2.1 Transport
This protocol consists of a set of RESTful (representational state transfer) web services, and HTTPS over TCP/IP, as specified in [RFC2616]. All client messages to the server MUST use HTTPS.
Protocol messages MUST be formatted as specified either in XML or in JSON. Protocol server faults MUST be returned by using HTTP status codes as specified in [RFC2616], section 10, Status Code Definitions.