32.973.26-018.2.75 36 681.3.07 "" , .. .. "" info@williamspublishing.com, http://www.williamspublishing.com 36 , , -, .

:

Internet, 2- . : . . . : "", 2001. 448 . : . . . . ISBN 5-8459-0188- (.) Internet. , Internet . Internet (Border Gateway Protocol BGP). . Internet (.. Internet), , TCP/IP. 32.973.26-018.2.75 . , , , Cisco Press. Authorized translation from the English language edition published by Cisco Press, Copyright 2000 All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage retrieval system, without permission from the Publisher. Russian language edition published by Williams Publishing House according to the Agreement with R&I Enterprises International, Copyright 2001 ISBN 5-8459-0188- (.) 2001 ISBN 1-57S70-23VX (.) "". Cisco Press. 2000

(Sam Halabi) Internet. - Marketing at an IP networking startup, IP- Cisco Systems. IP-. Optical Internetworking Forum MPLS Forum. - (Danny McPherson) Amber Networks. - Internet (Qwest, GTE Internetworking, Genuity internetMCI). , , . Internet Engineering Task Force (IETF), .. Internet. Internet .

(Alexei Roudnev) Genesys Labs/Alcatel -, . 10 "" - - Internet . , 9 UNIX. (Abha Ahuja) -- Internap Network Services, . Merit Network ( ) IP- - (Route Server Next Generation project) Internet (Internet Performance Measurement and Analysis project IPMA). , , , . .

-: (Heather) (Courtney) (Ashli). .

(Abha Ahuja), (Shane Amante), (Johnson Liu), (Alvaro Retana) (Alexei Roudnev) , . (Henk Smit), (Bruce Cole), (Enke Chen), (Srihari Ramachandra), (Rex Phernando), (Satinder Singh) (Ravi Chandra), Cisco "BGP Coders" , 2- . Amber Networks Qwest Communications, -. , (Christopher Cleveland),

(Tracy Hughes), (Marc Fowler), (Gayle Johnson) Cisco Press .

____________________________________ 13______________________________________________________________13 _______________________________________________13 ___________________________________________14 _______________________________________________________15 , ____________________________________15 , _____________________________________15 , ____________________________________16

I. Internet _________________ 18 1. Internet ______________________________20 Internet ________________________________________20 ARPANET NSFNET ______________________________________________________________ 21 Internet _____________________________________________________________________ 23 NSFNET________________________________________________________________ 24

_________________________________________________24 NAP? ____________________________________________________________________ NAP ________________________________________________ __________________________________________________ __________________________________________________ NAP ___________________________________________________________ NAP _____________________________________ ____________________________________________________ 25 25 26 26 27 27 28

________________________31 NSFNET _______________________________________________ 34

NIS_______________________________________________________35 _____________________________________________________ 35 InterNIC ___________________________________________________________________ 36

_______________________________________36 ________________________________________________________________ 37 NIC ______________________________________________________________ 37

Internet _________________________________________38 Internet_______________________________________________ ____________________________________________ - __________________________________ Internet _____________________________________________________ 38 38 39 39

Internet _________________________________________40 "Internet " _____________________________________________ 40 Internet2 ____________________________________________________________________ 42 Abilene _____________________________________________________________________ 42

_____________________________________________________43 ___________________________________________44 ____________________________________________________________44

2. , Internet _____________________________________________47, Internet ____________________________47 Internet ___________________________________________________ Internet Frame Relay ATM _________________________________ _____________________________________________ __________________________________________________________ 47 48 49 49 7

__________________________________________________________________ 50 __________________________________________________________ 50 , Internet _____________________________________ 51

ISP, _____________________________________________________52 , ISP ___________________________________________________ ____________________________________________________ ISP ____________________________________________ ___________________________________________________________________ 52 52 53 57

_____________________________________________________60 ___________________________________________60

3. I _______63 Internet __________________________63 IP-_________________________________________________________________ 63

IP ____________________65 ______________________________________________________ 67

IP _________________________________69 IP- _____________________________________________________________ ______________________________________________ ________________________________________ IP 6 _________________________________________________________________________ _____________________________________________________ 70 71 81 84 85

_____________________________________________________87 : __________________________________________88 ____________________________________________________________89

II. ____ 91 4. _______________93 __________________________93 ____________________________________________________ 94

_________________________________95- _____________________________________ 96 _____________________________ 98

______________________________100 , _____100 ________________________________________________________________101

____________________________________________________105 __________________________________________106 ___________________________________________________________107

5. Border Gateway Protocol 4 __________________________________________________109 BGP __________________________________________________110 BGP ____________________________________________112 BGP- ____________________________________________________112 ___________________________________________________________114 NOTIFICATION____________________________________________________________116 KEEPALIVE_______________________________________________________________117 UPDATE __________________________________________117

BGP ______________________________122 BGP_____________________________123 TCP MD5____________________________________124 ____________________________________________________125 __________________________________________125 ___________________________________________________________126 8

