
Glossary
61203086L1-1
ISU 512e User Manual
Glossary-3
certain line-conditioning functions, ensures network compliance
per FCC rules, and responds to loopback commands from the cen-
tral office. Also ensures proper 1s density in transmitted bit
stream and performs bipolar violation correction. See DSU.
D-channel
The ISDN channel that carries signaling information to control the
call setup, teardown, or invocation of supplementary services.
The D-Channel may also be used to provide Packet Mode Data
Service.
DCE
Data communications equipment. The portion of a data terminal
that provides the interface to the network.
DDS
Dataphone digital service. AT&T private line service for transmit-
ting data over a digital system. The digital transmission system
transmits electrical signals directly, instead of translating the sig-
nals into tone of varied frequencies as with traditional analog
transmission systems. Digital techniques provide more efficient
use of transmission facilities, resulting in lower error rates and
costs than analog systems.
digital loopback
Technique for testing the digital processing circuitry of a commu-
nications device. May be initiated locally or remotely via a tele-
communications circuit. Device being tested will echo back a
received test message after first decoding and then encoding it.
The results are compared with the original message (compare
with analog loopback).
DSU
Data service unit. A device providing an interface between a data
terminal or other data communications device and a digital access
line.
DTE
Data terminal equipment. The portion of a data terminal that in-
terfaces to the end-user’s equipment. The main difference be-
tween DCE and DTE is that pins 2 and 3 are reversed on the RS-
232.
EIA-232
An EIA-specified physical interface with associated electrical sig-
naling between DCE and DTE. The most commonly employed
interface between computer devices and modems.
Содержание 1203086L1
Страница 1: ...ISU 512e ISDN Service Unit Part Number 1203086L1 Document Number 61203086L1 1A September 1999 ...
Страница 18: ...xviii ISU 512e User Manual 61203086L1 1 List of Figures ...
Страница 20: ...xx ISU 512e User Manual 61203086L1 1 List of Tables ...
Страница 24: ...Quick Start Guide Quick Start 4 ISU 512e User Manual 61203086L1 1 ...
Страница 34: ...Chapter 2 Installation 2 6 ISU 512e User Manual 61203086L1 1 ...
Страница 46: ...Chapter 3 Operation 3 12 ISU 512e User Manual 61203086L1 1 ...
Страница 54: ...Chapter 4 Status Menu 4 8 ISU 512e User Manual 61203086L1 1 ...
Страница 58: ...Chapter 5 Test Menu 5 4 ISU 512e User Manual 61203086L1 1 ...
Страница 96: ...Chapter 6 Configuration Menu 6 38 ISU 512e User Manual 61203086L1 1 ...
Страница 100: ...Chapter 7 Dial Menu 7 4 ISU 512e User Manual 61203086L1 1 ...
Страница 130: ...Appendix C Loop Status Messages C 4 ISU 512e User Manual 61203086L1 1 ...
Страница 140: ...Appendix E SNMP E 4 ISU 512e User Manual 61203086L1 1 ...
Страница 162: ......