CN107231347B - Method and system for data stream transmission service - Google Patents

Abstract

The invention relates to a method and system for data stream transmission service. First, define the format of the service data flow: SDS type + SDS corresponding service primitive + SDS parameter; then, according to the service request service primitive, encode the service parameters into the service data flow; finally, the receiving end receives the service data flow, needs Decode the service data stream to obtain service parameters. The present invention invents a concretely implementable method and system for the data stream interaction method described in the "Universal Service Agreement" standard, and solves the problem that the standard does not specifically solve the problem of data stream transmission services mentioned in the standard; the present invention It can also solve problems that require multiple complex data for overall interaction or expression.

Description

Method and system for data stream transmission service

technical field

The invention belongs to the technical field of electric power automation, and relates to information interaction occasions where both parties need to exchange complex data, such as information interaction of a service-oriented (SOA) architecture system, and specifically a method and system for data stream transmission services.

Background technique

With the development of computer and network technology, the intelligence level and requirements of the power grid are constantly improving. The traditional communication protocols and information interaction mechanisms designed for some specific applications in the power system can no longer meet the needs. It is necessary to continue to make these protocols The non-standard expansion leads to the non-interoperability of the system. The information interaction mechanism of the service-oriented (SOA) architecture system has become a development direction. For this reason, my country has issued the "Power System Simple Service Interface Specification" (DL/T1233) for this development. The foundation has been laid, and the "General Service Agreement for Power System" standard to be released has proposed a solution to this problem. However, the "General Service Agreement for Power System" has no specific solution for service transmission through data streams. The invention proposes a solution to the problem of how to realize service transmission through data flow on the basis of "General Service Agreement for Electric Power System".

Contents of the invention

The purpose of the present invention is to provide a data stream transmission service method and system that solves the problem that the "Universal Service Agreement" standard does not specifically solve the problem of the data stream transmission service mentioned in the standard.

In order to achieve the above object, the technical solution of the present invention is: a method for data stream transmission service, comprising the following steps,

S1. Define the format of the service data stream: SDS type + SDS corresponding service primitive + SDS parameter;

S2. Encode the service parameters into a service data stream according to the service request service primitive, that is, firstly, determine the type of service data stream to be formed; then, obtain the service request service primitive corresponding to the service data stream type; and then, Assign the SDS type according to the type of service data flow to be formed; then, write the service name of the service request service primitive into the corresponding service primitive of the SDS; finally, according to the type and order of the service request parameters in the service request service primitive , query the service parameter encoding table, and according to the found encoding method, encode the corresponding service request parameter and write it into the SDS parameter to form a service data stream;

S3. After receiving the service data stream, the receiving end needs to decode the service data stream to obtain service parameters, namely: firstly, parse the first byte of the service data stream to obtain the SDS type of the service data stream; then, parse the service according to the STRING type format Data flow, obtain the service name of the service request service primitive, and then obtain the service request service primitive; finally, analyze the service data flow according to the SDS type and service request service primitive, and obtain the corresponding service parameters.

In an embodiment of the present invention, the service parameter coding table includes a basic parameter type coding table and a combined parameter type coding table, wherein the basic parameter type coding table consists of the basic parameter type, the coding method corresponding to the basic parameter type, and the accounting data The number of bytes of the stream; the combination parameter type encoding table is composed of the combination parameter type, the encoding method corresponding to the combination parameter type, and the number of bytes occupying the data stream.

In one embodiment of the present invention, the length of the SDS type is one byte; the length of the SDS corresponding service primitive is variable, and its format is a STRING type; the SDS parameter includes multiple segments, and the number of segments is determined by the service request primitive The number of parameters in is determined, and the format of each segment is determined by the type of each parameter in the service request service primitive.

In an embodiment of the present invention, the value of the SDS type includes I, D, O, wherein, I represents an IN parameter, which is the direction from the client to the server; O represents an OUT parameter, which is the direction from the server to the client; D Indicates a data block without IN and OUT parameters.