III. /I_________________________________ 127 6. BGP_________________________129 ____129 _____________________________________________________130 IP- ________________________________________________________________131 BGP__________________________________________________________132 BGP AS __________________________________________________________132 AS _____________________________________________________________133

____________________________________135 BGP ______________________________________________135

_________________136 ORIGIN___________________________________________________________138 : _________________________139

: " " ________________________________140 ___________________________142BGP-: __________________________________________________143 BGP ____________________________________________143

, ________________________________144 ________________________________________________144 , ____________________________________________144 BGP ______________________________________________________146

BGP ______________________________________147 BGP __________________________________________________________147

___________________________________________________157 ________________________________________157 _____________________158 next-hop-self ________________________159 AS ____________________________________________________________160 AS_PATH ____________________________________________161 AS_PATH ______________________________________________________162

_______________________163 _______________________________________________________164

_________________________________167 BGP-4 _________________________________________________172 ___________172 __________________________173 __________174 _____________________________________175 __________________________________________175 ___176

____________________________________________________176 __________________________________________177 ___________________________________________________________179

7. , _181 _____________________________________________________181 ________________________________181 ________________________________182 , __________________________________182 __________________________________________________183

________________________________________________________187 ____________________________________________187 , _____________________________________________________________188 1: ___________________________________________________189 2: ________________________________190 3: __________________________197 9

: _________________________________________________________________198 4: ________201 5: ____204

____________________________________________________207 __________________________________________208 ___________________________________________________________209

8. __211 , BGP, BGP______________________________211 BGP IGP__________________________________________________________211 AS _____________________________________________212

BGP _________________________________________________________________213 AS: BGP __________________________________________________________________________214 AS: BGP____________________218

_________________________________________220 ___________________________________220 _________________221 _____________________________________________________________________222

________________________222 ____________________________________________________224 __________________________________________224

9. ________________________________________________227 _____________________________________________227 ___________________________229 AS ___230

__________________231 _______________________________234

_____________________________________________________236 ____________________________________________________________237 BGP ______________________________238 ________________________________________________239 __________________________________________239

IGP- _______________________________240 AS , IBGP ________________________241 AS , EBGP ________________________243

____________________________________________________245 __________________________________________245 ___________________________________________________________246

10. TCP/IP___249 Internet _________________________249 IGP_________________________________________________________________249 _______________________________________________________________250 ____________________________________________________250 __________________________________________________250 ________________________________________________________251 _________________________________________251 _________________________________________________________________252 _________________________________________________________252

BGP __________________________252 ________________________________253 BGP _________________________________________________________253 ________________________________________________________________253 10

____________________________________________________257 __________________________________________257

IV. TCP/IP_________________________________ 258 11. BGP _____261 _____________261 ________________________________________266 BGP- ______________________________________________________________267

__________________________________________________268 NLRI ______________________________270 AS_PATH __________________272

____________________________________273 ____________________________________275 BGP ______________________________________________276 BGP ______________________________________________281

(" ") ________________________________281 NEXT_HOP_________________________________________________________________285 AS_PATH __________________________________________________________________286 LOCAL_PREF_______________________________________________________________289 MULTU_EXIT_DISC__________________________________________________________290 COMMUNITY _______________________________________________________________293

BGP-4 _________________________________________________294 , ______________295 ______________________________________297 __________301 ___________________________________________304 __________________________________________307 __309

____________________________________________________310

12. Internet ___________________________________________________313, _____________________313 _________________________________________________313 __________________________________________________315 ___________________________________317 : _____320 _______________________________328 _______________________________331 ___________________________333

__________________________________337 BGP _______340

_________________________________________351 _____________________________________________354 _____________________________________________________357 _____________361 BGP ___________________________________________________________362 ________________________362 _________________________362 BGP- __________________________________________________________365

BGP ________________________________________________________366 _______________________________________________367 ____________________________________________________370

V. _________________________ 372 11

. BGP _______________373 . ___________381, Internet _______________________381 _____________________381 _____________________________________382 ____________________________________________________________382 TCP/IP ___________________________________________________________382 ___________________________________________________382

, Internet (Request for Comments RFC) _____________________________________________________________383

. BGP- (Outbound Route Filter ORF) ________________________________________387 BGP ORF _____________________________387 _____________________________________________________388 BGP ORF ________________________________________________388 BGP ORF __________________________________________________388 ___________________388

EXEC ____________________________________________________389 __________________389 , ______________________________389 BGP- _________________________390

__________________________________________390

. BGP (Multiprotocol BGP MBGP) ________________________________391 _______________391 __________________________________________392

activate ___________________________________________________________394 ______________________________________________________________________394 AF __________________________________________________________________________394

network ___________________________________________________________395 ______________________________________________________________________395 AF __________________________________________________________________________395

____________________________________396 ______________________________________________________________________396 AF __________________________________________________________________________396

__________________________________________________396 ______________________________________________________________________397 AF __________________________________________________________________________397

___________________________________________________398 ______________________________________________________________________398 AF __________________________________________________________________________398

_____________________________________________399 ______________________________________________________________________399 AF __________________________________________________________________________399

______________________________________________________400 ______________________________________________________________________400 AF __________________________________________________________________________400

BGP ________________________________________________400 AF ___________________________________402 ___________________________________________________________402

12

Internet, 60- XX , , . ARPANET NSFnet, ANYBODYSNET ( : " " . .). , Internet , , , . Internet . . , , . , , , , . /I, , . , , . , , , . , , , . , BGP, Internet, .

