NEWTON’s
`
`TELECOM
`DIGTIONAR
`
`
`
` 15th Updated, Expanded and Much
`
`
`Improved Edition
`
`The Official Dictionary of
`Telecommunications & the Internet
`
` EX. 3003
`
`

`
`:..___
`
`||EW'I'0N's 'I'EI.ECOM DICTIONARY
`
`Copyright © 1999 Harry Newton
`email: Harry@HarryNewton.com
`personal web site: www.HarryNewton.com
`nal and Pan-American Copyright conventions, incl
`All rights reserved under lnternatio
`in any form whatsoever.
`to reproduce this book or portions thereof
`
`uding the right
`
`Tenth floor
`12 West 21 Street
`New York, NY 10010
`212-691-8215 Fax 212-691-1191
`1-800-999-0345 and 1-800-LlBRARY
`
`lSBN Number 1-57820-031-8
`
`tor intormation on special discounts tor quantity orders,
`
`August, 1999
`
`For individual orders, and
`Telecom Books
`6600 Silacci Way
`Gilroy, CA 95020
`Tel:800—LlBRARY or 408-848-3854
`Fax:408—848-5784
`Email:telecom@rushorder.com
`trade in the US. and Canada by
`
`Manufactured in the United States of America
`
`
`
`

`
`
`
`
`
`and lite pg-5
`ppiic i‘
`dataa mm:
`
`C0
`
`'
`
`not match, the recipient asks the sender to res
`Finally, TCP
`uses port IDs to specify which
`ning on the system is sending or receiving the
`The port ID, checksum, and sequence
`into the TCP packet in a special section c
`header is at the beginning of the packet
`other "control" information for TCP.
`How IP Works: IP is the messenger protocol oiit,‘
`protocol, much simpler than TCP, basically and
`sends packets. IP relies on three pieces of information
`you provide, to receive and deiive
`address, subnet mask, and deiauitg
`_
`The IP address identities your system on the TC
`IP addresses are 32-bit addresses that are glnbau
`a network. They are generally represented in not
`notation, which separates the tour bytes of the address gig
`periods. An IP address looks like this: 102.54.il4.9i
`Aithough an IP address is a single value, it reallyconiairrsfi
`pieces of information: (a.) Your system's network ID and" '
`Your system's host (or system) ID.
`‘
`The subnet mask, also represented in dotted decirnai
`tion, is used to extract these two values irom your lPadng3;§
`The value of the subnet mask is determined by selling Ilrargii
`work JD bits of the JP address to ones and the host in big-gt
`zeros. The resuit allows TCPIIP to determine the host anti‘)-‘rid
`work IDs of the local workstation. Here's how to understand
`IP address. For exampie;
`When the IP address is 102.5494.
`And the subnet mask is 255.255.0.
`The network ID is 102.54 (IP add
`And the host lD is 94.97 (iP address and subnet
`OK. the above was iv‘licrosoft's definition. l-lere‘s my
`which covers some areas Microsoft doesn't. TCPlIP'
`rsasei
`protocois developed by the Department of Defense to ltnlrmr
`similar computers across many kinds of networks, incirdm
`unreliable ones and ones connected to dissimilar Bilbo
`TCP/IP is the protocol used on the Internet. it is,
`to assert.
`the glue that binds the Internet. Developed in the 19705
`US. Department of Defenses Advanced Research P
`Agency (DABPA) as a military standard protocol,
`its
`ance of multi vendor connectivity has made it popular
`commercial users
`
`
`
`NEWTON'S TELECOM DICTIONARY
`
`2. An ATM term. Test Coordin
`ation Procedure: A set of rules
`to coordinate the test
`process between the lower tester and the
`upper tester. The purpose is to enable the lowertester to con-
`trol the operation of the upper tester. These procedures may,
`or may not, be specified in an abstract test suite.
`Processor.
