The Illustrated Network- P81
lượt xem 2
download
The Illustrated Network- P81:In this chapter, you will learn about the protocol stack used on the global public Internet and how these protocols have been evolving in today’s world. We’ll review some key basic defi nitions and see the network used to illustrate all of the examples in this book, as well as the packet content, the role that hosts and routers play on the network, and how graphic user and command line interfaces (GUI and CLI, respectively) both are used to interact with devices.
Bình luận(0) Đăng nhập để gửi bình luận!
Nội dung Text: The Illustrated Network- P81
- Index 6 to 4 tunnels, 255 Administratively scoped addresses, 407 10Base2, 87 AfriNIC (African Network Information 10G-base-er (extended range), 88 Center), 138 100BaseT, 87 Agent/manager model, 616 Ethernet LANs, 62 Agents object values, 618 A proxy, 617 Abrupt close, 292 SNMP message/command acceptance, 627 Access charges, 338 software, 616, 617, 621 Access control, 33 SSH, 640 Access points (APs), 99–100 AH. See Authentication header Active open, 56 Alternate host address message, 203 Active Service Pages (ASP), 562, 570 American National Standards Institute installation, 562 (ANSI), 17 pages, 563 American Standard Code for Information Adaptive Service Physical Interface Card Interchange (ASCII), 17 (AS PIC), 692 Anonymous FTP, 519 interface, 692 Anycast internal interface supported by, 716 addresses, 116–17 traffic match-up, 692 one-to-many relationship, 488 Address resolution, 36 Any-Source Multicast (ASM), 418 ICMPv6, 152, 153 Apache Web server software, 562 IPv6, 152–59 capture, 564, 583 Neighbor Discovery, 161–62 OpenSSL, 588 Address Resolution Protocol (ARP), 51, 58, SSL test certificate, 589 143–62, 165 “success” page, 564 arriving request, 150 APNIC (Asian Pacific Network Informa- ATM (ATMARP), 146 tion Center), 138 example operation, 155–57 Application layer, 30, 41, 59–60 exchange example, 157 interface, 52 host to host, 146 tasks, 41 host to router, 146 See also TCP/IP layers Illustrated Network, 144–45 Application programming interfaces InARP, 146, 159 (APIs), 52 IPv6 and, 159–62 Applications LANs and, 146–53 layers and, 301–4 layers and, 146 multicast, 406, 407 Proxy, 157–58 TCP/IP, 11, 41, 42–43 request and reply process, 156 UDP, 59 results, 143 ARIN (American Registry for Internet RARP, 146, 158 Numbers), 138 router to host, 147 ARP cache, 143, 156 router to router, 147 entry deletion, 151 scenarios illustration, 147 Linux display of, 151 tables, 146 Windows XP display of, 152 variations, 157–59 See also Address Resolution Protocol WANs and, 158–59 ARP messages, 153–55 Windows XP reply capture, 150 fields illustration, 154 See also ARP cache; ARP messages Hardware Size field, 155
- 770 Index ARP messages (cont’d) Authentication header (AH), 713, 723–25 Operation field, 155 Authentication Data field, 725 Protocol Size field, 155 fields, 724–25 Sender’s Ethernet Address field, ICV, 723 155 Next Header field, 724 Sender’s IP Address field, 155 packet formats, 723 Target Ethernet Address field, 155 Payload Length field, 724 Target IP Address field, 155 Reserved field, 724 Type of Hardware field, 154 Sequence Number field, 724 Type of Protocol field, 154 SPI field, 724 uses, 163 Authoritative servers, 487 See also Address