Summary

This Recommendation defines the procedures for use of more than one video channel in H.320‑based systems, and for labelling individual channels with a "role", which indicates requirements for processing the channel and the role of the channel content in the call.  Role labels are applicable to both H.320 and H.245 signalling-based systems.  The defined procedures include control, indication, and capability exchange mechanisms

This 2005 revision is corrected, including corrections formerly contained in the H.239 (2003) Implementor's Guide.