`Tc?/IP According to Microsoft: Transmission Control
`Protocol/Internet Protocol (TCP/IP) is a networking protocol
`that provides communication across interconnected net-
`works. between computers with diverse hardware architec-
`tures and various operating systems. TCP (Transmission
`Control Protocol) and IP (Internet Protocol) are only two pro-
`tocols in the family of Internet protocols. Over time, however,
`"T013/h°_" has been used in industry to denote the family of
`c9.Uimo_n Internet protocois. The Internet protocols are a result
`of a Defense Advanced Research Protects Agency (DARPA)
`research project on network interconnection in the late 1970s.
`it was mandated on all United States defense long—haui net
`works in 1983 but was notwidely accepted until the integra-
`tion with 4.2 BSD (Berkeley Software Distribution) UNJX. The
`popularity of TOP/iP (Harry’s note: it's the internets network-
`ing protocol) is based on:
`- Robust client-server framework. TCP/iP is an excellent
`ciient—server application ' platform, especially in wide—area
`network (WAN).environments.
`- Information sharing. Thousands of academic, detense, soi-
`entific, and commercial organizations share data, electronic
`mail and services on the connected Internet using TGP/iP.
`- General availability. implementations of TCP/lP are available
`on nearly every popular computer operating system. Source
`code is widely available for many implementations. Additionally,
`bridge, router and network analyzer vendors all offer supportfor
`the TC P/lP protocol family within their products.
`TCP.llP is the most complete and accepted networking proto-
`col available. Virtually all modern operating systems offer
`TCP/IP support, and most large networks rely on TCPAP for
`a_ii their network traffic. Microsoft TOP/iP provides cross-plat-
`icrm connectivity and a client—server development framework
`that many software vendors and corporate developers are
`using to develop distributed and client-server applications in
`heterogeneous enterprise networks over TCP/IP.
`How TCP Works: TCP is a reliable, connection-oriented pro-
`tocol. Connectlon-oriented implies that TCP first establishes
`a connection between the-tvvo systems that intend to exchange
`data. Since most networks are built on shared media (for
`example, several systems sharing the same cabling), it is nec-
`essary to break chunks of data into manageable pieces so that
`no two communicating computers monopolize the network.
`These pieces are called packets. when an application sends a
`message to TCP for transmission, TCP breaks the message
`into packets, sized appropriately for the network, and sends
`them over the network
`Because a single message is often broken into many packets,
`TCP marks these packets with sequence numbers before send«
`log them. The sequence numbers atiow the receiving system
`to properly reassemble the packets into the original message.
`Being able to reassembie the original message is not enough,
`the accuracy of the data must also be verified. TCP does this
`try computing a checksum. A checksum is a simple mathe~
`maticai computation applied, by the sender, to the data con-
`tained in the TCP packet. The recipient then does the same cal-
`culation on the received data and compares the result with the
`checksum that the sender competed. if the resuits match, the
`recipient sends an acknowledgment (ACK).
`if the results do
`
`
`
`_
`
`
`
`the protocol commonly used over nrartii Wig
`LAi\is (as well as X.25) networks. it has been rrnplemetilti
`everything from PC LANs to minis and mainframes-'
`TCP/IP currently divides networking fonctronairli‘ ill!“
`four la ers:
`-
`ANetwlcrkinterface Layerthatcorresponds tothe03'
`and Data Link Layers. This layermanages ihe_errcnang?)ed
`between a device and the network to which it is ailrrc- :
`routes data between devices on the same network.
`An Internet Layer which corresponds to the 0st nel‘{i°.m
`The Internet Protocol (re) subset of the rcPrIP silt row
`this layer. iP provides the addressing needed to aliovlrmi
`to forward packets across a multiple LAN inter nH_w,g
`tEEE terms,
`it
`iirovides connectioniess daIa0l3L"U£-
`-
`'-
`which means it attempts to deliver every Dflfilifil
`"E3.‘Q.-
`provision for retransmitting lost or damatif‘-ll
`[W-935.
`'
`
`leaves such error correction, if required, to hiflllelg
`-
`"
`tocois, such as TCP.