3.1.5 Message Processing Events and Sequencing Rules
The expert MUST extract Port and IP Address information from the Remote Assistance Connection String (Section 2.2 of [MS-RAI]) to establish a TCP Connection. When more than one pair of Port and IP address exists, the expert MUST attempt connecting to all Port and IP Address pairs present in the Remote Assistance Connection String. The first successful TCP connection MUST be used for all further communication.
After a TCP connection is established, a Remote Desktop connection (described in Sections 3.2 of [MS-RDPBCGR]) MUST be initiated using Extensions to the Remote Desktop Protocol as defined in section 2.2.7.
Upon completion of the Remote Desktop Connection, depending on the negotiated Remote Assistance protocol version, the Remote Assistance session MUST be established as described in sections 3.3, 3.5, and 3.7.