1.3.2 RDP Channels and Multitransport Connections

The main RDP connection is encapsulated in the Transmission Control Protocol (TCP) ([MS-RDPBCGR] section 2.1). The I/O channel ([MS-RDPBCGR] section and and the optional message channel ([MS-RDPBCGR] sections and are encapsulated within the main RDP connection and are used to transport core RDP PDUs, input and graphics data. In addition to these two channels there is a collection of negotiated static virtual channels ([MS-RDPBCGR] section 1.3.3). One of these static virtual channels, named "DRDYNVC", multiplexes a collection of dynamic virtual channels ([MS-RDPEDYC] sections 1, 2 and 3).

Multitransport connections run over a separate transport protocol to the main RDP connection and multiplex a collection of selected dynamic virtual channels.

The following figure illustrates the hierarchy and encapsulation of RDP channels and transports.

RDP channels and transport

Figure 2: RDP channels and transport