. w3.org/2001/XMLSchema-instance" xmlns:xsd=http://www. w3.org/2001 XMLSchema

Xmlns:SOAP-ENV="http://schemas.xmIsoap.org/soap/envelope/"

Xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/ ^M >

<SOAP-ENV:Header>

<TransactionID

xmIns="http://w w.monternet.com/dsmp/schemas/ ^M >9571000000000002</Tra nsactionID>

</SOAP-ENV:Header>

<SOAP-ENV:Body>

</SOAP-ENV:Body> </SOAP-ENV:Envelope> The bold part is the XML data that needs to be transferred, and the block size is about 570 bytes. After the data is compressed using the LZW algorithm, a new data block is obtained. The new data block uses binary representation: 0x52 0x61 0x72 0x21 0x7B 0x00 0x40 0x07 0x00, with 250 bytes, compressed to the original 44%. Use Http to transfer this data block, and get the new data packet as follows:

HTTP/1.1 200 ok

Server: Apache/1.3.29 (Unix) Connection: close

Content-Type: lzwdata/xml content-length: 495 — MIME— boundary Content-Type: soapdata

Content-ID:

0x52 0x61 0x72 0x21 0x7B 0x00 0x40 0x07 0x00

— MIME— boundary— The bold part of the above packet, 1 , the description of Content-Type is modified to lzwdata/xml, indicating that the following data is compressed using the lzw algorithm, and the format after decompression is xml statement; The thicker part is the compressed binary data. MIME_boundary indicates that the data is an attachment to the Soap message. After receiving the data, the receiving end uses the lzw algorithm to decompress the subsequent binary data according to the description of the Content-Type to obtain the ml data in the normal UTF-8 format. Then use the SAX or DOM method to parse and get the data you need. If a request occurs or the response is unpacked by the Http protocol, the data in each packet can be compressed separately. According to the compression algorithm that is currently used, the value of Content-Type can be extended to: lzwdata/xml, lz77data/xmL lz78data/xml, etc. In summary, the implementation code of the algorithm (lzw, 1ζ77, 1ζ78) of the present invention is ready-made and convenient to implement; the compression ratio is particularly large, compared with the compression algorithm of the same type proposed by various researchers, the compression of this implementation mode The effect is the best. As you can see from the example, the xml data is compressed to 44%, and the whole package is reduced by 320 bytes. The scalability is strong, and a new data compression algorithm appears in the future; t卩 can be directly applied. The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A data transmission system, comprising:

a data sending device, configured to compress the XML portion in the Soap message and package the compressed data as an accessory into the Soap message, and send the packaged Soap message to the data receiving device;

The data receiving apparatus is configured to: after receiving the Soap message, extract an attachment of the Soap message, and decompress the accessory to obtain the XML part.

2. The data transmission system according to claim 1, wherein the data transmitting device comprises:

a data compression module, configured to compress the XML portion of the Soap message to obtain binary data;

a first data reassembly module, configured to reassemble the compressed binary data into the Soap message as an attachment, and send the Soap message to the data receiving apparatus, where the data compression module passes an attribute of a content type field The value identifies the compression method.

3. The data transmission system according to claim 2, wherein the data receiving device comprises:

a second data reassembly module, configured to extract binary data in the received Soap message and attribute values of the content type field;

And a data decompression module, configured to decompress the binary data according to the attribute value.

The data transmission system according to any one of claims 1 to 3, wherein the attribute value is one of: lzw data corresponding to the lzw algorithm, 1ζ78 data corresponding to the 1ζ78 algorithm, corresponding to 1ζ77 algorithm of 1ζ77 data.

The data transmission system according to any one of claims 1 to 3, wherein the attribute value is one of: lzw data/XML, 1ζ78 data/XML, 1ζ77 data/XML.

6. A data transmission method, comprising the steps of:

Step 1: The data sending end compresses the XML part in the Soap message and packages the compressed data as an accessory into the Soap message, and sends the packaged Soap message to the data receiving end;

Step 2: After receiving the Soap message, the data receiving end extracts an attachment of the Soap message, and decompresses the accessory to obtain the XML part.

7. The data transmission method according to claim 6, wherein the step one comprises:

Step a, the data sending end compresses the XML part in the Soap message to obtain binary data;

In step b, the compressed binary data is reassembled into the Soap message as an attachment, and the Soap message is sent to the data receiving end, where the data compression module identifies the compression method by using the attribute value of the content type field.

The data transmission method according to claim 7, wherein the step 2 includes: Step a, the data receiving end extracts binary data in the received Soap message and attribute values of the content type field ; as well as

Step b: Decompress the binary data according to the attribute value.

The data transmission method according to any one of claims 6 to 8, wherein the attribute value is one of: lzw data corresponding to the lzw algorithm, 1ζ78 data corresponding to the 1ζ78 algorithm, corresponding to 1ζ77 algorithm of 1ζ77 data.

The data transmission method according to any one of claims 6 to 8, characterized in that the attribute value is one of the following: 】zw data XML, 1ζ78 data/XML, 〖z77 data/XML.