, , Internet. , Internet:, , Internet. , , , . , Internet (.. - Internet), , /I.

, Internet. - Internet , , Internet. , , . , , 13

. , . /I. "" , .

. I. Internet ( 13 Internet. , - , Internet. Internet, 1, (Network Access Points), Internet (Router Arbiter project) (Network Information Services). , Internet. 2 , Internet. , Internet , , , , , . 3 (Classless InterDomain Routing - CIDR.), (variablelength subnet masks VLSM), Iv6 /I ( Internet). II. . 5 6 : , , ; . (Border Gateway Protocol - BGP), Internet. BGP. III. /I. 610 BGP. BGP, 2. BGP , . , , . IV. /I. 11 12 . , , . , , 11 12. " ". , . , , , Cisco IOS BGP IOS, 14

BGP.

. , . , . . , , Cisco IOS, . , . , - . , . . , , , () . . , , , . , , , , , .

, . . , : , , 11 12; () .

, Cisco IOS. Cisco IOS . (I) . ([ ]) . ({ }) . , ([{}]), 15

. , . (, , ) , (, show). , .

,

:

: 16

17

I. Internet ... 1. Internet 2. , Internet 3. I- -/I Internet. , , Internet . 1 , (Router Arbiter project), (Network Access Point) (Network Information Services). , . 2 , Internet. 3 /I, Internet, , I-.

1. Internet

18

: Internet. , Internet, Internet 40 . (National Science Foundation NSF) (Network Access Points NAP). Internet ( , (NAP)). , , Internet NAP, NAP . (NAP) Internet. ( , NAP.). (Routing Arbiter project). , : (Routing Arbiter Database). NAP, Internet TCP/IP. . . . , (National Science Foundation NSF) Internet: InterNlC, , , NIC. Internet (Internetworking Routing Registies). Internet. , Internet: " " (The Next-Generation Initiative), Internet2 Abilene.

1. Internet

19

1. Internet Internet . Internet . Internet Internet .

Internet Internet 60- XX , (Advanced Research Projects Agency ARPA, DARPA), (Department of Defense). DARPA , , , . 1969 , 56 /. , , : MILNET MINET . ARPANET ( ), "ARPA Internet" Internet. . 1.1 1.2 ARPANET ( 1969 1976 ). , , ARPANET, , Internet. ARPANET , ( Acceptable Usage Policy AUP). , ARPANET . ARPANET , . (National Science Foundation NSF) NSFNET2. ARPANET 1989 .

1. Internet

20

. 1.1. ARPANET ( 1969 .)

. 1.2. ARPANET ( 1976.)

ARPANET NSFNET 1985 ARPANET , . , NSF NSFNET. NSFNET ( NASA Science Network), , NSFNET. (1986 ) NSFNET 1. Internet 21

. , , , , . 1988 , 56 /, 1 (1,544 /). , NSF, Merit Network, Inc. MCI, IBM . , NSFNET 1 13 Merit, BARNET, MidNet, Westnet, NorthWestNet, SESQUINET, SURAnet, (National Center for Atmospheric Research NCAR) NSF. 1990 , , Merit3 , IBM MCI Advanced Network and Services (ANS). Merit , , NSFNET, a ANS (Network Operation Center NOC). 1991 , (45 /). . 1.3 NSFNET .

. 1.3. NSFNET 90- NSFNET - . . ( , ). , Internet- (Internet Service Provider ISP) , . . . (Federal Internet eXchange points FIX), . (Commercial Internet eXchange points CIX), . Internet , , 1. Internet 22

, . - , NSF Sprint (International Connection Manager ICM), , . 1995 NSFNET.

Internet NSFNET , , . Internet ( NSFNET) , , UUNET, Qwest, Sprint . . . 1.4 Internet.

. 1.4. Internet Internet Internet, , (Points Of Presence POP). , . Internet , POP . Internet ( . .). , Internet, 2, ", Internet ". , , (national provider). , , (regional provider). . , (Network Access Points -NAP) . - Internet (Internet Service Provider ISP) , Internet . - (Network Service ProviderNSP) , 1. Internet 23

. NSP , NAP .

NSFNET NSF 1986 . , (High Performance Computing and Communications Program HPCC), . (National Research and Education Network NREN) 90- 1 /. , 1995 NSFNET Backbone Network Services, NSF NSFNET. NSF 1987 ( 1993 . 3). 1992 NSF -, . NSF . NSF (NSF 93-52) 1993 . , : (NAP), . (Routing Arbiter project RA), , NAP. (very high-speed Backbone Network Service vBNS), . NSP, , , NAP NAP. NSP NAP. , NSF .

