1.4 Relationship to Other Protocols

The Remote Desktop Protocol: Multitransport Extension operates over the RDP-UDP protocol, as defined in [MS-RDPEUDP] section 1, 2, and 3. Protocol traffic (section 2.2) is secured by using Transport Layer Security (TLS) ([RFC2246], [RFC4346] and [RFC5246]) for reliable RDP-UDP streams and Datagram Transport Layer Security (DTLS) ([RFC4347]) for unreliable (lossy) RDP-UDP streams. The TLS or DTLS handshake, as well as the encrypted payload, are embedded in the RDPUDP_SOURCE_PAYLOAD_HEADER as defined in [MS-RDPEUDP].

A multitransport connection is initiated by an RDP server sending the Initiate Multitransport Request PDU ([MS-RDPBCGR] section 2.2.1.15.1) to an RDP client over the main RDP connection.