2.1 Transport

This protocol consists of a series of XML elements contained in request or response messages between a client and server. The encoded XML block containing the command and parameter elements is transmitted in either the request body of a request, or in the response body of a response. The request body and request response are always preceded by the HTTP header, as specified in [MS-ASHTTP], except for the Autodiscover command<1>.

All command messages are encoded as WBXML, except for the Autodiscover command, which uses plain XML. For more details about WBXML, see [MS-ASWBXML].