SOAP is a platform- and language-independent protocol based on XML and used to send messages and data between applications. SOAP defines the structure of messages, describes how messages are to be processed, and provides rules for encoding application-defined datatypes. SOAP allows applications to send and receive remote procedure calls using any standard transport-layer protocol, usually HTTP.
A SOAP message consists of a header and a body, both of which are contained in a SOAP envelope:
Figure 1-1: SOAP message structure
The following is an example of SOAP request message for a select statement.
Figure 1-2: SOAP request message
The request message contains no header information. The following is a SOAP response message corresponding to the previous request message. This message contains a header. The body of the message is not shown.
Figure 1-3: SOAP response message
For more detailed information on SOAP, refer to the following documents:
Simple Object Access Protocol (1.1) http://www.w3.org/TR/SOAP/
Simple Object Access Protocol (1.2) Part 1: http://www.w3.org/TR/soap12-part1/
Simple Object Access Protocol (1.2) Part 2: http://www.w3.org/TR/soap12-part2/
