SOAP 1.1 and 1.2

SOAP is a lightweight, XML-based, protocol for exchange of information in a decentralized, distributed environment.

The protocol consists of three parts:

An envelope that defines a framework for describing what is in a message and how to process it.
A set of encoding rules for expressing instances of application-defined data types.
A convention for representing remote procedure calls and responses.

SOAP can be used with other protocols, such as HTTP.

The specifications for SOAP are published by the World Wide Web Consortium (W3C). The specification for SOAP 1.1 is described as a note at Simple Object Access Protocol 1.1. This specification has not been endorsed by the W3C, but forms the basis for the SOAP 1.2 specification.

SOAP 1.2 is a W3C recommendation and is published in two parts:

The specification also includes a primer that is intended to provide a tutorial on the features of the SOAP Version 1.2 specification, including usage scenarios. The primer is published at SOAP 1.2 Primer.