Summary

This Recommendation covers the technical requirements for narrow-band visual telephone services defined in H.200 and F.720-series Recommendations, in those situations where the transmission path includes one or more packet-based networks, each of which is configured and managed to provide a non-guaranteed Quality of Service (QoS) which is not equivalent to that of N-ISDN, such that additional protection or recovery mechanisms beyond those mandated by ITU-T Rec. H.320 need be provided in the terminals. It is noted that ITU-T Rec. H.322 addresses the use of some other LANs which are able to provide the underlying performance not assumed by the ITU-T Recs H.323 and H.225.0.

This Recommendation describes how audio, video, data, and control information on a packet-based network can be managed to provide conversational services in H.323 equipment.

Products claiming compliance with Version 7 of H.225.0 (this version) shall comply with all of the mandatory requirements of this Recommendation. Version 7 products can be identified by H.225.0 messages containing a protocolIdentifier value of {itu-t (0) recommendation (0) h (8) 2250 version (0) 7}.

This revision incorporates the following changes:

1)��������� Correction of defects identified in the H.323-Series Implementor's Guide which include:

a)�� Editing corrections.

b)�� Clarification to the length of information element, where "*" denotes an undefined maximum length.

b)�� Clarification to User-user information element in Setup acknowledge, Status and Status inquiry messages.

c)�� Addition of destinationInfo field to H.225.0 ReleaseComplete and Notify messages.

2)��������� Incorporation of multi-language caller and called party identification.

3)��������� Clarifications to the processing of H.225.0 Call Signalling messages errors in clause 7.1.