Networking the complete reference, third edition bobbi sandberg

Networking the complete reference, third edition bobbi sandberg Networking the complete reference, third edition bobbi sandberg Networking the complete reference, third edition bobbi sandberg Networking the complete reference, third edition bobbi sandberg Networking the complete reference, third edition bobbi sandberg Networking the complete reference, third edition bobbi sandberg Networking the complete reference, third edition bobbi sandberg

Copyright © 2015 by McGraw-Hill Education All rights reserved Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher ISBN: 978-0-07-182765-2 MHID: 0-07-182765-X The material in this eBook also appears in the print version of this title: ISBN: 978-0-07-182764-5, MHID: 0-07-182764-1 eBook conversion by codeMantra Version 1.0 All trademarks are trademarks of their respective owners Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intention of infringement of the trademark Where such designations appear in this book, they have been printed with initial caps McGraw-Hill Education eBooks are available at special quantity discounts to use as premiums and sales promotions or for use in corporate training programs To contact a representative, please visit the Contact Us page at www.mhprofessional.com Information has been obtained by McGraw-Hill Education from sources believed to be reliable However, because of the possibility of human or mechanical error by our sources, McGraw-Hill Education, or others, McGraw-Hill Education does not guarantee the accuracy, adequacy, or completeness of any information and is not responsible for any errors or omissions or the results obtained from the use of such information TERMS OF USE This is a copyrighted work and McGraw-Hill Education and its licensors reserve all rights in and to the work Use of this work is subject to these terms Except as permitted under the Copyright Act of 1976 and the right to store and retrieve one copy of the work, you may not decompile, disassemble, reverse engineer, reproduce, modify, create derivative works based upon, transmit, distribute, disseminate, sell, publish or sublicense the work or any part of it without McGraw-Hill Education’s prior consent You may use the work for your own noncommercial and personal use; any other use of the work is strictly prohibited Your right to use the work may be terminated if you fail to comply with these terms THE WORK IS PROVIDED “AS IS.” McGRAW-HILL EDUCATION AND ITS LICENSORS MAKE NO GUARANTEES OR WARRANTIES AS TO THE ACCURACY, ADEQUACY OR COMPLETENESS OF OR RESULTS TO BE OBTAINED FROM USING THE WORK, INCLUDING ANY INFORMATION THAT CAN BE ACCESSED THROUGH THE WORK VIA HYPERLINK OR OTHERWISE, AND EXPRESSLY DISCLAIM ANY WARRANTY, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE McGraw-Hill Education and its licensors not warrant or guarantee that the functions contained in the work will meet your requirements or that its operation will be uninterrupted or error free Neither McGraw-Hill Education nor its licensors shall be liable to you or anyone else for any inaccuracy, error or omission, regardless of cause, in the work or for any damages resulting therefrom McGraw-Hill Education has no responsibility for the content of any information accessed through the work Under no circumstances shall McGraw-Hill Education and/or its licensors be liable for any indirect, incidental, special, punitive, consequential or similar damages that result from the use of or inability to use the work, even if any of them has been advised of the possibility of such damages This limitation of liability shall apply to any claim or cause whatsoever whether such claim or cause arises in contract, tort or otherwise Great thanks and humble appreciation to all of those who helped with this book And to my kids and their kids, and ever and always to Sandy About the Author Bobbi Sandberg is a small business consultant and retired CPA who has been a trainer, instructor, and teacher of all things computer in the Pacific Northwest for more than 40 years She has “played” with computers since they occupied entire rooms and required perforated paper tape and punch cards Today, she teaches hardware and software classes, solves hardware and software issues for a number of clients, and keeps networks functional on a regular basis Bobbi is the author or coauthor of several computer books, including QuickBooks 2015: The Small Business Guide, Quicken 2015: The Official Guide, Quicken 2014: The Official Guide, Microsoft