Networking
` Glossary
`
`Understanding Communications Technology
`
`A Plain English Guide to Cutting-Edgflelecommunications
`Tech nology, Terms and Acronyms
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`Aegis Publishing liroun
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`Rosetta-2007
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`0001
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`0001
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`Rosetta-2007
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`Library of Congress Catalog Card Number: 98-45440
`Copyright © 1999 by Aegis Publishing Group,'Ltd. All rights reserved. No
`part ofthispublication may bereproduced ordistributed in any form orby
`any means, or stored in -a database or retrieval system, without the prior
`written permission ofthe publisher. Requests for such permission should
`be addressed to: Aegis Publishing "Group, Ltd., 796 Aquidneck Avenue,
`Newport, RI 02842
`. International Standard Book Number: 1-890154-09-1
`Printed in the United States of America.
`
`1098765432
`Limits of liability and disclaimer of warranty: The information and
`material contained in this book are provided “as is,” without any warranty
`concerning the accuracy, adequacy, or completeness of such information
`or-. rnateri-al or the results to be obtained from using such information or
`material. Aegis Publishing Group, Ltd. shall not be responsible for any
`claims attributable to errors, omissions, or other inaccuracies in the
`information or material contained in this book, and in no event shall Aegis
`Publishing Group, Ltd. be liable for direct, indirect, special, incidental, or
`consequential damages arising out of the use of such information or
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`trademark symbols with each mention of the trademarked name, the
`publisher states thatthis book uses the names only for editorial purposes,
`and to the benefit of the trademark owner, and has no intention of
`infringing upon that trademark.
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`Library of Congress Cataloging—In-Publication Data:
`Telecom & networking glossary : understanding communications
`technology I by Aegis Publishing Group ; edited by" Robert
`Mastin.
`
`cm.
`p.
`ISBN 1-890154-09-.1 (pbk._)
`1. Telecommunication-Dictionaries.
`11. Aegis Publishing Group Ltd.
`networking glossary.
`TKS102.T42
`1998
`621.382 ' 03--dc2l
`
`I. Mastin, Robert.
`III. Title: Telecom and
`
`98-45440CIP
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`0002
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`purchased that recognize the different ring patterns and route the call to the
`appropriate device. This service goes by many names throughout the country
`including RingMate, Identa Ring, Ring Master, Personalized Ring, Custom
`Ringing, Route-a-Call, Teen Service, Multi—Line and Smart Ring. You pay a
`monthly fee per number, usually from $4 to $7, a lot less than a separate line.
`
`distribution frame A piece of equipment that interconnects wires between
`two sources, located in central offices, PBXS, or other switching facilities. In a
`central office, for example, all the subscriber’s wires come into the building and
`first connect to one side of the distribution frame. The internal C.O. wiring
`connects to the other side of the distribution frame. Jumper wires running in
`between connect the two sides, allowing for changes to be made when telephone
`numbers are changed, added, or dropped.
`
`divestiture The court—ordered separation of the Bell Operating Telephone
`Companies from AT&T in 1983, when AT&T ceased to be the monopoly
`telephone company in the United States. The seven Regional Bell Operating
`Companies (RBOCs) were given control of local phone services while AT&T
`kept the long-distance market.
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`A server that retains the addresses and routing
`domain name server
`information for TCP/IP LAN users.
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`Domain Name System (DNS) The online distributed database system that
`(a)
`is used to map human-readable addresses into Internet Protocol (IP)
`addresses, (b) has servers throughout the Internet to implement hierarchical
`addressing that allows a site administrator to assign machine names and
`addresses, (c) supports separate mappings between mail destinations and IP
`addresses, and (d) uses domain names that (i) consist of a sequence of names, i.e.,
`labels, separated by periods, i.e., dots, (ii) usually are used to name Internet host
`computers uniquely, (iii) are hierarchical, and (iv) are processed from right to
`left, such as the host nic.ddn.mil has a name (nic — the Network Information
`Center), a subdomain (ddn — the Defense Data Network), and a primary domain
`(mil — the MILNET).
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`do not disturb A service feature that lets you get work done without being
`constantly interrupted by a ringing phone. You can either turn this on and off at
`will (by pressing *78) or set up a regular schedule in advance. You can give
`family members or preferred clients a privileged “caller code” that lets their calls
`ring through anyway.
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`downlink A data link from a satellite or other spacecraft to a terrestrial
`terminal.
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`downstream In communications, the direction of transmission flow from the
`source toward the sink (destination/user).
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`DSL See digital subscriber line.
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