In an embodiment of the present invention, the number of segments of the SDS parameter is determined in the following manner:

If the value of the SDS type is 1, the number of segments of the SDS parameter is the number of parameters identified as IN in the service request service primitive;

If the value of the SDS type is 0, the number of segments of the SDS parameter is the number of parameters marked as OUT in the service request service primitive;

If the value of the SDS type is D, the number of segments of the SDS parameter is the number of all parameters in the service primitive of the service request.

In an embodiment of the present invention, in the step S2, if the client sends a service request to the server, that is, when the service request data stream needs to be formed, the specific method of encoding the service parameters into the service data stream is as follows:

1) Obtain the corresponding service request service primitive of the service request data flow;

2) Assign the SDS type as I;

3) Write the service name of the service request service primitive into the corresponding service primitive of SDS in the format of STRING type;

4) Query the service parameter encoding table, and write the corresponding parameters marked as IN in the service request service primitive into the SDS parameters in turn, until all the parameters marked as IN are written into the SDS parameters.

In an embodiment of the present invention, in the step S2, if the server sends a service response to the client, that is, when it is necessary to form a service response data stream, the specific method of encoding the service parameters into a service data stream is as follows:

1) Obtain the corresponding service request service primitive of the service response data flow;

2) Assign the SDS type to O;

3) Write the service name of the service request service primitive into the corresponding service primitive of SDS in the format of STRING type;

4) Query the service parameter encoding table, and write the corresponding parameters marked as OUT in the service request service primitive into the SDS parameters in turn, until all the parameters marked as OUT are written into the SDS parameters.

In an embodiment of the present invention, in the step S2, if complex data transmission needs to be formed, the specific method of encoding the service parameters into a service data stream is as follows:

1) Obtain the corresponding service request service primitive of the service response data stream;

2) Assign the SDS type to D;

3) Write the service name of the service request service primitive into the corresponding service primitive of SDS in the format of STRING type;

4) Query the service parameter encoding table, and write the parameters in the service primitive of the service request into the SDS parameter in turn.

The present invention also provides a data stream transmission service system, including:

The service data flow definition unit is used to define the format of the service data flow, the format of the service data flow: SDS type + SDS corresponding service primitive + SDS parameter;

The service parameter encoding unit encodes the service parameters into a service data stream according to the service request service primitive and the service data stream format defined by the service data stream definition unit, specifically: first, judge the type of service data stream to be formed; then, Obtain the service request service primitive corresponding to the service data flow type; then, assign a value to the SDS type according to the service data flow type to be formed; then, write the service name of the service request service primitive into the corresponding service primitive of the SDS ;Finally, query the service parameter code table, write the corresponding parameters in the service parameter code table into the SDS parameter according to the service request service primitive and SDS type, and form the service data flow;

The service data flow decoding unit decodes the service data flow to obtain service parameters, specifically: first, parses the first byte of the service data flow to obtain the SDS type of the service data flow; then parses the service data flow according to the STRING type format to obtain The service name of the service request service primitive, and then obtain the service request service primitive; finally, analyze the service data flow according to the SDS type and the service request service primitive, and obtain the corresponding service parameters.

In one embodiment of the present invention, the length of the SDS type is one byte; the length of the SDS corresponding service primitive is variable, and its format is a STRING type; the SDS parameter includes multiple segments, and the number of segments is determined by the service request primitive The number of parameters in is determined, and the format of each segment is determined by the type of each parameter in the service request service primitive.

In an embodiment of the present invention, the value of the SDS type includes I, D, O, wherein, I represents an IN parameter, which is the direction from the client to the server; O represents an OUT parameter, which is the direction from the server to the client; D Indicates a data block without IN and OUT parameter identification; the number of segments of the SDS parameter is determined by the following method:

If the value of the SDS type is 1, the number of segments of the SDS parameter is the number of parameters identified as IN in the service request service primitive;

If the value of the SDS type is 0, the number of segments of the SDS parameter is the number of parameters marked as OUT in the service request service primitive;

If the value of the SDS type is D, the number of segments of the SDS parameter is the number of all parameters in the service primitive of the service request.