(Network Access Points NAP) , , NAP, vBNS . NAP , -, . , 1. Internet 24

NSF (NSF Acceptable Usage Policy), Internet . , - , , .

NAP? NSF, (NAP) , . NAP 100 / . NAP , - (45+ /) FDDI (100 /). NAP FIX CIX ( , ), FDDI 45 /. NAP , .. . NAP , . NSF NAP: Sprint NAP ( -); PacoBell NAP - ( ); Ameritech Advanced Data Services (AADS) NAP ( ); MFS Datanet (MAE-East) NAP ( ). NSFNET 13 1994 Sprint NAP. 1994 NAP PacoBell, 1995 NAP Ameritech. , , 25 1995 , MFS ( MCI Worldcom), NSFNET MAE-East FDDI. NAP , (.. 1,5 /), , . NSF NAP IP, CLNP (Connectionless Networking Protocol). CLNP- , IDRP (Inter-Domain Routing Protocol) (ISO OSI Exterior Gateway Protocol EGP), , NAP.

NAP NAP NAP. : NAP vBNS . , - NAP. NAP . , 1. Internet 25

NAP, (Routing Arbiter RA), vBNS, (Quality of Service QoS) . NAP, , NAP . NAP NAP. NAP .

ARPANET NSFNET FIXEast (-, ) FIX-West (NASA AMES, , ) (Federal Internet eXchange FIX). , , . . Commercial Internet eXchange points (CIX). 1996 FIX-East. FIX-West .

(Commercial Internet eXchange CIX ( "" . .} -, , . CIX FIX , . , CIX , , . , CIX. , . IX . , CIX . , CIX, : , . , . CIX Internet , NAP, , . CIX Web- www.cix.org. 1. Internet 26

NAP NAP FDDI-, ATM- Ethernet- ( Ethernet, Fast Ethernet Gigabit Ethernet). NAP FDDI Gigabit Ethernet DS3, ATM. . 1.5 NAP. , Internet , NAP. NAP , , NAP.

. 1.5. NAP

NAP Internet , NAP. , NAP . NAP . , Internet , NAP, , . Internet , . NAP. . NAP, Internet 1. Internet 27

. . , , . , . NAP , . , , , , , NAP. , . - . . , LEG (local exchange carriers) IXC (interexchange carriers). , NAP , .

NSF (Routing Arbiter RA project), . , RA, , Internet. , NAP, , . RA . " ". , (Route Server). , . . 1.6 . RA . Internet. ; G, , . , . (Automomous System AS) 1. Internet 28

Exterior Gateway Protocol (EGP), , Border Gateway Protocol (BGP) IDRP ( IP CLNP). , NAP, vBNS, . (Quality of Service QoS) .

. 1.6. , .. , (type of service) , , Internet. , . Internet. RA Merit Network, Inc., (University of Southern California Information Sciences Institute USC ISI), Cisco Systems ( ISI) (University of Michigan ROC) ( Merit ). RA . (Route Server RS) RS Sun, NAP. , NAP, . , (RIPE 181). - -. . , " ", (n-1) 1, . 1. Internet 29

( ). (Network Management System) , RS. RS - , RS. Merit (Merit Routing Operations Center) (central network management station CNMS), . (Routing Arbiter Database RADB) , Internet (Internet Routing Registry IRR). RADB , RIPE-181, RIPE (RIPE Network Coordination Center RCC). RADB Policy Routing Database (PRDB). PRDB 1986 NSFNET. 1995 , RIPE-181 , , , RADB. (Routing Engineering Team) , NAP. , , .

, , . , RADB. RADB NAP. RADB . RIPE-181. IRR Routing Policy Specification Language (RPSL). RPSL IRR. Routing Policy Specification (RPS) Working Group, Internet Engineering Task Force (IETF)8. RFC 2622 , RFC 2650, USC ISI. RPSL RIPE-181, RPSL ( RFC 2650 " RPSL "). RIPE-181 RPSL . RPSL , . RPSL . - , , RIPE-181 RPSL. 1. Internet 30

, . , , , . , NAP. To . " " . , NAP, , , , . 1998 Merit . Merit RA RA. NSF, Merit ISI RA Route Server Next Generation (RSng), Merit . NAP , Internet . 1997 Merit NSF Internet Internet Performance Measurement and Analysis (IPMA). IPMA Internet. , IPMA , . North American Network Operators Group (NANOG) NSF NSFNET RA. , , NSFNET. , , Merit. NANOG , . , RADB Internet Internet. Internet . , , Internet.

