T HE N ETWORK P RESS E NCYCLOPEDIA OF N ETWORKING 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   The Encyclopedia of Networking      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 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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[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 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. Table of Contents Introduction ix Entries (Listed Alphabetically) 1 Appendix A: Acronyms and Abbreviations 1113 Appendix B: Bibliography and Other Resources 1235 Index 1251 [...]... tried to make this Encyclopedia a comprehensive source of information about matters relating to networking I’ve also tried to present the information in a clear and useful manner This book contains comprehensive, straightforward summaries of the major concepts, issues, and approaches related to networking Networking is defined broadly to encompass configurations ranging from a couple of connected computers... this segment address DOS uses segmented addresses Paged Address Certain types of address space actually consist of two types of values For example, in expanded memory, locations in a special set of chips, and hence, in a special set of addresses, are mapped into special memory buffers These buffers are broken into pages of a specific size Virtual memory also uses paged addresses E-Mail Address An e-mail... applications and other software, software version control, bug reporting and resolution, and so on Help: Training users, providing documentation for using the system resources and applications, and offering other support Levels of Administration Various levels of administration are distinguished, including the following: System: Refers to a particular division in a company or a particular type of hardware, such... locations The type of address used in a particular context depends partly on which protocol or device is creating the address Address information may be maintained in any of several ways, such as in look-up tables or directories Some common types of network-related addresses are hardware, network, node, Internet, and e-mail (electronic mail) There are other types of addresses, and not all types of addresses... systems, such as NetWare, support internal addresses See the figure “Examples of network addresses” for an illustration of the kinds of addresses discussed so far Internet Address An Internet address is a network-layer address that uniquely identifies a node on an internetwork or on the Internet This type of address uses four bytes of storage, and it is generally represented as four decimal values separated... connected computers just a few feet apart to a network of several thousand machines (of all types and sizes) scattered around the world You’ll find discussions of networking as it’s done by servers and clients, managers and agents, peers, and even over the telephone You probably won’t find anything here that you can’t find in other places However, I don’t know of any other book or source that collects so much... 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... 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 B RO A D E R C A T E G O R I E S MD (Management... 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 and output wires This type of. .. 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 the fiber’s core as the cone’s point w Access . E DITION   The Encyclopedia of Networking      The Encyclopedia of Networking Second Edition   T he First Edition of this  book was published. damages 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