Cisco Systems ATA 188, ATA 186 manual Internet Control Message Protocol, GL-3

FXO

FXS

Glossary

Foreign Exchange Office. An FXO interface connects to the public switched telephone network (PSTN) central office and is the interface offered on a standard telephone. Cisco FXO interface is an RJ-11 connector that allows an analog connection at the PSTN central office or to a station interface on a PBX.

Foreign Exchange Station. An FXS interface connects directly to a standard telephone and supplies ring, voltage, and dial tone. Cisco's FXS interface is an RJ-11 connector that allows connections to basic telephone service equipment, keysets, and PBXs.

G

G.711	Describes the 64-kbps PCM voice coding technique. In G.711, encoded voice is already in the correct
	format for digital voice delivery in the PSTN or through PBXs. Described in the ITU-T standard in
	its G-series recommendations.
G.723.1	Describes a compression technique that can be used for compressing speech or audio signal
	components at a very low bit rate as part of the H.324 family of standards. This Codec has two bit
	rates associated with it: 5.3 and 6.3 kbps. The higher bit rate is based on ML-MLQ technology and
	provides a somewhat higher quality of sound. The lower bit rate is based on CELP and provides
	system designers with additional flexibility. Described in the ITU-T standard in its G-series
	recommendations.
G.729A	Describes CELP compression where voice is coded into 8-kbps streams. There are two variations of
	this standard (G.729 and G.729 Annex A) that differ mainly in computational complexity; both
	provide speech quality similar to 32-kbps ADPCM. Described in the ITU-T standard in its G-series
	recommendations.
gateway	A gateway allows SIP or H.323 terminals to communicate with terminals configured to other
	protocols by converting protocols. A gateway is the point where a circuit-switched call is encoded and
	repackaged into IP packets.

H

H.245	An ITU standard that governs H.245 endpoint control.
H.323	H.323 allows dissimilar communication devices to communicate with each other by using a standard
	communication protocol. H.323 defines a common set of CODECs, call setup and negotiating
	procedures, and basic data transport methods.

I

ICMP Internet Control Message Protocol

Cisco ATA 186 and Cisco ATA 188 Analog Telephone Adaptor Administrator’s Guide for MGCP (version 3.0)

OL-4803-01 GL-3