Cisco BPX 8600 Series, Руководство по установке и настройке

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Glossary
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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
D
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 and 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 co-located with and connected to an IGX switch.
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).
D channel
A message-oriented ISDN signalling channel, typically carried in DS24 of a PRI on T1 facilities or
TS16 of a PRI on E1 facilities. Compare to B channel.
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.
DLCI (Data Link
Connection
Identifier)
A field in a frame relay data packet that identifies the destination for the data.
domain
A grouping of nodes sharing common interests or attributes.
domain name
A unique name consisting of the letter “D” immediately followed by a number (1–8) delineated by a
“.” (period) from the node name (1–8 characters maximum). Example: D1.alpha.
domain number
A number from 1–8 assigned with the cnfdmn command. The number assigned is part of the domain
name.
DPNSS
Digital Private Network Signalling System. A common-channel message-oriented signalling protocol
commonly used by private branch exchanges (PBXes). The INS Voice Network Switching application
supports DPNSS signalling.
DS0 (Digital Signal
0)
A 64 Kbps channel used to transmit encoded voice and/or data. There are 24 DS0 channels in a circuit
T1 (DS1) line. DS0 data is transmitted using one or more DS0 circuits in a T1 or E1 circuit line.
DS0A
An extension of DS0 that defines the format for assembling various low-speed data circuits (1.2 to 19.6
Kbps) into a single 64 Kbps DS0 channel.