Cisco Systems AS5800 manual Glossary

Glossary

Glossary

AAA—Authentication, Authorization, and Accounting. AAA is a suite of network security services that provide the primary framework through which access control can be set up on your Cisco router or access server.

ACOM—Term used in G.165, “General Characteristics of International Telephone Connections and International Telephone Circuits: Echo Cancellers.” ACOM is the combined loss achieved by the echo canceller, which is the sum of the Echo Return Loss, Echo Return Loss Enhancement, and nonlinear processing loss for the call.

a-law—A voice compression technique commonly used in Europe.

ANI—Answer Number Indication. The calling number (number of calling party).

ARQ—Admission request.

Call leg—A logical connection between the router and either a telephony endpoint over a bearer channel, or another endpoint using a session protocol.

CAS—Channel Associated Signaling. In E1 applications, timeslot 16 is used to transmit CAS information. Each frame’s timeslot 16 carries signaling information (ABCD bits) for two of the B channel timeslots.

CIR—Committed Information Rate. The average rate of information transfer a subscriber (for example, the network administrator) has stipulated for a Frame Relay PVC.

codec—coder-decoder. Device that typically uses pulse code modulation to transform analog signals into a digital bit stream and digital signals back into analog signals. In Voice over IP, it specifies the voice coder rate of speech for a dial peer.

Data Link Connection Identifier (DLCI)—Frame Relay virtual circuit number corresponding to a particular destination. The DLCI is part of the Frame Relay header and is usually 10 bits long.

Dial peer—An addressable call endpoint. In Voice over IP, there are two kinds of dial peers: POTS and VoIP.

DNS—Domain Name System used to address translation to convert H.323 IDs, URLs, or e-mail IDs to IP addresses. DNS is also used to assist in the location of remote gatekeepers and to reverse-map raw IP addresses to host names of administrative domains.

DNIS—Dialed number identification service. The destination number.

DS0—A 64-Kbps channel on an E1 or T1 WAN interface.

DSP—Digital Signal Processor.

DTMF—Dual tone multifrequency. Use of two simultaneous voice-band tones for dial (such as touch tone).

E.164—The international public telecommunications numbering plan. A standard set by ITU-T which addresses telephone numbers.

E1—Wide-area digital transmission scheme. E1 is the European equivalent of a T1 line. The E1’s higher clock rate (2.048 MHz) allows for 32 64-Kbps channels, which include one channel for framing and one channel for D-channel information.

E&M—Ear and mouth RBS signaling.

Endpoint—An H.323 terminal or gateway. An endpoint can call and be called. It generates and/or terminates the information stream.

72Cisco IOS Release 12.0(7)T