Compared with the prior art, the present invention has the following beneficial effects: the present invention invents a concretely implementable method for the data stream interaction method described in the standard "General Service Agreement for Electric Power Systems", and solves the problem that the standard does not specifically address the standard The problem of transmitting services through data streams mentioned in the above; the present invention can also solve the problem of requiring multiple complex data for overall interaction or expression.

Description of drawings

FIG. 1 is a schematic diagram of the method for converting service description primitives to SDS in the present invention.

Detailed ways

The technical solution of the present invention will be specifically described below in conjunction with the accompanying drawings.

As shown in FIG. 1, a method for forming a data stream for a transmission service according to the present invention includes the following steps,

S1. Define the format of the service data flow: SDS type + SDS corresponding service primitive + SDS parameter, wherein, the length of the SDS type is one byte; the length of the SDS corresponding service primitive is variable, and its format is STRING type; SDS parameter Contains multiple segments, the number of segments is determined by the number of parameters in the service request service primitive, and the format of each segment is determined by the type of each parameter in the service request service primitive.

S2. According to the service primitive of the service request, encode the service parameters into the service data flow, namely: firstly, judge the type of the service data flow to be formed; then, obtain the service request primitive corresponding to the type of the service data flow (service request service Primitives are stored in the service management center, and the sender and receiver can call the corresponding service request service primitives through the service management center); then, assign the SDS type according to the type of service data flow to be formed; then, the The service name of the service request service primitive is written into the corresponding service primitive of the SDS; finally, according to the type and order of the service request parameters in the service request service primitive, query the service parameter coding table, and according to the found coding method, put The corresponding service request parameters are encoded and written into the SDS parameters to form a service data stream;

S3. After receiving the service data stream, the receiving end needs to decode the service data stream to obtain service parameters, namely: firstly, parse the first byte of the service data stream to obtain the SDS type of the service data stream; then, parse the service according to the STRING type format Data flow, obtain the service name of the service request service primitive, and then obtain the service request service primitive; finally, analyze the service data flow according to the SDS type and service request service primitive, and obtain the corresponding service parameters.

In the above process, in the case where the communication parties adopt the pre-agreed transmission type and service request service primitive, the data flow can simplify the part of "SDS type + SDS corresponding service primitive" and use the pure "SDS parameter" form to transmit the service; that is It is equivalent to considering "SDS type + SDS corresponding service primitive" as known;

In an embodiment of the present invention, the service parameter coding table includes a basic parameter type coding table and a combined parameter type coding table, wherein the basic parameter type coding table consists of the basic parameter type, the coding method corresponding to the basic parameter type, and the accounting data The number of bytes of the stream; the combined parameter type encoding table is composed of the combined parameter type, the encoding method corresponding to the combined parameter type, and the number of bytes in the data stream; the combined parameter type is the parameter type that does not belong to the basic parameter type (specifically Table examples can be found in Table 2 and Table 3, among which, Table 2 is the basic parameter type coding table, and Table 3 is the combination parameter type coding table).

The value of the SDS type includes I, D, O, wherein, I represents the IN parameter, which is the direction from the client to the server; O represents the OUT parameter, which is the direction from the server to the client; D represents no IN, OUT parameter identification Data block; the number of segments of the SDS parameter is determined in the following manner:

If the value of the SDS type is 1, the number of segments of the SDS parameter is the number of parameters identified as IN in the service request service primitive;

If the value of the SDS type is 0, the number of segments of the SDS parameter is the number of parameters marked as OUT in the service request service primitive;

If the value of the SDS type is D, the number of segments of the SDS parameter is the number of all parameters in the service primitive of the service request.

In the step S2, if the client sends a service request to the server, that is, when the service request data stream needs to be formed, the specific method of encoding the service parameters into the service data stream is as follows:

1) Obtain the corresponding service request service primitive of the service request data stream;

2) Assign the SDS type as I;

3) Write the service name of the service request service primitive into the corresponding service primitive of SDS in the format of STRING type;

4) Write the corresponding parameters marked as IN in the service request service primitive into the SDS parameters in turn, until all the parameters marked as IN are written into the SDS parameters.