Resolution Protocol Automatic IP addressing, 112 (ARP) Automatic tunneling, 253 ASN.1 (Abstract Syntax Notation version 1), Autonomous system numbers (ASNs), 618 348–49 Asymmetric DSL (ADSL), 95 Autonomous systems (ASs), 332–34 Asynchronous transfer mode (ATM), 18, 71, border routers (ASBRs), 332, 368, 369, 370 85, 434, 438–41 multihomed, 389 ATMARP, 146 RIPng and, 345 cell header, 439 router connectivity, 333 cell relay, 439 Auxiliary port, 248 connection identifier, 440 Avaya VoIP software, 738 as international standard, 439 logical links, 90 B switches, 442 Backbone routers, 246, 334 VCI, 159 architecture, 246 VPI, 159 running RIPng, 351 Attributes, BGP, 393 Backdoor links, 368 AGGREGATOR, 394 Backup Designated Router (BDR), 370–71 AS_PATH, 394 Bandwidth ATOMIC_AGGREGATE, 394 in protocol evolution, 3–6 CLUSTER_LIST, 395 QOS, 327 COMMUNITY, 394–95 Base64 encoding, 545 discretionary, 393 Beacon frames, 99 list of, 393 Berkeley Internet Name Domain (BIND), LOCAL_PREF, 394 497 mandatory, 393 Best match, 251 MULTI_EXIT_DISC, 394 Bidirectional NAT, 687–89 NEXT_HOP, 394 DNS procedure, 688–89 nontransitive, 393 illustrated, 688 ORIGIN, 394 static mapping, 688 ORIGINATOR_ID, 395 See also Network address translation transitive, 393 Binary packet protocol, 643 type format, 399 Bindings, 143 See also Border Gateway Protocol Bit synchronization, 31 (BGP) Blades, 244 Authentication, 594–95 BOOTP, 459, 468–72 RIPv2, 361 client broadcast, 468 servers, 100, 585 DHCP message comparison, 481 SMTP, 544–45 flexibility, 469 SSH, 637–38 implementation, 469 SSH-AUTH, 644–45 messages, 469–71 user, 585 relay agents, 464, 471, 472
- Index 771 requests, 468 Broadcast domains, 58, 61, 116 servers, 459, 469 collision and, 62 vendor-specific area options, 471–72 Broadcast/multicast addresses, 116 See also Dynamic Host Configuration Broadcasts, VLANs for cutting down, 67 Protocol (DHCP) Bus/broadcast topology, 31 Bootstrap programs, 245 Border Gateway Protocol (BGP), 337, C 379–401 Cable modems (CMODEMs), 85 attributes, 393–95 Call agents, 753 birth of, 387–88 Captive portal, 100 configuration groups, 383 Carrier-sense multiple access with collision configuring, 382–84 avoidance (CSMA/CA), 100 default behavior, 383 Carrier-sense multiple access with collision EBGP, 382, 389–90 detection (CSMA/CD), 87, 101 extended communities, 388 Cascading style sheets (CSSs), 570 IBGP, 382, 389–90 Cell relay, 439 Identifier, 390 Certificate authorities (CAs), 595 Illustrated Network, 380–81 Certificate revocation lists (CRLs), 595, import policy, 385 603 Internet and, 386–88 Certificates Keepalive messages, 396 Apache SSL test, 589 MBGP, 392, 413, 447–48 Details tab, 590–91 message header, 397 fields, 590 message types, 396 private key, 591 Multihop, 392 public key, 591 next hops, 390 security warning, 588 NLRI, 382 self-signed, 595 Notification messages, 396, 399–400 site, 589 Open messages, 396, 397, 398 SSL and, 604 as path vector protocol, 388–89 tests, 589 route advertisement, 389 viewing, 589, 590 routing policies, 384–86, 395–96 Certificate singing request (CSR), 604 as routing protocol, 379–86 Chained headers, 124 scaling, 395–96 Challenge Handshake Authentication session growth, 395 Protocol (CHAP), 666 speakers, 389 Checksum, 264, 266 synchronizing, 391 Chunked encoding, 573 types of, 392–93 Cipher