Cisco BPX 8650, Руководство по установке и настройке

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Glossary
GL-7
Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
consollidated link
layer management
See CLLM.
constant bit rate
See CBR.
Consultive
Committee for
International
Telephone and
Telegraph
See CCITT.
control port
An RS-232 port on the face plate of a back card for a controller card (BCC, NPC, NPM.) that may used
for connecting a control terminal. This port is bidirectional.
CoS
class of service.
The priority assigned each user connection. Defines which circuits get rerouted first during a network
failure.
CoSB
class of service buffer.
A buffer or queue that serves connections with similar QoS requirements. Also called “qbin” (though
a qbin is a platform-specific instance, such as a BXM card.
CoS Buffer
See CoSB.
CoSB Descriptor
Template
A component of a Service Class Template that contains CoSB configurations indexed by the CoSB
number.
A qbin is a platform-specific (BXM in this case) instance of the more general CoSB.
CoSB
See Class of Service Buffer.
courtesy downing
A software feature that is used to conserve network bandwidth by automatically “downing” a voice
connection when the signaling status indicates an inactive (on-hook) circuit. The circuit is
automatically “upped” when the circuit becomes active.
CRC
cyclical redundancy check.
A method of error checking that detects errors in a block of data. Unlike parity checks, the CRC can
detect multiple data errors within the block and thus equipment using a CRC error check can derive a
error rate.
crosspoint switch
A two-dimensional data switch type that is arranged in a matrix of all input connections along one axis
and all output connections along the other axis. Each input and output line has a switch point where the
two axis intersect that can be enabled (switch closed) or disabled (switch open). The central matrix
switch providing the switching matrix for traffic routing by the BPX switch.
CSU
channel service unit.
A network protection unit that terminates any T1 span line connected to the carrier's central office,
providing receive direction regeneration and maintenance loopback for the 1.544 Mbps signal.
channel service
unit
See CSU.
cyclical redundancy
check
See CRC.