In the step S2, if the server sends a service response to the client, that is, when the service response data stream needs to be formed, the specific method of encoding the service parameters into the service data stream is as follows:

1) Obtain the corresponding service request service primitive of the service response data stream;

2) Assign the SDS type to O;

3) Write the service name of the service request service primitive into the corresponding service primitive of SDS in the format of STRING type;

4) Write the corresponding parameters marked as OUT in the service request service primitive into the SDS parameters in turn until all the parameters marked as OUT are written into the SDS parameters.

In the step S2, if complex data transmission needs to be formed, the specific method of encoding the service parameters into a service data stream is as follows:

1) Obtain the corresponding service request service primitive of the service response data flow;

2) Assign the SDS type to D;

3) Write the service name of the service request service primitive into the corresponding service primitive of SDS in the format of STRING type;

4) Write the parameters in the service primitives of the service request into the SDS parameters in turn.

The present invention also provides a data stream transmission service system, including:

The service data flow definition unit is used to define the format of the service data flow, the format of the service data flow: SDS type + SDS corresponding service primitive + SDS parameter;

The service parameter encoding unit encodes the service parameters into a service data stream according to the service request service primitive and the service data stream format defined by the service data stream definition unit, specifically: first, judge the type of service data stream to be formed; then, Obtain the service request service primitive corresponding to the service data flow type; then, assign a value to the SDS type according to the service data flow type to be formed; then, write the service name of the service request service primitive into the corresponding service primitive of the SDS ;Finally, query the service parameter code table, write the corresponding parameters in the service parameter code table into the SDS parameter according to the service request service primitive and SDS type, and form the service data flow;

The service data flow decoding unit decodes the service data flow to obtain service parameters, specifically: first, parses the first byte of the service data flow to obtain the SDS type of the service data flow; then parses the service data flow according to the STRING type format to obtain The service name of the service request service primitive; finally, analyze the service data flow according to the SDS type assignment to obtain the corresponding parameters.

The length of the SDS type is one byte; the length of the corresponding service primitive of the SDS is variable, and its format is a STRING type; the SDS parameter includes multiple segments, and the number of segments is determined by the number of parameters in the service request primitive, each The format of the segment is determined by the type of each parameter in the service request service primitive.

The value of the SDS type includes I, D, O, wherein, I represents the IN parameter, which is the direction from the client to the server; O represents the OUT parameter, which is the direction from the server to the client; D represents no IN, OUT parameter identification Data block; the number of segments of the SDS parameter is determined in the following manner:

If the value of the SDS type is 1, the number of segments of the SDS parameter is the number of parameters identified as IN in the service request service primitive;

If the value of the SDS type is 0, the number of segments of the SDS parameter is the number of parameters marked as OUT in the service request service primitive;

If the value of the SDS type is D, the number of segments of the SDS parameter is the number of all parameters in the service primitive of the service request.

The solutions of the present invention are described in detail below.

The invention proposes a method for converting the abstract service interface primitive described in DL/T 1233 ("Power System Simple Service Interface Specification") (abbreviation: S language) to a data stream. The content of the invention includes the service data stream (Service DataStream, referred to as SDS) format and the method of encoding parameters to form SDS according to the service S language primitive. Solve the problem that the "General Service Agreement for Electric Power System" does not specifically address the transmission of services through data streams mentioned in the standard.

1) Service Data Stream (SDS) format

The SDS format is shown in Table 1, and the details are as follows:

Table 1 Service Data Stream (SDS) format

S ServiceName Par-1 Par-2 ... Par-n

(1) SDS type: S segment, the length is one byte ASCII code, the meaning is as follows:

a) S="I": Indicates the IN parameter, which is the direction from the client to the server;

b) S="O": indicates the OUT parameter, which is the direction from the server to the client;

c) S="D": indicates a data block without IN and OUT parameter identification;

d) S can also be other values for extended use.