Office 2013 QuickSteps, and Computing for Seniors QuickSteps About the Technical Editors Randal Nollan has been working with technology since the late 1970s when he wrote his first program on pink punch cards Randal joined the U.S Navy in 1980 as an Aviation Ordnanceman and retired in 2001 During that time, he maintained the dBase III vaccination database for the squadron corpsman and was always in the thick of maintaining the token ring network, computers, and terminals they had at the time He graduated from Skagit Valley College CIS (networking) and MIT (programming) in 2003 He worked in Internet tech support from 2003 to 2005 and has since been working in computer repair for a local telephone company on Whidbey Island, Washington In his spare time, he enjoys the outdoors by fishing, crabbing, bicycling, camping, and hunting Indoor fun includes playing with anything tech related, remodeling his home, and making wine from any fruit that lands on his doorstep; some time he may even stop working and drink it Dwight Spivey is the author of more than 20 books on computers and technology and has happily lent his expertise as a technical editor to several more titles Dwight is happily married to Cindy, and they reside on the Gulf Coast of Alabama along with their four children He studies theology, draws comic strips, and roots for the Auburn Tigers in his ever-decreasing spare time Van Aguirre is an information technology specialist who has broad experience in the field Since the late 1990s, he has developed and taught courses in networking and multimedia technology, computing security, computer crime forensics, IT risk management, IT business continuity, and disaster recovery planning Working with other IT professionals, he has planned and managed the implementation of evolving technologies, including virtualization, mobile, and cloud computing to support institutional business and strategic initiatives As a project manager in educational technology, Van has established and promoted successful apprenticeship programs in IT desk service management for college students, integrating LEAN principles and ITIL processes to supplement technical skills Contents Acknowledgments Introduction Part I Network Basics Chapter What Is a Network? Local Area Network Baseband vs Broadband Packet Switching vs Circuit Switching Cables and Topologies Media Access Control Addressing Repeaters, Bridges, Switches, and Routers Wide Area Networks Protocols and Standards Clients and Servers Operating Systems and Applications Chapter The OSI Reference Model Communications Between the Layers Data Encapsulation Horizontal Communications Vertical Communications Encapsulation Terminology The Physical Layer Physical Layer Specifications Physical Layer Signaling The Data Link Layer Addressing Media Access Control Protocol Indicator Error Detection The Network Layer Routing Fragmenting Connection-Oriented and Connectionless Protocols The Transport Layer Protocol Service Combinations Transport Layer Protocol Functions Segmentation and Reassembly Flow Control Error Detection and Recovery The Session Layer Dialog Control Dialog Separation The Presentation Layer The Application Layer Part II Network Hardware Chapter Network Interface Adapters NIC Functions NIC Features Full Duplex Bus Mastering Parallel Tasking Wake-on-LAN or Wake-on-Wireless-LAN Selecting a NIC Protocol Transmission Speed Network Interface Bus Interface Bottlenecks ISA or PCI? Integrated Adapters Fiber-Optic NICs Portable Systems Hardware Resource Requirements Power Requirements Server vs Workstation NICs Chapter Network Interface Adapters and Connection Devices Repeaters Hubs Passive Hubs Repeating, Active, and Intelligent Hubs Token Ring MAUs Hub Configurations The Uplink Port Stackable Hubs Modular Hubs Bridges Transparent Bridging Bridge Loops Source Route Bridging Bridging Ethernet and Token Ring Networks Routers Router Applications Router Functions Routing Tables Windows Routing Tables Routing Table Parsing Static and Dynamic Routing Selecting the Most Efficient Route Discarding Packets Packet Fragmentation Routing and ICMP Routing Protocols Switches Switch Types Routing vs Switching Virtual LANs Layer Switching Multiple-Layer Switching Chapter Cabling a Network Cable Properties Cabling Standards Data Link Layer Protocol Standards Coaxial Cable Thick Ethernet Thin Ethernet Cable Television Twisted-Pair Cable Unshielded Twisted-Pair Category 5e Cat and 6a Cat Connector Pinouts Shielded Twisted-Pair Fiber-Optic Cable Fiber-Optic Cable Construction Fiber-Optic