Block Chaining (CBC), 601 universally reachable address level, Cipher Suites, 599, 600 389 Classful IPv4 addresses, 114, 118 Update messages, 396, 397–98 concepts, 120 Border routers, 334 default masks and, 128 AS, 368 illustrated, 118 EGP, 387 See also IPv4 addresses Branches, 410 Classless interdomain routing (CIDR), 117, Bridges, 63 131–35 connecting TCP/IP hosts, 64 address grouping under, 132 illustrated use, 69 aggregation, 135 operation, 60 contiguous IP addresses, 132 as protocol independent devices, 64 in operation, 135 spanning tree, 63 prefixes and addressing, 133–34, 135 Broadband ISDN (B-ISDN), 439 RFC, 132 Broadband power line (BPL), 86 Classless IP addresses, 119, 120
- 772 Index Class of service (CoS), 327, 328 FTP, 518, 521–24 Clear text encryption, 638 maximum segment size (MSS), 286 Clients, 7, 8 on-demand, 279 BOOTP broadcast, 468 permanent, 279 DNS, 463 procedures, 287 email, 538 three-way handshake, 286 FTP, 304, 513, 519, 529 Console port, 248 SSH, 639 Constrained path LSPs, 447 VoIP, 738 Contributing source identifiers (CSRC), Client–server model, 54, 55 746 application implementation, 56 Control connection, FTP peer-to-peer model versus, 55 in directory listing, 523 TCP/IP layers and, 55–57 FTP model, 522 Collocation facilities, 334 setup, 518 Command-line interface (CLI), 8, 11–12 Convergence, 435–42 Common Management Information Services/ desire for, 431 Common Management Information on Metro Ethernet links, 435 Protocol (CMIS/CMIP), 612 on TCP/IP, 441–42 Communications Cookies, 570, 580–81 layers, 22 issues, 581 layers summary, 45 screening/rejecting, 581 termination of, 15 third-party, 581 Community strings, 627 as Web state management, 580 Compressed SLIP (CSLI), 85 in Windows XP, 580 Confederations, 337 Core-based trees (CBT), 418 Configuration CS packets, 740 BGP groups, 383 Customer-edge (CE) routers, 9, 47, 670 for DHCP use, 464 CE0, 672, 716–18 multipoint, 31 CE6, 676, 718–19 physical layer, 31 Cyclic redundancy check (CRC), 33, 103 point-to-point, 31 router-by-router, 672–74 D SSH files, 640 Data connection, FTP, 521 VPLS, 672–74, 679 active mode, 524 Configured tunneling, 253 activity on, 524 Congestion control, 275 FTP model, 522 TCP, 294 illustrated, 523 UDP, 275 passive mode, 524 Connection control, 40 See also File transfer protocol (FTP) ConnectionLess Network Protocol (CLNP) Data Encryption Standard (DES), 601 packets, 372 Datagrams, 55, 165, 259 Connectionless networks, 325–28 conversion errors, 203 comparison, 325 See also User Datagram Protocol (UDP) QOS, 326–28 Datagram sockets, 306 Connection-oriented networks, 325–28 Data Link Connection Identifier (DLCI), 159, comparison, 325 437, 438 QOS, 326–28 Data link layer, 30, 32–35, 84–86 Connections, 279, 324 forwarding, 34–35 closing, 291–92 frames and, 83–84 control, 518, 522–23 functions, 32–33 data, 521–24 illustrated, 32 data transfer, 289–91 See also TCP/IP layers establishment, 288–89 Data rate, 31