(2) SDS corresponding service primitive: ServiceName segment, variable length, its format is the same as STRING type parameter;

(3) SDS parameters: Par-1 to Par-n segments, the number of segments and the format of each segment depend on the number and type of parameters described in the corresponding S language:

a) When S=I, the number of parameter segments is the number of parameters identified as IN in the service description;

b) When S=O, the number of parameter segments is the number of parameters identified as OUT in the service description;

c) When S=D, the number of parameter segments is the number of all parameters in the service description;

2) According to the service description primitive, the method of encoding service parameters to form SDS

(Figure 1) is a schematic diagram of the conversion method for forming SDS based on service description primitives, the method is as follows:

A. When the client sends a service request to the server, it needs to form a service request data stream. The encoding method is as follows:

(1) Obtain the corresponding service request service primitive;

(2) Assign the data stream type S (data stream head byte) to "I" (① in Figure 1);

(3) Compile the service name of the service request primitive into the data stream according to (Table 2) STRING type format (② in Figure 1);

(4) In turn, encode the corresponding parameters marked as IN in the service primitives into the data stream according to the coding formats (Table 2) and (Table 3), until all the parameters marked as IN are compiled into the data stream (Figure 1 ③);

The data flow formed by (1)-(3) above is the service request data flow.

B. When the server sends a service response to the client, it needs to form a service response data stream. The encoding method is as follows:

(1) Obtain the corresponding service request service primitive;

(2) Assign the data stream type S (data stream head byte) to "O" (④ in Figure 1);

(3) Compile the service name of the service request primitive into the data stream according to (Table 2) STRING type format (⑤ in Figure 1);

(4) In turn, encode the corresponding parameters marked as OUT in the service primitives into the data stream according to the coding formats (Table 2) and (Table 3), until all the parameters marked as OUT are compiled into the data stream (Figure 1 ⑥);

The data flow formed by the above (1)-(3) is the service response data flow.

C. When the data stream is used as complex data transmission, the encoding method is similar, except that the data stream type is "D", and the IN or OUT flag is not judged during encoding (usually there is no IN and OUT in the primitive).

3) According to the service description primitive, the method of decoding the SDS and obtaining the parameters

After the receiving end receives the data stream, the decoding process of obtaining parameters from the data stream is as follows:

(1) Analyze the first byte of the data stream to obtain the data stream type;

(2) Parse the data stream according to the STRING type format to obtain the service primitive name;

(3) Obtain the corresponding service request service primitive;

(4) According to the data stream type, analyze the data stream according to the corresponding identification in the service primitive ("I" corresponds to IN parameters, "O" corresponds to OUT parameters) parameter types and order, and obtain corresponding parameters.

4) Data format of the parameter section

The data format of the parameter segment is also the encoding format of each parameter, which is described in the form of an encoding library. The encoding library contains encoding methods for all service parameters described by S, which are divided into basic parameter types and special (combined) parameter types in terms of types.

a) Basic parameter type

The basic parameter types to be supported, the corresponding encoding methods, and the number of bytes in the data stream (Table 2) (refer to the GSP basic data type definition, which can be expanded as needed):

(Table 2) Basic parameter type coding table

b) special (composite) parameter types

Supported special (combined) parameter types, corresponding encoding methods, and the number of bytes in the data stream (Table 3) (can be expanded as needed):

(Table 3) Special (combined) parameter type encoding table

5) Expansion of S language

S language (DLT 1233 can only describe simple parameter descriptions, and cannot meet the needs of describing special (combined) parameter types. The expansion is as follows:

1. Use IN to represent the service request input parameters (parameters from the client to the server);

2. Use OUT to indicate the service response return parameters (parameters from the server to the client);

3. Add special parameter types;

4. Structural data type;

5. Add array and structure array parameters.

Example 1: Service primitive with special parameter types

< GetSubstationChIEDSCDFile ( // service name

IN STRING: IEDName, //IED name

OUT STRING: fileName, //file name

OUT FILEDATA: fileDate, //IED SCD file content, special parameter type

)" Get the SCD file of the changed IED"/>

Example 2: Service Primitive with Array of Augmented Structures

< GetSubstationIEDlist ( // service name

IN STRING: SubstationName, //substation name

OUT int16:IEDnumber, //IED number

OUT struct IEDlist{ STRING:IEDname, STRING:IEDdesc}[], //IED list, structure array

)" Get IED list"/>

Example 3: Primitives used as complex data representations

<authPara(//Authentication parameters

STRING Identity, //Identity

INT8U signType, //signature type

TIME currentTime, //current time

STRING signValue, //signature value

)"Authentication Parameters"/>.