Connectors Chapter Wireless LANs Wireless Networks Advantages and Disadvantages of Wireless Networks Types of Wireless Networks Wireless Applications The IEEE 802.11 Standards The Physical Layer Physical Layer Frames The Data Link Layer Data Link Layer Frames Media Access Control Chapter Wide Area Networks Introduction to Telecommunications WAN Utilization Selecting a WAN Technology PSTN (POTS) Connections Leased Lines Leased-Line Types Leased-Line Hardware Leased-Line Applications ISDN ISDN Services ISDN Communications ISDN Hardware DSL Switching Services Packet-Switching Services Circuit-Switching Services Frame Relay Frame-Relay Hardware Virtual Circuits Frame-Relay Messaging ATM The Physical Layer The ATM Layer The ATM Adaptation Layer ATM Support SONET Chapter Server Technologies Purchasing a Server Using Multiple Processors datagram packing, 256–259 DNS names, 244–245 ICMP, 266 ICMP error messages, 266–270 ICMP query messages, 270–271 IP address classes, 240–241 IP address registration, 239–240 IP addressing, 256 IP (Internet Protocol), 255–256 IP versions, 237 ipconfig command, 490 IPv4, 237–239 IPv6, 263–264 IPv6 address structure, 265 IPv6 address types, 264–265 LCP frame in PPP, 248–250 netstat command, 488–490 network addressing, network control protocols in PPP, 250–251 nslookup utility, 490 overview of, 235 pathping utility, 487 ping utility, 483, 485–487 ports and sockets, 244 PPP connections, 251–253 PPP frame format, 247–248 PPP (Point-to-Point Protocol), 246–247 protocol stack, 14 route command, 488 routing, 261–262 SLIP (Serial Line Internet Protocol), 245–246 special IP addresses, 241–242 standard, 236 subnet masks, 239 subnetting, 242–243 task offloading, 414 TCP, 272 TCP connection establishment, 274–276 TCP connection termination, 280–281 TCP data transfer, 277–279 TCP error correction, 279–280 TCP header, 273–274 traceroute (tracert) utility, 487–488 UDP, 271–272 Unix using, 385 unregistered IP addresses, 241 utilities, 483 Windows networking architecture based on, 412 TCP (Transmission Control Protocol) connection establishment, 274–276 connection termination, 280–281 data transfer, 277–279 encapsulation and, 17 error correction, 279–280 header, 273–274 operating at transport layer of TCP/IP suite, 237 overview of, 272 three-way handshake, 339–340 transport layer functions, 29 TD (transport data), straight through wiring and, 53 TDI (Transport Driver Interface), 353–354 TDM (time division multiplexing), digital leased lines, 120 TDR (time domain reflectometry), in worst-case path calculation, 179 TE1 (terminal equipment 1), ISDN, 123–124 TE2 (terminal equipment 2), ISDN, 124 TechNet Evaluation Center, Microsoft technical support, 347 technical support, 347–348 Telecommunications Industry Association See TIA (Telecommunications Industry Association) Telecommunications Standardization Sector of International Telecommunications Union (ITU-T), 13 telecommunications, WANs, 114–115 Telenet, precursors to cloud computing, 399 telephone system, as example of circuit switching network, television cable modems, 86 telnet command applications available to Unix clients, 418 overview of, 389 Unix DARPA commands, 392 templates, system policies, 474–476 terminal equipment (TE1), ISDN, 123–124 terminal equipment (TE2), ISDN, 124 tftp command, Unix, 392–393 TGS (ticket-granting service), 434 TGT (ticket-granting ticket), 434 Thick Ethernet (10Base-5) history of, 166 maximum collision diameter, 177 overview of, 172–173 physical layer options, 172 RG-8/U, 85 Thin Ethernet (10Base-2), 173–174 history of, 166 maximum collision diameter, 177 physical layer options, 172 RG-58, 85–86 threads, Windows OSs, 349 three-way handshake, TCP, 339–340 Thunderbolt, connections for backup devices, 498, 501 TIA (Telecommunications Industry Association) cable categories, 80 cabling standards, 82 TIA/EIA-568 standard, 82–84 TIA/EIA-568 standard color codes, 87 TIA/EIA-568 standard for connector pinouts, 89–90 ticket-granting service (TGS), 434 ticket-granting ticket (TGT), 434 time division multiplexing (TDM), digital leased lines, 120 time domain reflectometry (TDR), in worst-case path calculation, 179 time exceeded, ICMP error messages, 269–270 Time to Live (TTL) cache data persistence, 297 discarding packets and, 70 timing calculations for 100Base Ethernet, 193–194 calculating network performance over Ethernet, 178–180 TLS (Transport Layer Security), 460 token-based authentication, 435–436 token frame, Token Ring, 218 token passing FDDI, 228 monitoring, 216 Token Ring, 213–214 types of media