T-I: Two pairs of copper wire that can carry 24 DS-O signals at a rate of 1.544 MBPS.
(TA) Terminal Adapter: An external device, which connects computers to an ISDN line.
TANDEM: A special ILEC switch which interconnects local ILEC switches directly serving providing dial tone to users with IXC or CLEC switches and/or networks.
(TCP/IP) Transmission Control Protocol/Internet Protocol: A communications protocol developed by the Department of Defense to inter-network dissimilar systems and operates at layers 3 and 4 (network and transport, respectively) of the OSI model.
(TDM) Time Division Multiplexing: A digital multiplexing method to merge signals from two or more channels, such as telephones, computers, and video, into a common channel for transmission over telephone lines.
(TELCO) Public Telephone Company: A company that provides telecommunication services.
Teleradiology: A system that enables the viewing and processing of images within a hospital's nuclear medicine departments or remote image viewing from home computers or remote sites.
(TELNET) Virtual Terminal Protocol: An Internet service that allows a user to create an interactive session with a computer on a different network as if they were actually on that system.
Tier: A package of television channels offered to customers for a single price. Most cable systems have more than one tier, e.g., a basic package including local broadcast stations, and one or more expanded tiers featuring popular cable program networks. In addition, cable operators offer premium subscription services, such as HBO and SHOWTIME, and pay-per-view events such as movies, boxing matches, and concerts.
(TMN) Telecommunications Management Network: A network using a set of international standards that interconnects and interfaces with a telecommunications network in order to interchange information in order to control and maintain the telecommunications network.
Translator: Relay system that picks up distant television signals, converts the signals to another channel to avoid interference, and retransmits them into areas the original television station could not reach.
Transponder: The part of a satellite that receives and retransmits a signal.
Transport: The transfer access service to and from a point of presence (POP) serving wire center and a customer's serving wire center or end office (EO).
Trunk: A communications network that can be used to connect circuits between switches or to interconnect switches themselves to form a network.
Trunking: Transporting signals from one central point in a cable system (such as a headend) to another site without serving customers directly. Trunking can be accomplished by using fiber optics, coaxial cable, or microwave, although fiber is now the norm for the cable industry.
(TV) Television: An electronic system of transmitting transient images and sound by means of electronic signals transmitted through wires and optical fibers.
Twisted Pair: The wire traditionally used by telephone companies to connect customers to their central offices. It consists of two or more strands of color-coded copper wire bound together in a protective sheath.
Two-Way: See INTERACTIVE.
(TWTA) Traveling Wave Tube Amplifiers: The main microwave repeaters or transmitters on a satellite.