The various components of SOAP protocol are,
1. SOAP Envelope
It is the root element in the SOAP message. It has an optional Header element and a mandatory Body element.
2. SOAP Header
It is an optional element which is used to pass the application specific information like Authentication information etc.
3. SOAP Body
It is the mandatory element which carries the data between the Client and the Server machines.
4. SOAP Fault
This is used to carry the Error information in the SOAP message