Appendix C: Glossary and Acronyms
T1
A dedicated digital carrier facility which transmits up to 24 voice
channels (DS0s) and transmits data at 1.544 Mbps. Commonly used to
carry traffic to and from private business networks and ISPs.
T3
A dedicated digital carrier facility which consists of 28 T1 lines and
transmits data at 44.736 Mbps. Equivalent to 672 voice channels (DS0s).
TDM
time division multiplexer
A device that supports simultaneous transmission of multiple data streams
into a single high-speed data stream. TDM separates signals by
interleaving bits one after the other.
telco
A generic name which refers to the telephone companies throughout the
world, including RBOCs, LECs, and PTTs.
tip and ring
The standard termination on the two conductors of a telephone circuit;
named after the physical appearance of the contact areas on the jack plug.
twisted pair
Two copper wires commonly used for telephony and data
communications. The wires are wrapped loosely around each other to
minimize radio frequency interference or interference from other pairs in
the same bundle.
Digium, Inc.
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