- Index 773 Data transfer Dijkstra algorithm, 365 connections, 289–91 Direct delivery, 226 FTP, 521–24 MAC addresses and, 227 SSL, 601 packets on LANs, 230 TCP, 289–91 without routing, 230–31 Dead routers, 213 Windows and, 226 Decryption, 597–98 Distance Vector Multicast Routing Protocol Deep inspection, 707 (DVMRP), 417 De facto standards, 16–17 Distance-vector protocol, 354 Default gateways, 233 Distance-vector routing, 355–56 De jure standards, 16 consequences, 357–58 Delayed duplicate, 291 split horizon, 357 Demultiplexing, 301–16 triggered updates, 357–58 Dense-mode multicast, 410 Distributed coordination function (DCF), Designated intermediate system (DIS), 375 100 Designated Router (DR), 370–71 Distribution trees, 409 Destination hosts, 229, 231 branches, 410 DHCPv6, 479–80 leaves, 409 operation, 480 See also Multicast reasons for use, 479 DIX Ethernet, 87 router advertisements and, 479–80 DMZ, 708–10 servers, 480 dual firewalls with, 709, 710 See also Dynamic Host Configuration multiple protection types, 709 Protocol (DHCP) servers, 709 Dialog controllers, 41 uses, 708 Differentiate Services Code Point (DSCP), See also Firewalls 169, 170 DNS and BIND (Liu), 506 Diffie-Hellman, 643 DNSSec, 489, 496–97 pocket calculator, 643–44 design, 497 SSL use, 599 encryption and, 497 Digital signatures, 594, 598 specifications, 497 Digital signature standard (DSS), 642 See also Domain Name System (DNS) Digital subscriber line (DSL), 7–8, 85 Domain Internet Groper (dig), 497–98, access multiplexer DSLAM, 79, 93–94, 95 504 ADSL, 95 feature bloat, 505 encapsulation, 93–94 Domain Name Space evolution of, 90–96 resource records, 489 forms of, 94–96 root, 502 HDSL, 95 Domain Name System (DNS), 60, 483–507 as ISDN extension, 94 in action, 498–506 ISDN (IDSL), 95 authoritative servers, 487 links, 7, 78–81 basics, 486–89 link setup screen, 80 BIND, 497 Lite (G.Lite), 95 cache poisoning, 497 modulation techniques, 94 clients, 463 PPP and, 86, 91–92 concepts, 489–90 protocol stacks, 94 correct functioning, 483 router log table, 81 delegation, 491–93 routers, 78, 79, 329 dig, 497–98, 504 symmetric (SDSL), 95 entry update, 463 types of, 95 glue records, 493 VDSL, 85, 95 hierarchy, 486–87 xDSL, 94 hosts, adding, 490
- 774 Index Domain Name System (DNS) (cont’d) host direction to, 213 host utility, 498 Illustrated Network, 460–61 Illustrated Network, 484–85 message flow, 477 iterative queries, 491 message format, 476 local, 491, 492 messages, 465, 466 message format, 495 message types, 477–78 message header, 496 multicast, 266 name servers, 489, 491 network use, 466–68 nonauthoritative servers, 487 offer message details, 467 nslookup utility, 497, 501 operation, 475–78 in practice, 493–98 options field, 476 public, 527 relay agent, 464–65 query message, 495 routers and, 479–80 records, 499 sequence of messages, 477 recursive queries, 490–91 server configuration, 462–64 referral, 491–93 servers, 480 resolver, 491 Windows configuration for, 464 resource records (RRs), 493–95 See also DHCPv6 response message, 495 Dynamic IP address assignment, 121 Security (DNSSec), 489, 496–97 Dynamic link libraries (DLLs), 309, 310 server log and reply, 500 Dynamic ports, 264, 271, 272 servers, 463, 486–87 Dynamic Web pages, 573 service providers, 493 spoofing, 638 E theory, 489–93 ECN Congestion Explicit (ECT-CE), 169 tools, 497–98 Edge routers, 329, 334 Dotted decimal notation, 119 Egress routers, 446, 451–52 Double Encryption, 666 Electronic Industries Association Downstream interface, 409 (EIA), 17 DRAM, as working storage, 245 Email, 535–57 DSL. See Digital subscriber line access and reading, 541–42 Dual protocol stacks, 252 architectures, 538–47 Duplex