Page iii
Decided H.323, 28 May 1996
9/21/98 23:27 iii
Table of Contents
SUMMARY ...........................................................................................................................ii
1 SCOPE ..............................................................................................................................1
2 NORMATIVE REFERENCES............................................................................................2
3 DEFINITIONS....................................................................................................................4
4 SYMBOLS AND ABBREVIATIONS..................................................................................8
5 CONVENTIONS ................................................................................................................9
6 SYSTEM DESCRIPTION.................................................................................................10
6.1 Information Streams........................................................................................................................................10
6.2 Terminal Characteristics ................................................................................................................................10
6.2.1 Terminal elements outside the scope of H.323.............................................................................................11
6.2.2 Terminal elements within the scope of H.323..............................................................................................12
6.2.3 LAN Interface.............................................................................................................................................12
6.2.4 Video Codec ...............................................................................................................................................12
6.2.4.1 Terminal Based Continuous Presence...................................................................................................13
6.2.5 Audio Codec...............................................................................................................................................13
6.2.5.1 Audio Mixing ......................................................................................................................................14
6.2.5.2 Maximum Audio-Video Transmit Skew...............................................................................................14
6.2.6 Receive Path Delay .....................................................................................................................................14
6.2.7 Data Channel..............................................................................................................................................14
6.2.7.1 T.120 Data Channels ...........................................................................................................................15
6.2.8 H.245 Control Function ..............................................................................................................................16
6.2.8.1 Capabilities exchange ..........................................................................................................................17
6.2.8.2 Logical channel signalling ...................................................................................................................18
6.2.8.3 Mode preferences.................................................................................................................................19
6.2.8.4 Master Slave Determination.................................................................................................................19
6.2.8.5 Timer and counter values.....................................................................................................................20
6.2.9 RAS Signalling Function............................................................................................................................20
6.2.10 Call Signalling Function...........................................................................................................................21
6.2.11 H.225.0 Layer...........................................................................................................................................21
6.2.11.1 Logical channel numbers ...................................................................................................................21
6.2.11.2 Logical Channel Bitrate Limits ..........................................................................................................21
6.3 Gateway Characteristics .................................................................................................................................21
6.4 Gatekeeper Characteristics.............................................................................................................................24
6.5 Multipoint Controller Characteristics............................................................................................................25