(very highspeed Backbone Network Service vBNS) 1. Internet 31

(Supercomputer Centers SCC). 24 1995 MCI NSF vBNS. MCI : 155 / , IP CLNP NAP, NSFNET; ; NAP RA; ; , NSF. 50 , 5 , MCI NSFNET , NSF: (Cornell Theory Center ) ( ); (National Center for Atmospheric Research NCAR) ( ); (National Center for SuperComputing Applications NCSA) ; (Pittsburg SuperComputing Center PSC): - (San Diego Supercomputer Center SDSC). vBNS XXI . , (Asyncronous Transfer Mode ATM) (Syncronous Optical Network SONET) , . NSF vBNS , (, NCAR). . , NCSA , . vBNS NAP, -, , . . 1.7 NAP . , vBNS 12, , Juniper Networks Cisco Systems. 48 Juniper 1999 .

1. Internet

32

. 1.7. vBNS MCIWORLDCOM. 2000. . , NCR 931047. , , (National Science Foundation).

vBNS , . NSFNET. vBNS TCP/IP, "" . NSFNET 1995 . vBNS SCC 80 , DS3 12. IPv6 ( IP 6 . .), MPLS. 2000 NSF MCI WorldCom vBNS, 2000 . vBNS (Acceptable Use Policy AUP), . , . QoS vBNS (very high-performance Backbone Network Service). 1. Internet 33

, vBNS , NSFNET.

NSFNET Internet NSF , ( (mid-level networks)) NSFNET . NSFNET . (Regional Network Provider RNP) (, ), (Inter-Regional Connectivity IRC). NSF 93-52 RNP. NAP NSP. - InterNIC NSFNET (NSFNET Information Services Manager). , .' , NAP, RA, vBNS . , . ( NSP) , , . . NSFNET ISP, NSF NAP, , NAP. NSF , 1 ( NAP RA (NAP Manager/RA Cooperative Agreement), .. ). . 1.1 NSFNET Internet. , MCInet ( Cable & Wireless) Sprintlink. 1995 Internet .

1.1. ArgoneBARRnet

CA*net CERFnet CICnet Cornell Theory Center 1. Internet

Internet CICnet MCInet MCInet CERFnet MCInet MCInet34

CSUnet DARPA JvNCnet MOREnet NEARnet NevadaNet SESQUiNET SURAnet THEnet Westnet

MCInet ANSnet MCInet Sprintlink MCInet Sprintlink MCInet MCInet MCInet Sprintlink

NIS NSF , . NSFNET (Network Information Services NIS). . , . , Internet. (Defense Information Systems Agency Network Information Center DISA NIC). Internet NSFNET , , (NASA Science Internet NSI) (Energy Sciences Network ESnet). , Internet, 1992 (National Research and Education Network NREN). , , NSF , NSFNET NREN .

NSF , (Network Information Services NIS). . , NSF (NSF Network Services Center NNSC). Bolt, Beranek and Newman (BBN). NSFNET, , . , , . , , NASA NSI. Internet DISA NIC, 1. Internet 35

Government Services, Inc. (GSI). NSFNET . NSFNET Merit, Inc. , NIS , . , , Merit, Inc.

InterNIC 1993 , AT&T, General Atomics Network Solutions, Inc11, (International Network Information Center InterNIC). , NSF. NSF General Atomics. AT&T (Database and Directory Services), Network Solutions (Registration and NIC Support Services).

. NIS , . NSF, AT&T . (Directory Services) ( white pages): , Internet White Pages, .500, WHOIS netfind. .500 , . WHOIS Internet WHOIS-. , , InterNIC. MIL (military) DISA NIC, InterNIC (InterNIC Registration Services server). Netfind Internet " " (white pages). (), . (Database Services): , Internet, Request For Comments (RFC), Internet Drafts (ID), IETF (IETF Meeting minutes), IETF (IETF Steering Group IESG) . , . AT&T 1. Internet 36

, . (Directory of directories): , . , , Internet. , , , , , ..

AT&T , , , . . Telnet, FTP, (E-mail) " " World Wide Web.

NIS RFC 1174, . Internet Internet (Internet Assigned Numbers Authority IANA12 ). IANA (University of California's Information Sciences Institute). IANA IP , , Internet (Internet Registry IR).

, NIS IR, IR - . , Internet, : ; ; ; . 1993 1998 , , NSI .com, .net .org. 1998 , NSI (Shared Registration System) . , , , , . . Internet (Internet Corporation for Assigned Names and Numbers ICANN). , . Internet. ICANN .

NIC 1. Internet 37

("Information Services") , General Atomics. NSI, NIC (NIC Suppot Services). , , (Network Information Center's NIC) Internet. , , InterNIC.

Internet IP- (Autonomous System AS). Internet (Regional Internet Regisrty RIR) Internet Internet (American Registry for the Internet Numbers - ARIN), (Reseaux IP Europeens Network Coordination Center RIPE NCC) - (APNIC).

Internet 1997 IANA IP- Network Solutions, Inc. ARIN. ARIN 22 1997 . ARIN IP- : . . . . ARIN IP-, (AS), IN-ADDR.ARPA IP6.INT. , , .. , , WHOIS . ARIN . IP-, ARIN.

