Cisco Systems ATA187I1ARF manual Numerics, GL-1

Numerics

10BaseT

G L O S S A R Y

10-Mbps baseband Ethernet specification using two pairs of twisted-pair cabling (Categories 3, 4, or 5): one pair for transmitting data and the other for receiving data. 10BASET, which is part of the IEEE 802.3 specification, has a distance limit of approximately 328 feet (100 meters) per segment.

A

A-law

AVT tones

ITU-T companding standard used in the conversion between analog and digital signals in PCM systems. A-law is used primarily in European phone networks and is similar to the North American µ-law standard. See also companding and µ-law.

Out-of-bound signaling as defined in RFC 2833.

C

category-3 cable

CED tone detection

One of five grades of UTP cabling described in the EIA/TIA-586 standard. Category 3 cabling is used in 10BaseT networks and can transmit data at speeds up to 10 Mbps.

Called station identification. A three-second, 2100 Hz tone generated by a fax machine answering a call, which is used in the hand-shaking used to set the call; the response from a called fax machine to a CNG tone.

CELP	code excited linear prediction compression. Compression algorithm used in low bit-rate voice
	encoding. Used in ITU-T Recommendations G.728, G.729, G.723.1.
CLIP	Calling Line Identification Presentation. Shows your identity to callers with Caller ID.
CLIR	Calling Line Identification Restriction. Hides your identity from callers with Caller ID.
CNG	Comfort Noise Generation
codec	coder decoder. In Voice over IP, Voice over Frame Relay, and Voice over ATM, a DSP software
	algorithm used to compress/decompress speech or audio signals.
companding	Contraction derived from the opposite processes of compression and expansion. Part of the PCM
	process whereby analog signal values are rounded logically to discrete scale-step values on a nonlinear
	scale. The decimal step number then is coded in its binary equivalent prior to transmission. The process
	is reversed at the receiving terminal using the same nonlinear scale. Compare with compression and
	expansion. See also a-law and µ-law.

	Cisco ATA 187 Analog Telephone Adaptor Administration Guide for SIP (Version 1.0)
OL-21862-01		GL-1