Cisco BPX 8650, Installation And Configuration Manual

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Glossary
GL-8
Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
D
D channel
A message-oriented ISDN signaling channel, typically carried in DS24 of a PRI on T1 facilities or
TS16 of a PRI on E1 facilities. Compare to B channel.
D4-format
A digital signal format with 24 eight-bit channels plus one synchronizing bit per T1 line. Channels are
assigned in a straight, numeric sequence.
DACS
digital access control system.
Equipment, usually found in the telephone company central office, that is used to groom and retime the
24 channels in a DS1 signal. Individual DS0 channels can be cross-connected from one DS1 source and
inserted in another DS1 source either with the same or with a different channel number.
DAS Server Shelf
The adjunct processor used in INS Dial-Up Frame Relay applications to provide frame relay dial-up
and dial-backup circuits. The DAS Server Shelf is colocated with and connected to an IGX switch.
data
communications
equipment
See DCE.
data frame
multiplexing
See DFM.
data link
connection
identifier
See DLCI.
data terminal
equipment
See DTE.
DCE
data communications equipment.
As defined by the RS-232 standard, any device that transmits or receives information. Usually used
with data terminal equipment (DTE, like a computer or network node).
DDS
digital data service.
An AT&T dial-up data service offering for 2.4 to 56 Kbps over subscriber loop cable. Requires a Data
Service Unit, DSU, at customer premise for interface to the DDS trunk.
device code
The first 8 bits of a FastPacket Address.
DFM
data frame multiplexing.
An optional feature that saves data channel bandwidth by analyzing data channel content and
suppressing repetitive data patterns.
dial access
switching
Another name for the INS Dial-Up Frame Relay application.
Dial-Up Frame
Relay
An INS application that uses a DAS Server Shelf and software to enhance Cisco WAN switching
networks with frame relay soft permanent virtual circuits (SPVCs) for dial-up dial-backup connections.
digital access and
control system
See DACS.
digital data service
See DDS.