access control, 8, 24 Token Ring bridging Ethernet and Token Ring networks, 61–62 cabling options, 210 calculating adjusted ring length, 213 Differential Manchester, 21–22 errors, 218–220 fragmenting and, 26 frames, 218 MAC addresses, 23 MAUs, 52–53, 211–213 monitors, 216–218 NICs, 211 overview of, 209 packet fragmentation, 70 physical layer, 209–210 STP cable used with, 92 system capability for joining, 214–215 system operational states, 215–216 token passing, 213–214 translational bridging, 62 types of media access control, 24 tokens comparing Token Ring and Ethernet, 209 defined, 213 top-level domains, 287–288 topologies bus, 54 cabling patterns, 5–7 FDDI, 221–224 Fibre Channel, 145–146 full mesh, 159–160 infrastructure, 101, 451 physical layer, 101–104 physical vs logical, protocols contrasted with, 22 ring, 209–210, 221 star bus, 9, 159, 210, 212 WAN, 115–117 TP (twisted pair)-PMD standard, FDDI sublayers, 224–225 TP0 to TP4, classes of transport layer protocols, 28 traceroute (tracert) utility overview of, 487–488 Unix and, 389 traffic, accessing wireless networks, 98 transaction state, POP3, 340 transceivers physical layer signaling, 19 for ThickNet cabling, 173 transfer syntax, presentation layer, 33 transitive trusts, trust relationships between domains, 366 translational bridging, 62 Transmission Control Protocol See TCP (Transmission Control Protocol) Transmission Control Protocol/Internet Protocol See TCP/IP (Transmission Control Protocol/Internet Protocol) transmission power accessing wireless networks, 98 LANs vs WANs, 116 transmission rates DSL, 124 NIC selection and, 43 transmit state, Token Ring, 215 transmitter address (TA), MAC frame address field, 110 transparent bridging bridging Ethernet and Token Ring networks, 61–62 overview of, 58 source route transparent bridging, 63 transport data (TD), straight through wiring and, 53 Transport Driver Interface (TDI), 353–354 transport layer, of OSI model error detection and recovery, 29–30 flow control, 29 overview of, 27 protocol functions, 29 protocol service combinations, 27–28 segmentation and reassembly of packets, 29 Transport Layer Security (TLS), 460 trees, Active Directory objects in, 364 overview of, 367–368 planning, 375–376 troubleshooting tools See utilities truncated binary exponential backoff, collisions and, 170 trunk ring, double-ring in FDDI, 221 trust, relationships between domains, 366 TTL (Time to Live) cache data persistence, 297 discarding packets and, 70 TV service, over coaxial cable, 86 TWA (two-way alternate) dialog control in session layer, 31 dialog separation in session layer, 32 twist per inch, cable categories, 87 twisted pair cable cable categories, 87–89 connector pinouts, 89–92 overview of, 86 STP (shielded twisted pair), 92–93 UTP (unshielded twisted pair), 86–88 Twisted-Pair Ethernet (10Base-T/ 100Base-T), 172, 174–175 twisted pair (TP)-PMD standard, FDDI sublayers, 224–225 two-factor authentication, 435–436 two-way alternate (TWA) dialog control in session layer, 31 dialog separation in session layer, 32 TWS (two-way simultaneous) dialog control in session layer, 31 dialog separation in session layer, 32 U UDCs (universal data connectors), 210 UDP (User Datagram Protocol) DNS messaging and, 301 encapsulation and, 17 operating at transport layer of TCP/IP suite, 237 overview of, 271–272 transport layer functions, 29 UDRP (Uniform Domain Name Resolution Policy), 289 unbounded media defined, 97 physical layer, 101 UNC (Uniform Naming Convention) Unix OSs, 419 Windows OSs, 354 UNI (User Network Interface), ATM, 133 unicast addresses, IPv6, 264–265 Uniform Domain Name Resolution Policy (UDRP), 289 Uniform Naming Convention (UNC) Unix OSs, 419 Windows OSs, 354 uniform resource locators (URLs) elements for identifying/locating resources, 314–315 sockets and, 244 unique-local addresses, IPv6, 265 universal data connectors (UDCs), 210 Universal Serial Bus (USB) connections, 44 connections for backup devices, 498–500 Unix clients applications for, 418 overview of, 418 Windows and Windows interfaces, 419–420 Unix OSs advantages of Linux over, 379 architecture, 387–388 BSD Unix, 389 client access, 418–419 client/server networking, 393–395 DARPA commands, 392–393 hosts file, 283 networking with, 389 NFS (Network File System), 393–395 overview of, 385–386 permissions, 430–431 principles, 386–387 remote commands, 390–392 routing tables, 67 selecting computers for SOHO design, 153–154 Unix System V, 388–389 versions, 388 Unix System V, 388–389 unshielded cables, 81 unshielded twisted pair See UTP (unshielded twisted pair) unsignaled errors, error detection at transport layer, 30 update sequence numbers (USNs), directory replication and, 370 update state, POP3, 341 uplink port, hubs, 53–54 UPN (user principle name), assigned to user objects, 366–367 URLs (uniform resource locators) elements for identifying/locating resources, 314–315 sockets and, 244 USB (Universal Serial Bus) connections, 44 connections for backup devices, 498–500 User Datagram Protocol See UDP (User Datagram Protocol) user mode components, Windows OSs, 351–352 User Network Interface (UNI), ATM, 133 user principle name (UPN), assigned to user objects, 366–367 user profiles creating default user profile, 474 mandatory profiles, 473 overview of, 470–472 replicating, 473–474 roaming profiles, 472–473 username, securing home networks, 453 users Unix permissions, 431 Windows permissions, 426–428 USNs (update sequence numbers), directory replication and, 370 USOC standard, for connector pinouts, 89–90 utilities agents used with network analyzers, 492 cable testers, 493–494 filters, 491–492 ipconfig command, 490 NET commands, 483–485 netstat command, 488–490 network analyzers, 490–491 nslookup utility, 490 pathping, 487 ping utility, 483, 485–487 protocol analyzers, 493 route command, 488 TCP/IP, 483 traceroute (tracert) utility, 487–488 traffic analyzers, 492 Windows OSs, 481–483 UTP (unshielded twisted pair) 100Base Ethernet running on, 189 cable categories, 87–89 cable length on Ethernet networks, 51 cable options in Token Ring, 210 cable testers, 493–494 compatibility of copper cable with fiber-optic, 159 connector pinouts, 89–92 Ethernet cabling standards, 178 overview of, 86–88 physical layer cabling and, 18 selecting network medium, 154–155 straight through wiring and, 53 Twisted-Pair Ethernet (10Base-T/ 100Base-T), 174–175 V vampire tap, 173 VC (virtual channel), ATM, 134 VCI (virtual channel identifier), ATM cells, 133 VCs (virtual circuits) ATM, 134 frame relay, 129 packet-switching services, 127 VDSL (very high bit-rate digital subscriber line), 125 VeriSign certificate authority, 435 very high bit-rate digital subscriber line (VDSL), 125 video adapter, 138 virtual channel identifier (VCI), ATM cells, 133 virtual channel (VC), ATM, 134 virtual circuits See VCs (virtual circuits) virtual directories, web servers, 317 virtual memory, 350 virtual path identifier (VPI), ATM cells, 133 virtual path (VP), ATM, 134 virtual private networks (VPNs) encryption and, 461 in evolution of cloud computing, 399 VLANs (virtual LANs), 75–76 VMM (Virtual Memory Manager), in Windows OSs, 350 voice telecommunications, PBX, 118 void frames, in 100VG-AnyLAN, 205 volumes, encrypting, 459 VP (virtual path), ATM, 134 VPI (virtual path identifier), ATM cells, 133 VPNs (virtual private networks) encryption and, 461 in evolution of cloud computing, 399 vulnerabilities, wireless networks, 458–459 W W3C (World Wide Web Consortium) Extended Log File format, 316 founding of World Wide Web and, 399 Wake-on-LAN (WoL), NIC features, 42 WANs (wide area networks) ATM, 130–135 connecting to remote networks, 159 data centers providing access to, 161–162 DSL, 124–125 firewalls and, 442 frame relay, 127–130 ISDN, 121–124 leased lines, 118–121 local area networks compared with, 9–10 overview of, 113–114 PSTN connections, 117–118 router applications and, 64 selecting topology, 115–117 selecting WAN protocol for internetwork design, 159–160 SONET, 136 switching services, 125–127 telecommunications and, 114–115 WAPs (wireless access points) accessing wireless networks and distance from, 98 defined, 97–98 overview of, 450 setting up, 450–451 web servers functions of, 314–317 HTTP role in browser/server communication, 318 overview of, 313 selecting, 314 well-known ports, 244 WEP (Wired Equivalent Privacy) backing up wireless networks, 501 risks related to unsecured home networks, 458 whitelists, securing home networks, 454 whole disk (full-disk) encryption, 459 Wi-Fi Protected Access See WPA (Wi-Fi Protected Access) Wi-Fi Protected Setup (WPS), 459 wide area networks See WANs (wide area networks) WiFi, as most widely used wireless network, 98 Win16 environment subsystem, 351–352 Win32 environment subsystem, 351 Windows accessing command prompt, 482 interface for Unix clients, 419–420 setting environment variables, 466–467 versions of Windows network operating systems, 346 Windows accessing command prompt, 482 interface for Unix clients, 420 setting environment variables, 467 versions of Windows network operating systems, 346–347 Windows 2000, 346 Windows