mode, 32 clients, 538 Dynamic Delegation Discovery System delivery of, 541 (DDDS), 569 evolution, 544 Dynamic Host Configuration Protocol headers and, 552–55 (DHCP), 79, 121, 207, 233, 459–81 home office, 555 addresses on LAN2, 465–66 Illustrated Network, 536–37 addressing and, 462–68 Internet illustration, 539 BOOTP message comparison, 481 MAA, 538 BOOTP relay agent use, 475 mailboxes, 538 design functions, 475 message composition, 541 DHCPACK messages, 478 MTA, 538, 543 DHCPDECLINE messages, 477 POP3 access, 550–52 DHCPDISCOVER messages, 477 processing, 541 DHCPINFORM messages, 478 protocols, 542–44 DHCPNAK messages, 478 sending, 540–42 DHCPOFFER messages, 477 submission of, 541 DHCPRELEASE messages, 478 Embedded RP, 415 DHCPREQUEST messages, 477 Encapsulating security payload (ESP), 713, discover message details, 467 725–28 with dynamic IP addresses, 493 ESP Authentication Data field, 728 flags field, 476 fields, 726–28
- Index 775 header, 725 MIB, 621, 622 IPv4 packet formats, 727 traffic display, 74–76 IPv6 packet formats, 726 transparent bridging, 63 Next Header field, 728 Ethernet II, 88 Padding field, 728 Experimental RFCs, 20 Pad Length field, 728 Explicit-Congestion-Notification Capable Payload Data field, 726 Transport (ECT), 169 Sequence Number field, 726 Extensible MIB, 622 SPI field, 726 Extension Headers, 184 Encapsulation, 24, 28–29 Exterior BGP (EBGP), 382, 389–90 DSL, 93–94 NLRI, 391 flow, 29 sessions, 389 sequence, 253 See also Border Gateway Protocol wireless LANs, 82 (BGP) Encoding Exterior Gateway Protocol (EGP), 386 base64, 545 border routers, 387 chunked, 573 Internet and, 386–87 MIME, 548–49 External Data Representation (XDR) Encryption, 598 standard, 531 double, 666 P2TP, 667 F public key, 595–98 Fast packet switching, 435 End systems, 6, 26 Fastream NETfile FTP server, 516 End-to-end headers, 576 Federal Communications Commission End-to-end protocols, 570 (FCC), 18 Enhanced IGRP (EIGRP), 355, 364–65 Fiber Distributed Data Interface (FDDI), 85 as hybrid routing protocol, 365 File transfer as IGRP redesign, 364 Ethereal capture, 13 Enterprise-specific trap type, 626 FTP commands for, 529 Entities, 14 FTP for, 512, 526 Error control, 40 with GUI, 11 Error correction, 15 to routers, 10–11 Error detection, 15 types, 526 Error messages, 177, 199 for user information, 530 all-0 unused byte, 198 File Transfer Protocol (FTP), 10, 43, 59, ICMP destination unreachable codes, 509–31 200 active mode, 509, 525 ICMPv6, 209 anonymous, 519 list of, 200 application-level operation, 513 See also ICMP messages basics, 518–19 Ethereal, 13, 74 block mode, 527 capture summary, 50 CLI, 529 graphical interface, 75 client implementations, 513 IPv6 traffic display, 152 client process, 304 protocol hierarchy statistics, 51 client programs, 519 Ethernet, 71, 87 client software, 529 DIX, 87 CLI versions, 512 evolution, 86–90 commands, 519–21, 527–31 frames, 74, 76, 79 commercial implementations, 530 frame structure, 88 compressed mode, 527 interface, manual configuration, 330 control connection, 518, 521, 522, 523 LAN switches, 9, 33 conversation, 521 links, 72–73 data connection, 521, 522, 523
