ITU-T Recommendations

Recommendation ITU T H.245 specifies syntax and semantics of terminal information messages as well as procedures to use them for in-band negotiation at the start of or during communication. The messages cover receiving and transmitting capabilities as well as mode preference from the receiving end, logical channel signalling, and Control & Indication. Acknowledged signalling procedures are specified to ensure reliable audiovisual and data communication.
Products claiming compliance with Version 17 of Recommendation ITU T H.245 shall comply with all of the mandatory requirements of this Recommendation. Version 17 products can be identified by Recommendation ITU T H.245 TerminalCapabilitySet messages containing a protocolIdentifier value of {ITU T (0) recommendation (0) h (8) 245 version (0) 17}.
Relative to Recommendation ITU T H.245 Version 16 (2011), this version incorporates the following changes:
– Add procedures in Annex V to support better interoperability between IPv4 and IPv6 devices.
– Updated Table VIII.1 to support the revisions made to Recommendation ITU T H.241.
– Support of an SCTP media transport in H.323 systems, including the addition of Annex U.
– Support of DTLS media transport in H.323 systems, including the addition of Annex U.
– Support of out of band data channel establishment for Annex U.
– Propose updates to Recommendation ITU T H.245 to support SCTP: split dtls-sctp into udp dtls-sctp and tcp-dtls-sctp.
– Add ExtendedAudioCapability and ExtendedDataCapability in Recommendation ITU T H.245.