T HE N ETWORK P RESS ENCYCLOPEDIA OF NETWORKING W ERNER F EIBEL N OW I MPROVED — THE M OST C OMPREHENSIVE C OMPENDIUM OF N ETWORKING C ONCEPTS , I SSUES , AND T ERMS C OVERS N ET W ARE 4.1, W INDOWS 95, W INDOWS NT S ERVER 3.51, U NIX W ARE 2, AND OS/2 W ARP C ONNECT F ULL T EXT ON CD-ROM FOR Q UICK E LECTRONIC R EFERENCE S ECOND E DITION Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com   The Encyclopedia of Networking    Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com   The Encyclopedia of Networking Second Edition  T he First Edition of this  book was published under the title Novell’s ® Complete  Encyclopedia of Networking  Werner Feibel  San Francisco ■ Paris ■ Düsseldorf ■ Soest Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com Acquisitions Editor: Kristine Plachy Developmental Editor: Guy Hart-Davis Editors: Kristen Vanberg-Wolff and Maureen Adams Technical Editor: Mary Madden Book Designer: Seventeenth Street Studios Technical Illustrators: Cuong Le, Heather Lewis, and Alan Smith Desktop Publisher: London Road Design Production Coordinator: Nathan Johanson Indexer: Matthew Spence Cover Designer: Archer Design Cover Photographer: Dewitt Jones SYBEX is a registered trademark of SYBEX Inc. 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Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com [In] a certain Chinese encyclopedia…it is written that animals are divided into: (a) those belonging to the Emperor (b) those that are embalmed (c) tame ones (d) suckling pigs (e) sirens (f) fabulous ones (g) stray dogs (h) those included in the present classification (i) those that tremble as if mad (j) innumerable ones (k) those drawn with a very fine camelhair brush (l) others (m) those that have just broken the water pitcher (n) those that look like flies from a long way off Jorge Luis Borges Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com Acknowledgments As with the first edition, this book would never have been completed without the help of many people. These people deserve thanks for all their efforts and energy. Guy Hart-Davis convinced me that it was time for a revision and set me to work. Several people did splen- did work during the production process: Kris Vanberg-Wolff, a veteran of the first edition, worked on the revision until her planned departure for the calmer (and tastier) world of cooking school. Maureen Adams, Laura Arendal, and Nathan Johanson took over the pro- duction chores after Kris left. They did an excellent job, especially considering the short notice and even shorter revision schedule. My heartfelt thanks to all these folks. Mary Madden’s technical reviews were always full of gentle, constructive corrections and useful suggestions for improvements. Although I may not have been smart enough to act on all of them, the suggestions have improved the book immensely—for which I’m very grateful. Kris Vanberg-Wolff’s eagle eyes and infallible grammatical sense found and fixed my awkward phrasings, stylistic inconsistencies, and grammatical aberrations. I shudder to think what the book would have looked like without the benefit of these efforts. As always, I’m very grateful to all the people who worked between and behind the scenes to make this book, and also to those who created the compact disc. Thanks also to the many people who sent me information about their products and who took the time to answer my questions. Finally, I dedicate this book to my wife Luanne and my daughter Molly—for all the joy and fun they provide, during both work and play hours. Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com Table of Contents Introduction ix Entries (Listed Alphabetically) 1 Appendix A: Acronyms and Abbreviations 1113 Appendix B: Bibliography and Other Resources 1235 Index 1251 Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com [...]... the range over which incoming light will be reflected and propagated through the fiber The size of this angle depends on the relative refractive indexes of the fiber core, the cladding, and the surrounding medium (which is generally air) Acceptance Cone In fiber optics, the three-dimensional analog of an acceptance angle The cone generated by revolving the acceptance angle 360 degrees with the center of. .. nodes of a 100BaseT4 network can be no further apart than 205 meters—regardless of whether the nodes are next to each other SEE 100BaseT C O M P A RE 100BaseT4; 100BaseTX w 100BaseT The general name for any of three 100 Mbps Ethernet variants that have just been made a standard by an IEEE 802.3 subcommittee (802.3u) 100BaseT Ethernet is one of the candidates trying to become the standard 100 Mbps Ethernet... pairs w 100 Mbps Ethernet Any of several proposed 100 Mbps implementations of the Ethernet network architecture Three different approaches have been proposed: 100BaseVG, 100BaseX, and fastEthernet These implementations differ most fundamentally in the media-access methods and types of cable they use w 110-Type Punch-Down Block A device for terminating wires, with the possibility of connecting input... collaboration with several other corporations The term fast Ethernet is often used for this version This is unfortunate, since that term is also used to refer to any Ethernet implementation that supports speeds faster than the of cial 10 Mbps standard To add to the confusing terminology, a software product (no longer available) was also named fastEthernet 100BaseT Ethernet retains Ethernet’s CSMA/CD (Carrier... file means the user can edit the file or redirect output to it Write access for a directory allows the user to create a file or a subdirectory Access Time In hard-disk performance, the average amount of time it takes to move the read/ write heads to a specified location and retrieve data at that location The lower the value, the better the performance Currently, hard disks with access times of less than... under the auspices of CCITT, the conglomeration of ADMDs in the world forms the backbone for a global X.400 network or a quintillion, bytes.) Digital Equipment Corporation’s Alpha APX chip is an example of a 64-bit address bus w Address Mask In the IP (Internet Protocol) addressing scheme, a group of selected bits whose values identify a subnetwork; also known as a subnet mask All the members of that... subnetwork share the same mask value Using an address mask makes it easier for the system to reference a member of a particular subnet w Address Resolution The process of mapping one type of address to another; specifically, mapping a network (local) address to a hardware-dependent address The most widely used method of address resolution is the Address Resolution Protocol (ARP) or a variation of that protocol... category 3, 4, or 5 UTP cable The T4 in the name comes from the fact that four wire pairs are needed: two for sending and two for receiving Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com 100BaseVG In some configurations, fast and ordinary Ethernet nodes can share the same network Fast Ethernet devices identify themselves as such by sending a series of FLPs (fast link pulses)... are used in the same direction at a given time s Uses the more efficient 5B/6B NRZ signal encoding, as opposed to the 100BaseT C O M P A RE 100BaseTX; 100BaseFX w 100BaseTX A 100BaseT Ethernet variant that uses two wire pairs, but requires Category 5 UTP or STP wire Two nodes of a 100BaseTX network can be no further apart than 205 meters—regardless of whether the nodes are next to each other This variant... entries for Appendix A Given the futility of even trying to stay completely up-to-date, I’ve chosen to focus on the more enduring concepts and facts—those that provide the foundations and background that underlie the constantly changing terminology This makes the Encyclopedia more generally useful and enduring Helping the Book Grow While core networking concepts change very little, the core does grow For . arising out of the use of or inability to use the software even if advised of the possibility of such damage. The exclusion of implied warranties is not permitted by some states. Therefore, the above. cabling: Two nodes of a 100BaseT4 network can be no further apart than 205 meters—regardless of whether the nodes are next to each other. The following variants of 100BaseT Ethernet have been. of the intellectual property rights of third parties which would result from such use. The first edition of this book was published under the title Novell’s ® Complete Encyclopedia of