- 776 Index File Transfer Protocol (cont’d) TCP, 292–94 data transfers, 521–24 UDP, 274–75 features, 514 Forwarding, 217, 237–57 file-structure, 526 hardware-based, 243 file transfer types, 526 Illustrated Network, 238–39 FreeBSD, 512 Linux, 243 GUI implementations, 529, 530 reverse-path, 411–13 GUIs and, 516–27 software-based, 243 Illustrated Network, 510–11 Forwarding tables, 217, 220, 246, 330 Linux and, 514 location, 247 model, 521 longest match, 250 passive command, 513 lookups, 249–51 passive mode, 509, 513, 525 Fragmentation, 36, 168 passive with FreeBSD, 515 example, 177–82 passive with Linux, 515 fields, 176, 179 ports, 518 IPv4 and, 172–77 record-structure, 527 IPv6 and, 184–86 remote access for, 10 path MTU determination and, 176–77 reply codes, 520–21 as processor intensive, 176 RFCs, 518 reassembly and, 176 servers, 304, 519 Fragmentation Header fields, 186 sessions, 297, 520 Frame addressing, 82 sockets applied to, 305 Frame relay, 71, 85, 159, 434, 435–38 SONET, 32 frames, 437 SSH and, 647 problems, 438 stream mode with file-structure, 527 today, 438 stream mode with record-structure, 527 as X.25 on steroids, 436 TCP and, 296–98 Frames, 74 TFTP comparison, 472–73 beacon, 99 three-way handshake, 297 Ethernet, 74, 76, 79 transmission mode, 527 filtering, 63 Web browsers and, 516, 517, 518 flooding, 63 FileZilla, 516, 517 forwarding, 63 Firewalls, 664, 697–711 frame relay, 437 appliance general architecture, 707 hop-by-hop forwarding, 34 appliances, 700, 705 IEEE 802.3, 88 application proxy, 706 link layer and, 83–84, 204 dedicated, 697 multicast and, 420–21 design advantages/disadvantages, 710 PPP, 93 DMZ, 708–10 SONET, 32, 97 functions, 700–705 T1, 32 hardware, 700, 705 types, 83–84 ICMP messages and, 195 Frame tagging, 66 Illustrated Network, 698–99 VLAN, 66–68, 671 packet filters, 700–701, 706 FreeBSD as router packet filter, 700–701 flags, 223 software, 700, 705 FTP, 512, 515 stateful inspection, 701–5, 706–8 routing tables and, 329–30 types of, 705–10 servers, 498 Flow caching, 124 FTP. See File Transfer Protocol Flow control, 40, 274 FTP commands, 519–21, 527–31 confusion, 275 client implementation, 528 implementation, 292 for file server access, 528
- Index 777 for file transfer, 529 fields, 552–53 for remote server file management, 528 message path, 554–55 for transfer parameters, 529 Headers, HTTP, 576–77 See also File transfer protocol (FTP) entity headers, 579–80 Full-duplex mode, 32 general, 577 Fully qualified domain names (FQDNs), 486 Last-Modified, 580 request, 577–78 G response headers, 578–79 Gateways, 7, 8, 222, 329 See also Hypertext Transfer Protocol default, 233 (HTTP) residential, 78 Hidden terminal problem, 100, 101 See also Routers High-level Data Link Control (HDLC), 436 Generic Routing Encapsulation (GRE), 662 High-speed DSL (HDSL), 95 interfaces, 241 Home office email, 555 tunnels, 255 Hop-by-hop forwarding, 34 Generic top-level domains (GLTD), 502 Hop-by-hop headers, 576–77 Gigabit Ethernet (GE), 61, 87 Hosts, 6 frames, 89 addresses, 121 links, 7, 67 bridges connecting, 64 Gigabit Ethernet Passive Optical Network dead, 213 (GE-PONS), 85–86 destination, 229, 231 Glue records, 493 Linux, 224 Graphical user interface (GUI), 11–12 multicast, 415 example use, 11–12 NICs, 231 file transfer with, 11 routing tables, 222–26, 328–32 FTP and, 516–27 source, 229 Groups, multicast, 410 in TCP/IP networks, 14 Windows, 224 H Host-to-host tunnels, 253, 254 H.323 standard, 749–50 Host-to-router tunnels, 253, 