1989 (Reseaux IP Europeens Network Coordination Center RIPE NCC RIPE) Internet . Internet. RIPE RIR. RIPE IP-, (Domain Name System DNS), IP-, DNS 1. Internet 38

IP-. , Internet, RIPE. . ARIN, RIPE .

- 1993 - (Asian Pasific Network Information Center APNIC) , ARIN. APNIC - , 62 , - , . APNIC DNS, . APNIC , , . APNIC - Internet (Asian Pasific Regional Internet Conference on Operational Technologies APRICOT), .

Internet ISP, , . ( policy , . .), , . , ISP . , , . Internet (Internet Routing Registries IRR) , , . , (routing registry RR). RR , , RR. Internet (Internet Routing Registry IRR). RR , . , , . , . (Autonomous Systems AS) 1. Internet 39

(Exterior Gateway Protocols EGP), (Border Gateway Protocol BGP). AS. , , . . RR . IRR. RIPE (RIPE Routing Registry), Internet. Cable & Wireless (Cable & Wireless Routing Registry) . CA*net CA*net (CA*net Routine Registry). Internet JPRR (Japanese Internet service providers Routing Registry). (Routing Arbiter Database). ARIN (ARIN Routing Registry). Internet , (Routing Arbiter Database RADB) ARIN, . , RADB (Routing Arbiter project). , Qwest, Level(3) Verio, RR.

Internet Internet , , , . . "" Internet. . .

"Internet " "Internet " (Next-Generation Internet NGI Initiative) , , , 1000 , . NGI, 1 1997 , : (Defense Advanced Research Projects Agency DARPA); (Department of Energy DoE); (National Aeronautics and Space Administration NASA); (National Institute of Health NIH); (National Institute of Standards 1. Internet 40

and Technology NIST); (National Science Foundation NSF). NGI , (Large-Scale Network Working Group of the Subcommittee on Computing, Information and Communications CIC R&D), (White House National Science and Technology Council's Committee on Technology). NGI : ; ; .

NGI , Internet. : ; ; ; (Quality of Service) ( ); ( ). , NGI. "100x" "1000x". "100" 100 , - . , 100 Internet . : NSF (NSF's very high-speed Backbone Network Service vBNS). NASA (NASA's Research and Educational Network NREN). (DoD's Defense Research and Education Network DREN). - (DoE's Energy Sciences network ESnet). "1000" 10 , 1000 . "1000" DARPA's SuperNet. , .

NGI : ; ; ; 1. Internet 41

; . , : ; ; ; ; ; ; .

Internet2 Internet2 Internet (University Corporation for Advanced Internet Development UCAID). 1996 34 , . , Internet2, Internet- , . Internet, , , , . Internet2 Internet. Internet2 160 50 . Internet2 , UCAID. , NSF , NGI. NSF. Internet2 Internet, , Internet2.

Abilene Abilene , UCAID. Internet2, Internet2. UCAID Qwest Communications, Nortel Networks Cisco Systems Abilene Network. Internet2 . Abilene, 1999 , 12. 48 (2,5 /) POS (Packet Over SONET). vBNS, Abilene Internet-, Abilene , Abilene. Internet2 Abilene, () , , Internet 6 (Internet Protocol version 6 IPv6) (Quality of Service 1. Internet 42

QoS). Abilene IPv6 QoS. . 1.8 Abilene.

. 1.8. Abilene

NSFNET 1995 . Internet , . , Abilene vBNS, , . Internet , , . Internet - , . , Internet. , ? ? , Internet? . . 1. Internet 43

10 , . Internet, TCP/IP.

NAP , NSF? , . , NAP. . , , , , . Internet , NAP? . NAP . - , . , NAP , . NAP ? . , . NAP. , NAP, ? , . IR IRR? Internet (Internet Registry IR), Network Solutions, Inc, Internet (.. ..). Internet (Internet Routing Registry IRR), RADB, -. (Routing Arbiter Databases) ? . ( RFC .). RADB .

1. www.darpa.mil 2. www.nsf.gov 3. www.merit.edu 4. www.ra.net 5. www.isi.edu 6.http://www.ietf.org/rfc/rfcl786.txt 7. www.merit.edu 8. www.ietf.org 9. www.nanog.org 10. www.vbns.net 11. www.internic.net 1. Internet 44

12. www.iana.org 13. www.icann.org 14. www.arin.net 15. www.ripe.net 16. www.apnic.net 17. www.ngi.gov 18. www.internet2.edu 19. www.internet2.edu/abilene

1. Internet

45

: , Internet (Internet Service Provider ISP). ISP Internet, . ISP. , ISP. ISP. ISP . . , .

2. , Internet

46

2. , Internet , , , Internet, , Internet. , Internet, -, .. "" - . ISP . ,, , , -/i pa , , , , .. Internet , . "" Internet.

, Internet' , " cefeu ; ^ . " Internet, , % . - , Internet. , , ( dial-up) , ' .

