What is SOAP ?

SOAP

• Simple Object Access Protocol
• SOAP is an XML-based protocol for exchanging information between computers.
  XML is used for data encoding ("text" based protocol vs. "binary" protocol)
• Main focus of SOAP is Remote Procedure Calls (RPC) transported via HTTP.
  Like XML-RPC; Supports XML-based RPC
• SOAP is platform independent, and therefore enables diverse applications to communicate with one another.

What does SOAP Define ?

• Message Envelope
• Encoding Rules
• RPC Convention
• Binding with underlying protocols

SOAP Message Envelope

• Encoding information
• Header (optional) : Could contain context knowledge
• Security
• Transaction
• Body : RPC methods and parameters, Contains application data

SOAP Encoding

• Rules of expressing application-defined data types in XML
• Simple values
  Built-in types from XML Schema, Part 2 (simple types, enumerations, arrays of bytes)
• Compound values (Structs, arrays, complex types)