254 signaling stack, 749 Host utility, 498 support, 750 Hypertext Markup Language (HTML), 559, zone components, 750 570 Half-duplex mode, 32 Hypertext Transfer Protocol (HTTP), 42, 60, Handshaking, 15 547, 559–83 Hardware addresses, 118 Apache capture, 564 Hardware-based fabric, 246 caching/proxying support, 571 Hardware-based forwarding, 243 capture, 563 routers, 247 chunked encoding, 573 switching fabric, 246, 247 commands, 575 See also Forwarding content negotiation, 571 Hardware firewalls, 700, 705 end-to-end headers, 576 Headers entity headers, 579–80 chained, 124 evolution of, 570–71 end-to-end, 576 exchange, 562 hop-by-hop, 576–77 general headers, 577 pseudo, 266–69, 297 generic message format, 572 UDP, 267–68 headers, 573, 576–77 See also IPv4 packet headers; IPv6 packet hop-by-hop headers, 576–77 headers; TCP headers HTTP 0.9, 569, 570 Headers, email HTTP 1.0, 569–70 added after email creation, 554 HTTP 1.1, 570, 571 characteristics, 552–53 Illustrated Network, 560–61
- 778 Index Hypertext Transfer Protocol (cont’d) message formats, 209 methods, 575–76 messages, 209–11 model, 571–72 multicast packets, 428 multiple host name support, 571 neighbor discovery, 211–12 partial resource selection, 571 Neighbor Solicitation messages, 213 persistent connections, 571 Packet Too Big message, 210 pipelining, 571 Parameter Problem message, 211 request headers, 577–78 Time Exceeded message, 210 request message, 574 IEEE 802.11, 98–104 requests, 573–75 CRC frame, 103 response headers, 578–79 duration byte, 103 response message, 574 frame, 102–4 responses, 573–75 frame control, 102, 103 security, 571 frame structure, 102 status codes, 576 IBSS, 98 MAC addresses, 103–4 I MAC layer protocol, 100–101 ICMP messages, 57 MAU, 87 alternate host address, 203 payload field, 103 Checksum field, 198 sequence control field, 103 Code field, 197–98 SSID, 99 codes, 198–203 variations, 87 Destination Unreachable, 198 Wi-Fi, 98–100 Echo reply, 196 IEEE 802.3, 84, 87 Echo request, 193 compliant-hardware, 90 error, 177, 198, 199–201 CSMA/CD frame, 88 fields, 197–98 IEEE 802.3ae, 88 firewalls and, 195 MAU, 87 format, 196–203 IEEE 1394, 85 format illustration, 197 IGPs. See Interior gateway protocols IPv4 packets carrying, 193 Illustrated Network, 7–14 must be sent, 204 ARP, 144–45 must not be sent, 204 BGP, 380–81 in path MTU discovery, 206–8 connections, 72–73, 74–84 presence of, 204 DHCP, 460–61 query, 201–2 DNS, 484–85 router advertisement, 203 DSL link display, 78–81 sending, 203–4 email, 536–37 solicitation, 203 firewalls, 698–99 suite, 198 forwarding, 238–39 traceroute, 203 frames and link layer, 83–84 Type field, 197 FTP, 510–11 types, 198–203 ICMP, 190–91 See also Internet Control Message internetworking, 48–49 Protocol (ICMP) IP addressing, 110–11 ICMPv4, 208 IPSec, 714–15 ICMPv6, 152, 153, 196, 208–13 IPv4/IPv6 headers, 166–67 autoconfiguration, 211–12 MPLS, 432–33 changes, 208–9 multicast, 404–5 Destination Unreachable message, 210 NAT, 682–83 Echo Request and Reply messages, 211 protocol stacks, 50–51 error messages, 209 routers, 9, 346–47
CÓ THỂ BẠN MUỐN DOWNLOAD
Chịu trách nhiệm nội dung:
Nguyễn Công Hà - Giám đốc Công ty TNHH TÀI LIỆU TRỰC TUYẾN VI NA
LIÊN HỆ
Địa chỉ: P402, 54A Nơ Trang Long, Phường 14, Q.Bình Thạnh, TP.HCM
Hotline: 093 303 0098
Email: support@tailieu.vn