The specific application of technical scheme of the present invention is as follows:

(1) Combining with the "Universal Service Agreement" to realize the transmission of application services under the service-oriented architecture;

(2) For encryption and security authentication, multiple data or parameters are encoded into a data stream through SDS, so as to encrypt and digitally sign multiple data at one time;

(3) As an information frame format, embed existing application communication protocols to realize data transmission beyond the provisions of the transmission protocol, such as embedding SDS into DL/T634.5104 and DL/T 476 communication protocols.

Those skilled in the art should understand that the embodiments of the present application may be provided as methods, systems, or computer program products. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present application is described with reference to flowcharts and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present application. It should be understood that each procedure and/or block in the flowchart and/or block diagram, and a combination of procedures and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor, or processor of other programmable data processing equipment to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing equipment produce a Means for realizing the functions specified in one or more steps of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a specific manner, such that the instructions stored in the computer-readable memory produce an article of manufacture comprising instruction means, the instructions The device realizes the function specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby The instructions provide steps for implementing the functions specified in the flow chart flow or flows and/or block diagram block or blocks.

The above are the preferred embodiments of the present invention, and all changes made according to the technical solution of the present invention, when the functional effect produced does not exceed the scope of the technical solution of the present invention, all belong to the protection scope of the present invention.

Claims (10)

1. a kind of method of data streaming services, it is characterised in that: include the following steps,

S1, the format for defining server data stream SDS: SDS type+SDS corresponding with service primitive+SDS parameter；

S2, foundation service request service primitive, are encoded into server data stream for service parameter, it may be assumed that first, it is determined that the clothes that need to be formed Business data stream type；Then, service request service primitive corresponding with service data stream type is obtained；And, to be formed again according to needing Service data stream type to SDS type carry out assignment；Then, the Service name write-in SDS of service request service primitive is corresponding In service primitive；Finally, type and sequence according to service request parameter in service request service primitive, query service parameter is compiled Code table, and according to the coding method found, it is written in SDS parameter, is formed after corresponding service request parameter is encoded Server data stream；

S3, receiving end receive server data stream, need to decode server data stream, to obtain service parameter, it may be assumed that firstly, parsing clothes Business data flow first byte, obtains the SDS type of server data stream；Then, it by STRING type format analysis service data flow, obtains The Service name of service request service primitive is taken, and then obtains service request service primitive；Finally, according to SDS type, service request Service primitive parses server data stream, obtains corresponding service parameter.

2. according to the method described in claim 1, it is characterized by: the service parameter coding schedule includes that basic parameter type is compiled Code table and combination parameter type coding table, wherein basic parameter type coding table is by basic parameter type, the basic parameter type Corresponding coding method and the byte number for accounting for data flow are constituted；Combination parameter type coding table is by combination parameter type, the group It closes the corresponding coding method of parameter type and accounts for the byte number composition of data flow.

3. according to the method described in claim 1, it is characterized by: the length of the SDS type is a byte；SDS is corresponding The length of service primitive is variable, and format is STRING type；SDS parameter includes multistage, and the number of section is by service request service The number of parameter determines in primitive, and each section of format is determined by the type of parameters in service request service primitive.

4. according to the method described in claim 2, it is characterized by: the SDS type value includes I, D, O, wherein I is indicated IN parameter, for client to service extreme direction；O indicate OUT parameter, be server-side to client-side to；D indicates no IN, OUT ginseng The data block of number mark；The number of the section of the SDS parameter determines in the following way:

If SDS type value is I, the number of the section of SDS parameter is that the parameter of IN is identified as in service request service primitive Number；

If SDS type value is O, the number of the section of SDS parameter is that the parameter of OUT is identified as in service request service primitive Number；

If SDS type value is D, the number of the section of SDS parameter is the number of all parameters in service request service primitive.