Internet , Internet 56 / 64 / 1,5 / 2 / ( 1 1, ) 45 34 / (/) 155 / () . , 2. , Internet 47

, 622 / () 2,5 / (48). , , 24 . , , , . Internet , (customer premises equipment CPE) IP- . , Cisco HDLC ( ), . . 2.1 Internet .

. 2.1. Internet no

Internet Frame Relay ATM Frame Relay ATM (Asynchronous Transfer Mode ) Internet. . Frame Relay ATM. , . Frame Relay ATM IP-, , . . 2.2 Internet Frame Relay. Internet no Frame Relay ATM , . , Internet IP- . , . Frame Relay, ATM , Frame Relay, ATM . Frame Relay ATM IP. , - , .

2. , Internet

48

. 2.2. Internet no Frame Relay Frame Relay ATM, Internet. , ( ) Internet.

56 /. ISDN (Integrated Services Digital Network) BRI (Basic Rate Interface) 128 / PRI (Primary Rate Interface) 1,5 /. , Internet. ISDN BRI PRI (.. ), , -, .

(Digital Subscriber Line DSL) Internet . . DSL , . DSL xDSL, . . 2.1 DSL . 2.1. DSL DSL 1,5 8Mbps (POTS)

ADSL (Asymetrical Digital Subscriber Line) HDSL (High-bit-rate Digital Subscriber 1,544 Mbps

16 640 Kbps

1,544 Mbps

2. , Internet

49

Line) SDSL (Symmetric Digital Subscriber Line) VDSL (Very highbit-rate Digital Subscriber Line)

2,048 Mbps 1,5 2.048 Mbps 1,6 19,2 Mbps ( . )

2,048 Mbps 1,5 2.048 Mbps

12,96 Mbps ( ( 1,4) ) 55,2 Mbps ( 300)

DSL , (Plain Old Telephone System POTS), . , DSL, ( 64 / 52 /). DSL- . 1999 DSL.

DSL, Internet . , . , ( ), . , 2 / ( ) 64 / ( ). DSL, "-", , -, . . , , . 2 , Internet , 2003 16 .

( . .) , , ( Web-). , , - (content-provider). , , (data center), Web-. , . 2. , Internet 50

Internet, Fast Ethernet (100 /) Gigabit Ethernet (1 /). Internet , . o , Ethernet. , . , , o po . , -, " " (Denial of Service DoS), , . . , , . , (Virtual Local Area Networks VLAN) " : , , " 2- ., ("Intcnvnturfions: Bridges, Routers, Switches and Internetworking Protocols", 2nd edition., Addison-Wesley, 1999) (Radia Perlman) " Cisco" ("Cisco LAN Switching", Cisco Press, 1999) (Kennedy (Lark) (Kevin Hamilton).

, Internet , , , , (Virtual Private Networks VPN) IP-. , '' "" . , , , . ISP , , , . , . . ( ). , , , .

2. , Internet

51

ISP, , , . , , , , , . , , , .

, ISP , . , . , , , Frame Relay, , -. , , , . , , , , . , , (Customer Pertinent Equipment CPE) ( ), CSU/DSU (Channel Service Unit/Data Service Unit). , . , , / . Internet . . , , , , , . , Internet. ( ), . , , Internet.

52 2. , Internet

(Service-Level Agreements/Service-Level Guarantees SLA/SLG), . , . , , . , / . , , , .

ISP ISP . . " " . . , . , ISP. . , . , .

, . , , , , . 48 . , . .

" " ISP . " " (bottlenecks), , , " ", , ( oversubscription) (Points of Presence POP) . . , , 2. , Internet 53

, .

. 2.3. ISP

, . , , 20 TI POP , , NAP 1, " ". . 2.3 5:1, .. 1 1. ( ) . , , , 8:1 10:1. , , .

. 2.4.

" " , , . , Web- , Internet 56 /, , , Internet . . 2.4 , , Internet , Web- 56 /, .. , Internet. , , 56 /, . , . . ? ? 2. , Internet 54

( ) ? ? ?

ISP

. 2.5. , . , - NAP, POP - , . , . ISP . , POP NAP , POP , . 2.5. , , .. . , , . , , . NAP . , POP. . 2.6 , . 2.7 .

2. , Internet

55

. 2.6. . . , (Mean Time Between Failures MTBF). , . (Mean Time To Repair MTTR), - , - . , .

. 2.7. 2. , Internet 56

, , IP- (IP hops), .. , , . IP-, , , . (Multiprotocol Label Switching MPLS), ATM Frame Relay. IP-, traceroufe. IP- , . , , . , , . , Internet , . AS ( ) . , , .. . - NAP . NAP, .

. Internet , ( NAP), . , , , , . 1, " Internet, , NAP . NAP, .. NAP . (Nondisclosure Agreement NDA), . , . , , , .

2. , Internet 57

, , (demarcation point DP). , ( ). , . . , - . . 2.8 .

. 2.8. - . , , , .

, (Customer Premises Equipment CPE), , CSU/DSU, (out-of-bandwidth ). . , , , . / . ISP . , , . , , . , . , . . 2.92.11 . , . 2.9, CSU/DSU CSU . , . , . 2.10 , , . . 2.11 , , . , POP , 2. , Internet 58

.

