Table Of Contents

Glossary

See also Internetworking Terms and Acronyms.

C
Cisco Unified Border Element (UBE) gatekeeper	1. Component of an H.323 conferencing system that performs call address resolution, admission control, and subnet bandwidth management. 2. Telecommunications: H.323 entity on a LAN that provides address translation and control access to the LAN for H.323 terminals and gateways. The Cisco UBE gatekeeper can provide other services to the H.323 terminals and gateways, such as bandwidth management and locating gateways. A Cisco UBE gatekeeper maintains a registry of devices in the multimedia network. The devices register with the Cisco UBE gatekeeper at startup and request admission to a call from the Cisco UBE gatekeeper.
Cisco Unified Communications Manager Express	See CME.
CiscoWorks Voice Manager	See CWVM.
CME	Cisco Unified Communications Manager Express. A call-processing solution for Cisco Unified IP phones, embedded in Cisco IOS software.(CME was previously known as Cisco CallManager Express.)
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.
CVM	Obsolete abbreviation for Cisco Voice Manager. See CWVM.
CWVM	CiscoWorks Voice Manager. A client-server, web-based voice management tool used by network administrators to configure and manage voice ports, create and modify dial plans on voice-enabled Cisco routers, and provide call monitoring and reporting features.

D
DTMF	dual tone multifrequency. Tones generated when a button is pressed on a telephone, primarily used in the U.S. and Canada.
dual tone multifrequency	See DTMF.

E
E.164	1. Name of the field in an ATM address that contains a number in E.164 format. 2. ITU-T recommendation for international telecommunication numbering, especially in ISDN, BISDN, and SMDS. An evolution of standard telephone numbers.
ear and mouth	See E&M.
E&M	Ear and mouth (or recEive and transMit). Signaling technique for two-wire and four-wire interfaces between the central office and PBX.

F
Foreign Exchange Office	See FXO.
Foreign Exchange Station	See FXS.
FXO	Foreign Exchange Office. Interface that connects local calls to a PSTN central office or PBX over a standard.
FXS	Foreign Exchange Station. Interface that connects directly to a standard telephone, fax machine, or similar device over a standard RJ-11 modular telephone cable, and supplies ringing voltage, dial tone, and similar signals to it.

G
gatekeeper	See Cisco Unified Border Element (UBE) gatekeeper.
gateway	In the IP community, an older term referring to a routing device. Today, the term router is used to describe nodes that perform this function, and gateway refers to a special-purpose device that performs an application-layer conversion of information from one protocol stack to another.
GSMAMR-NB	Global System for Mobile Adaptive Multi-Rate Narrow Band

H
H.323	H.323 allows dissimilar communication devices to communicate with each other by using a standardized communication protocol. H.323 defines a common set of codecs, call setup and negotiating procedures, and basic data transport methods.
Hot Standby Router Protocol	See HSRP.
HSRP	Hot Standby Router Protocol. Provides high network availability and transparent network topology changes. HSRP creates a Hot Standby router group with a lead router that services all packets sent to the Hot Standby address. The lead router is monitored by other routers in the group, and if it fails, one of these standby routers inherits the lead position and the Hot Standby group address.

I
iLBC	internet Low Bandwidth Codec

L
Local Dial Plan	A software object that ties together a voice port and the telephone number of a device attached to the port. Also called POTS dial plan and local dial peer.

N
nonvolatile RAM	See NVRAM.
NVRAM	nonvolatile RAM. RAM that retains its contents when a unit is powered off.

P
PBX	Private Branch Exchange. Private telephone switching system.
POTS	Plain Old Telephone Service.
POTS Dial Peer	Dial peer connected via a traditional telephony network. POTS peers point to a particular voice port on a voice network device.
Private Branch Exchange	See PBX.

Q
QoS	Quality of service. Measure of the reliability of voice over IP connections.
Quality of service	See QoS.

R
RASIP	RAS means Registration, Admission, and Status. The RASIP is the IP address used in local and remote zones on a Cisco UBE gatekeeper.

S
session initiation protocol	See SIP.
Simple Mail Transfer Protocol	See SMTP.
SIP	session initiation protocol. Protocol developed by the IETF MMUSIC Working Group as an alternative to H.323. SIP features are compliant with IETF RFC 2543, published in March 1999. SIP equips platforms to signal the setup of voice and multimedia calls over IP networks.
SMTP	Simple Mail Transfer Protocol. Internet protocol providing e-mail services.
SRST	Survivable Remote Site Telephony. A feature of Cisco IOS software that provides redundant backup IP telephony service at remote branch offices.

T
Technology prefix	Discriminators used to distinguish between gateways having specific capabilities within a given zone. In the exchange between the gateway and the Cisco UBE gatekeeper, the technology prefix is used to select a gateway after the zone has been selected. Technology prefixes can be used to tell the Cisco UBE gatekeeper that a certain technology is associated with a particular call (for example, 15# could mean a fax transmission), or it can be used like an area code for more generic routing. No standard defines what the numbers in a technology prefix mean; by convention, technology prefixes are designated by a pound (#) symbol as the last character.
TFTP	Trivial File Transfer Protocol. Simplified version of FTP that allows files to be transferred from one computer to another over a network, usually without the use of client authentication (for example, username and password).
Trivial File Transfer Protocol	See TFTP.

V
VoATM	Voice over Asynchronous Transfer Mode. Feature that carries voice traffic, such as telephone calls and faxes, over an ATM network simultaneously with data traffic.
VoFR	Voice over Frame Relay. Feature that carries voice traffic, such as telephone calls and faxes, over a Frame Relay network, simultaneously with data traffic.
Voice Network Module	A network module that installs in a slot in a router, converts telephone voice signals into a form that can be transmitted over an IP network, and provides one or two slots for voice interface cards.
Voice over Asynchronous Transfer Mode	See VoATM.
Voice over Frame Relay	See VoFR.
Voice over Internet Protocol	See VoIP.
VoIP	Voice over Internet Protocol. Feature that carries voice traffic, such as telephone calls and faxes, over an IP network, simultaneously with data traffic.
VoIP Dial Peer	A software object that ties together an IP address and a telephone number at a remote site reached over the IP network (also called remote dial peer).

Z
zone	Collection of all terminals, gateways, and multipoint control units (MCUs) managed by a single Cisco UBE gatekeeper. A zone includes at least one terminal, and can include gateways or MCUs. A zone has only one Cisco UBE gatekeeper. A zone can be independent of LAN topology and can comprise multiple LAN segments connected by routers or other devices.