T.120 is a suite of point-to-multipoint communication protocols for teleconferencing , videoconferencing , and computer-supported collaboration .[ 1] 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Superseded by H.281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.
See also
References
^ a b Clark, W. J. (1994). "Protocols for Multimedia Conferencing: An Introduction to the ITU-T T.120 series". In Hutchison, D.; Danthine, A.; Leopold, H.; Coulson, G. (eds.). Proceedings of the International COST 237 Workshop on Multimedia Transport and Teleservices . Springer-Verlag. p. 322. doi :10.1007/3-540-58759-4_43 . ^ "Evaluation of Shared Display in WebEx and VNC" . Community Grids Heritage Web Server: Summer 2000–2001 . Indiana University Bloomington. Section: "Network communication". Retrieved 13 March 2018 .^ a b c United States patent 6317777B1 , Rune A. Skarbo; Christopher C. Lawless & Puneet Kukkal et al., "Method for web based storage and retrieval of documents", issued 13 November 2001, assigned to Intel ^ Chiabra, Roberto. "What's New in Sametime 8.5" (PDF) . IBM DeveloperWorks . IBM. Retrieved 13 March 2018 . ^ a b Zwicky, Elizabeth D.; Cooper, Simon; Chapman, D. Brent (June 2000). "Multimedia Protocols" . Building Internet Firewalls O'Reilly Media . Subsection: "Packet filtering characteristics of T.120". ISBN 978-1-56592-871-8 OCLC 639935671 . Retrieved 20 February 2018 . ^ "T.120 : Data protocols for multimedia conferencing" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.121 : Generic application template" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.122 : Multipoint communication service - Service definition" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.123 : Network-specific data protocol stacks for multimedia conferencing" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.124 : Generic Conference Control" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.125 : Multipoint communication service protocol specification" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.126 : Multipoint still image and annotation protocol" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.127 : Multipoint binary file transfer protocol" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.128 : Multipoint application sharing" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ a b c d e f g Freedman, Alan. "T.120" . Computer Desktop Encyclopedia . The Computer Language Company. Retrieved 3 March 2018 . ^ "T.134 : Text chat application entity" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.135 : User-to-reservation system transactions within T.120 conferences" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.136 : Text chat application entity" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "H.281 : A far end camera control protocol for videoconferences using H.224" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .^ "T.137 : Virtual meeting room management for multimedia conferencing audio-visual control" . ITU.int . International Telecommunication Union. Retrieved 3 March 2018 .
External links
