T.120
From Wikipedia, the free encyclopedia
T.120 is a suite of point-to-multipoint communication protocols for teleconferencing, videoconferencing, and computer-supported collaboration.[1] It provides for application sharing, online chat, file sharing, and other functions. The protocols are standardised by the ITU Telecommunication Standardization Sector (ITU-T).[1]
T.120 has been implemented in various real-time collaboration programmes, including WebEx and NetMeeting.[2][3] IBM Sametime switched from the T.120 protocols to HTTP(S) in version 8.5.[4]
The prefix T designates the ITU subcommittee that developed the standard, but it is not an abbreviation. The ITU (re)assigns these prefixes to committees incrementally and in alphabetic order.[5]
The T.123 standard specifies that T.120 protocols use network port 1503 when communicating over TCP/IP.[5]
Components
| Number | Title | Status | Refs |
|---|---|---|---|
| T.120 | Data protocols for multimedia conferencing | In force | [6] |
| T.121 | Generic application template | In force | [7] |
| T.122 | Multipoint communication service - Service definition | In force | [8] |
| T.123 | Network-specific data protocol stacks for multimedia conferencing | In force | [9] |
| T.124 | Generic Conference Control | In force | [10] |
| T.125 | Multipoint communication service protocol specification | In force | [11] |
| T.126 | Multipoint still image and annotation protocol | In force | [12] |
| T.127 | Multipoint binary file transfer protocol | In force | [13] |
| T.128 | Multipoint application sharing[a] | In force | [14][15] |
| T.130 | Realtime architecture | ? | [15] |
| T.131 | Network specific mappings | ? | [15] |
| T.132 | Realtime link management | ? | [15] |
| T.133 | Audio visual control services | ? | [15] |
| T.134 | Text chat application entity | In force | [16] |
| T.135 | User-to-reservation system transactions within T.120 conferences | In force | [17] |
| T.136 | Remote device control application protocol | Superseded by H.281 | [18][19] |
| T.137 | Virtual meeting room management for multimedia conferencing audio-visual control | In force | [20] |
| T.RES | Reservation services | ? | [3][15] |
| T.TUD | User reservation | ? | [3][15] |
- T.128 was previously called T.Share while in draft stage.