Cisco BPX 8600 Series, Installation And Configuration Manual

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Glossary
5
Cisco BPX 8600 Series Installation and Configuration
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
C
CAS (Channel
Associated
Signalling) A signalling mode in E1 transmission where the signalling bits for all 30 E1 channels are carried in
timeslot 16. Timeslots 1 to 15 and 17 to 31 carry encoded voice bits only.
CBR (Constant Bit
Rate)
ATM Connection type for constant bit rate traffic such as voice or synchronized data requiring a low
variation in delay. (See also, VBR and ABR.)
CCDV (Compliant
Cell Delay
Variation)
A parameter utilized in defining ATM Constant Bit Rate service. The amount of delay that is acceptable
between ATM cells for them to be accepted as compliant (usable).
CCITT (Consultive
Committee for
International
Telephone and
Telegraph)
An international telecommunications advisory committee established under the United Nations to
recommend worldwide standards for data and voice communications.
CCS (Common
Channel Signalling) A carrier signalling mode in E1 transmission where signalling bits are not used. CCS typically
separates user data from signalling information. A signalling channel is used to provide signalling for
all other user data channels in the system.
CDVT (Cell Delay
Variation
Tolerance)
Controls time scale over which the PCR is policed.
Cell
A unit of data with a fixed number of bytes. For ATM the cell size is 53 bytes.
cell relay
A form of digital communications using fixed length cells consisting of data and a small header. IPX
FastPacket was an early implementation of cell relay. The 53 byte ATM cell consists of data and a small
header.
CEPT
CEPT is the European Conference of Posts and Telecommunications Administrations. This association
is comprised of European Telecommunications service providers that participate in relevant areas of
the work of CEN/CENELEC.
CGA (Carrier Group
Alarm)
A major alarm condition for a T1 multiplexer or PABX that results in all channels being taken out of
service.
channel
The logical end point for a connection.
circuit line
A T1 or E1 line that connects a user device, such as a PABX or channel bank to a switch. Carries
customer DS0 voice and data circuits. (See also line.)
Cisco StrataView
Plus
A Unix-based workstation and software used as a network management system (NMS) for Cisco WAN
switching networks. It is part of the StrataSphere group. Provides a graphical user interface for
configuration, maintenance, administration of the network. Collects and displays network statistics.
clear channel
capability
When all eight bits of a channel word in the T1 line signal are available for transmitting customer data
with no restrictions on content. Also referred to as 64 Kbps clear channel.
Cmax
A frame relay connection parameter that specifies the number of packets allowed in the initial burst of
data after which the data bandwidth is reduced to the connection's minimum specified bandwidth.