Instruction manual

DEFINITY® Business Communications System and GuestWorks® Issue 6
Overview
555-231-208
Issue 1
April 2000
Glossary and Abbreviations
GL-8
Center-Stage Switch
The Center-Stage Switch is a connection hub that provides port network communication. It is an
essential component of a system configuration if the system is composed of more than three port
networks.
central office (CO)
The location housing telephone switching equipment that provides local telephone service and
access to toll facilities for long-distance calling.
central office (CO) codes
The first three digits of a seven-digit public-network telephone number in the United States.
central office (CO) trunk
A telecommunications channel that provides access from the system to the public network through
the local CO.
CEPT1
European Conference of Postal and Telecommunications Rate 1
channel
1. A circuit-switched call.
2. A communications path for transmitting voice and data.
3. A DS0 on a T1 or E1 facility not specifically associated with a logical circuit-switched call;
analogous to a single trunk.
channel negotiation
The process by which the channel offered in the Channel Identification Information Element (CIIE)
in the SETUP message is negotiated to be another channel acceptable to the switch that receives
the SETUP message and ultimately to the switch that sent the SETUP. Negotiation is attempted
only if the CIIE is encoded as
Preferred .
circuit pack
A board on which electrical circuits are printed, and IC chips and electrical components are
installed. A circuit pack is installed in a switch carrier.
CISPR
International Special Committee on Radio Interference
Class of Restriction (COR)
A feature that allows up to 95 classes of call-origination and call-termination restrictions for
telephones, telephone groups, data modules, and trunk groups. See also Class of Service (COS)
.
Class of Service (COS)
A feature that uses a number to specify if telephone users can activate the Automatic Callback, Call
Forwarding All Calls, Data Privacy, or Priority Calling features. See also Class of Restriction (COR)
.
CO
See central office (CO)
.
common-control switching arrangement (CCSA)
A private telecommunications network using dedicated trunks and a shared switching center for
interconnecting company locations.
communications system
The software-controlled processor complex that interprets dialing pulses, tones, and keyboard
characters and makes the proper connections both within the system and external to the system.
The communications system itself consists of a digital computer, software, storage device, and
carriers with special hardware to perform the connections. A communications system provides