clients client services, 414–415 NDIS drivers for Windows clients, 413–414 overview of, 411–412 protocol drivers for Windows clients, 414 Windows network architecture, 412–413 Windows Explorer (Windows 7), 482 Windows for Workgroups, 411 Windows Internet Naming Service (WINS) comparing DNS and Active Directory, 368 as optional Windows networking service, 361 Windows Manager, 351 Windows NT, 346 Windows OSs accessing command prompt in Windows and 8, 482 APIs and, 355–356 control panel, 359 drive mappings, 468–470 file permissions, 425 file systems, 356–357 folder permission, 424–425 kernel mode components, 348–351 locking down Windows interface with system policies, 477 Microsoft technical support, 347–348 NDIS drivers for Windows clients, 413–414 NDIS (Network Driver Interface Specification), 353 NET commands, 483–485 networking architecture, 352–353 NTFS permissions, 428–430 optional networking services, 360–361 overview and role of, 345 registry, 357–359 registry editors, 360 routing tables, 67 security model, 422–424 selecting computers for SOHO design, 153–154 server-based applications, 464–465 server-based OSs, 464 Server service, 355 service packs, 347 services, 352 setting environment variables, 466–467 storing data files, 465–466 system and group policies, 359–360 TDI (Transport Driver Interface), 353–354 user and group permissions, 426–428 user mode components, 351–352 utilities, 481–483 versions, 346–347 Windows interface for Unix clients, 419–420 Windows interface for Unix clients, 420 Workstation service, 354–355 Windows Sockets (Winsock), 355–356 Windows Vista, 346 Windows XP, 346 WINS (Windows Internet Naming Service) comparing DNS and Active Directory, 368 as optional Windows networking service, 361 Winsock (Windows Sockets), 355–356 Wired Equivalent Privacy (WEP) backing up wireless networks, 501 risks related to unsecured home networks, 458 wireless access points See WAPs (wireless access points) wireless LANs See WLANs (wireless LANs) wireless networks advantages and disadvantages of, 98–99 applications of, 98–100 backing up, 501 components, 447–448 configuring wireless routers, 451–453 encryption and, 459–461 invasion tools and vulnerabilities, 458–459 overview of, 97–98 risks related to unsecured home networks, 457–458 router types, 448–450 securing business network, 455–456 securing home network, 453–455 securing mobile devices, 456–457 securing wireless routers, 456 transmission over, 450 types of, 98 WAPs (wireless access points), 450–451 wireless routers See routers, wireless wiring closets, internetwork design, 161 WLANs (wireless LANs) data link layer, 110–113 IEEE 802.11 standards, 100 overview of, 97 physical layer frames, 106–108 physical layer media, 101–106 physical layer topologies, 101–104 wireless networks, 97–100 WoL (Wake-on-LAN), NIC features, 42 workgroups, connecting computers into, Workstation service, Windows OSs, 354–355 workstations administration of, 463 capability for joining Token Ring, 214–215 connecting to FDDI network, 222 controlling, 468 creating mandatory profiles, 473 creating roaming profiles, 472–473 drive mappings, 468–470 NIC selection and, 48 policies for restricting access, 476–479 registry of, 474 replicating profiles, 473–474 user profiles and, 470–471 World Wide Web Consortium (W3C) Extended Log File format, 316 founding of World Wide Web and, 399 World Wide Web, founding of, 399 worst-case path for 100Base Ethernet, 194 calculating network performance, 179–180 WPA (Wi-Fi Protected Access) backing up wireless networks, 501 risks related to unsecured home networks, 458 securing home networks with WPA2, 454 WPS (Wi-Fi Protected Setup), 459 wrapped ring, FDDI topology, 221 write errors, magnetic tape, 510 X X.509, ITU-T standard for certificates, 435 XDR (External Data Representation), 393 XPS, Linux file systems, 380 Z zones, DNS breaking domain name space into administrative zones, 291 transfer messages, 310–312 transfers, 300–301 ... (Thick Ethernet) 10Base-2 (Thin Ethernet) 10Base-T or 100Base-T (Twisted-Pair Ethernet) Fiber-Optic Ethernet Cabling Guidelines Exceeding Ethernet Cabling Specifications The Ethernet Frame The IEEE... cable them together, and perform most of the computing tasks they needed As the capabilities of personal computers and applications grew, so did the networks, and the technology used to build them... Christmas tree lights All of the signals transmitted by the computers on the network travel along the bus in both directions to all of the other computers The two ends of the bus must be terminated