5. according to the method described in claim 3, it is characterized by: being serviced in the step S2 if client is sent out to server-side When request, i.e., when need to form service data stream, the concrete mode that service parameter is encoded into server data stream is as follows:

1) the corresponding service request service primitive of service data stream is obtained；

It 2) is I by SDS type assignment；

3) by the Service name of service request service primitive, by STRING type format write-in SDS corresponding with service primitive；

4) query service parameter coding table will successively be identified as the correspondence parameter of IN, write-in SDS ginseng in service request service primitive In number, until in all parameters for being identified as IN all write-in SDS parameter.

6. according to the method described in claim 3, it is characterized by: being serviced in the step S2 if server-side is sent out to client When response, i.e., when need to form service response data flow, the concrete mode that service parameter is encoded into server data stream is as follows:

1) the corresponding service request service primitive of service response data flow is obtained；

It 2) is O by SDS type assignment；

3) by the Service name of service request service primitive, by STRING type format write-in SDS corresponding with service primitive；

4) query service parameter coding table will successively be identified as the correspondence parameter of OUT in service request service primitive, SDS is written In parameter, until in all parameters for being identified as OUT all write-in SDS parameter.

7. according to the method described in claim 3, it is characterized by: in the step S2, if need to form complex data transmission makes Used time, the concrete mode that service parameter is encoded into server data stream are as follows:

1) the corresponding service request service primitive of service response data flow is obtained；

It 2) is D by SDS type assignment；

3) by the Service name of service request service primitive, by STRING type format write-in SDS corresponding with service primitive；

4) query service parameter coding table is written in SDS parameter successively by parameter in service request service primitive.

8. a kind of system of data streaming services, it is characterised in that: include:

Server data stream definition unit, for defining the format of server data stream, the format of server data stream SDS: SDS type+ SDS corresponding with service primitive+SDS parameter；

Service parameter coding unit, according to service number defined in service request service primitive and server data stream definition unit According to stream format, service parameter is encoded into server data stream, specifically i.e.: first, it is determined that the service data stream type that need to be formed；And Afterwards, service request service primitive corresponding with service data stream type is obtained；Again and, according to the service data stream type that need to be formed Assignment is carried out to SDS type；It then, will be in the Service name write-in SDS corresponding with service primitive of service request service primitive；Finally, Query service parameter coding table writes parameter corresponding in service parameter coding schedule according to service request service primitive, SDS type Enter in SDS parameter, forms server data stream；

Server data stream decoding unit, server data stream is decoded, to obtain service parameter, specifically i.e.: firstly, analysis service number According to stream first byte, the SDS type of server data stream is obtained；Then, by STRING type format analysis service data flow, clothes are obtained The Service name of business request service primitive, and then obtain service request service primitive；Finally, according to SDS type, service request service Primitive parses server data stream, obtains corresponding service parameter.

9. system according to claim 8, it is characterised in that: the length of the SDS type is a byte；SDS is corresponding The length of service primitive is variable, and format is STRING type；SDS parameter includes multistage, and the number of section is by service request service The number of parameter determines in primitive, and each section of format is determined by the type of parameters in service request service primitive.

10. system according to claim 9, it is characterised in that: the SDS type value includes I, D, O, wherein I is indicated IN parameter, for client to service extreme direction；O indicate OUT parameter, be server-side to client-side to；D indicates no IN, OUT ginseng The data block of number mark；The number of the section of the SDS parameter determines in the following way:

If SDS type value is I, the number of the section of SDS parameter is that the parameter of IN is identified as in service request service primitive Number；

If SDS type value is O, the number of the section of SDS parameter is that the parameter of OUT is identified as in service request service primitive Number；

If SDS type value is D, the number of the section of SDS parameter is the number of all parameters in service request service primitive.