T
Designation for the basic access on the PBX.
T.120
Data protocols for multimedia conferencing.
T.121
Audiographic conferencing.
T.122
Multipoint communications service.
T.123
Protocol stacks for audiographic and audiovisual teleconference applications.
T.124
Generic conference control.
T.434
Binary file transfer format for the telematic services.
T.xxx
ITU T series recommendations - Terminals for telematic services.
T1
Twenty-four channels incorporated into a 193-bit frame and transmitted at 1.544 Mbits/s.
T2
Designation for the primary access on the PBX.
T9
Predictive text inputting system that makes it easier and quicker to create text messages on your mobile phone.
TA
Terminal Adapter.
TAM
Telephone Answering Machine.
TAPI
Telephony API. Microsoft programming interface allowing PCs to access and control telephony equipment.
TCP
Transmission Control Protocol. The TCP part of TCP/IP. A protocol that ensures data is sent correctly over IP using error correction. Real time data such as voice and video uses UDP instead.
TDMA
Time Division Multiple Access. Cellular phone technology that multiplexes multiple digital signals on to a single high speed channel.
Telco
Generic name for a telephone company.
Telephone assistant
Includes calendar, calculator with tabulation, currency and unit/ measures conversion, notepad, world time (with alarm) and international dialling codes.
Terminal Adapter
A device that allows a computer (typically) to access an ISDN network. Analogous to a modem on a POTS network.
Thumbnail
A miniature representation of a page or image. If you click on a thumbnail on the Internet, for example, it will be magnified several times.
TPS
Telephone Preference Scheme that allows people to opt out of receiving "cold" sales calls from telesales companies.
Transmission speed
The speed at which you can send and receive information over the Internet is governed by the speed of the connection device (modem, ISDN terminal adaptor or ISDN card) and the line you're using. A normal BT line, for example, will allow you to achieve speeds of up to 56k, while a digital like BT's Home Highway, will take you up to a maximum of 128k, and a super fast digital service such as broadband, from BT Openworld, will work at speeds of up to 2Mb. That's up to 40 times faster than an analogue modem.
Triple or Tri-Band
A phone that can work on three network frequencies, e.g. 02 (900Mhz), One2One (1800Mhz) and 1900Mhz (used mostly in the USA).
Trunk line
Trunk-to-trunk transfer allows an incoming call to be extended to an external telephone number by the operator, i.e. a mobile phone, branch office, or even a home number. In conjunction with DDI, external calls can be automatically diverted out over the telephone network to another number, a common out-of-the-hours working application.