. 2.9. CSU/DSU; ()

( ) (collocation) . -, . 2.12. .

. 2.10. , CSU/DSU ()

. 2.11. (

. 2.12. () , . 2.12, (. 2.13). ISP , , .

2. , Internet

59

. 2.13. ()

, , . , , . - , , , . , , . IP- .

, ? - , . , 12 48, . , , . . , . , . " " ? , " ? "" " , . , -, , ( 2. , Internet 60

). , , , , . . , ? , , ( ;). , . . - , ? , .

2. , Internet

61

: Internet. IPv4, , , . (Variable-length subnet masks VLSM). IP. I-. IP-. , , , . (Network Address Translations - NAT). NAT ; IP. IP 6 (IPv6). (IPng), , (classless interdomain routiftg.-CIDR) IPv4.

3. I

62

3. I Internet, 4- IP (Iv4) . Internet. I-, , (Variable-Length Subnet Mask VLSM), (Classless Interdomain Routing CIDR) (Network Address Translation NAT). IP 6 (IPv6). . . Internet . I-, , , .

Internet , Internet, IP 4 (IPv4)1, , , IP. : IP-. IP2. (VLSM)3.

IP-, IP- (32-) , , , W.X.Y.Z, (, 10.0.0.1). 32 : ( ) ( ). 3. I 63

IP-. 5 IP- ( ): , , , D . . 3.1. 3.1. IP- A B C D E 0.0.0.0 127.255.255.255 128.0.0.0 191.255.255.255 192.0.0.0 223.255.255.255 224.0.0.0 239.255.255.255 240.0.0.0 255.255.255.255 0 10 110 1110 1111 7 14 21 24 16 8

, , . D , . . . 3.2. 3.2. IP-, 0.0.0.0 10.0.0.0 - 10.255.255.255 127.0.0.1 - 127.255.255.255 172.16.0.0-172.31.255.255 192.168.0.0 - 192.168.255.255 192.168.255.255 255.255.255.255 ( ) (RFC 1918) "" (RFC 1918) (RFC 1918)

, , (classful model). , . IP-. .

0 () . ( 0 7), . , ( 8 31) . 124.0.0.1. 124.0.0.0 , . (. 3.1) 128 (27) . , 0.0.0.0 , 127 (27-1) .

. 3.1. IP- , 3. I 64

. , 124.0.0.0 ( ) , (124.255.255.255) . , 16777214 (2161) , 16777216 (224).

1 0 . ( 0 15) , ( 16 31) . 16384 (214) 65534 (2162) (. 3.2). , , 172.16.0.1, 172.16.0.0 , 1 .

. 3.2.

1, 1 0 . ( 0 23) , ( 24 31) . , 2097152 (221) , 254 (282) (. 3.3). 192.11.1.1, 192.11.1.0 , 1.

. 3.3.

D D 1, 1, 1 0 IP. D IP, . , , , .

1, 1, 1 1 IP. . .

IP . , (variable-length subnet masks VLSM). (subnet subnetwork) IP- , . , IP 3. I 65

, . , IP- , , , . ( ). IP-2 , (netmask). , , IP-, . , , . , . 3.4 255.0.0.0 10.0.0.0. . IP-, , . IP- 10.0.0.1 ( 10) ( 1).

. 3.4. , , . : 255.0.0.0 . 255.255.0.0 . 255.255.255.0 . IP- . . , Ethernet, Token Ring FDDI, . , , , 10.0.0.0 , 16 , . 3.5. . . 3.6 255.255.0.0 10.0.0.0. IP- 10.0.0.1 : 10; 0; 1. 255.255.0.0 , , ( ). 10 256 10.0.0.0 10.255.0.0. 16777214 65534.

. 3.5.

3. I

66

, 10.0.0.0 . , , Cisco. "" IOS ip subnet-zero.

. 3.6.

(variable-length subnet mask VLSM) , . VLSM3 , .. . VLSM . . , , , , . , .. , , . , . , 192.214.11.0, . 100 , 50 . , 0 ( ) 255 ( ) 256 , .. 192.214.11.0 192.214.11.255. VLSM . 192.214.11.0, , 255.255.255.0 ( 1 ). 192.214.11.0 255.255.255.. , ( ) , .

1 0. , , " " , , . , . , , , . 3. I 67

. 3.3 , 256 . 3.3 C 128 1000 0000 2 192 1100 0000 4 224 1110 0000 8 240 1111 0000 16 248 1111 1000 32 252 1111 1100 64

* 128 64 32 16 8 4

* , " " .

VLSM , . 3.3. 255.255.255.128 128 255.255.255.192 64 . 100 50 .

. 3.7. ,

. 3.8. VLSM , . , 192.214.11.0. -, 255.255.255.128. 128 . 192.214.11.0 ( .0 .127) 192.214.11.128 ( .128 .255). 192.214.11.128 255.255.255.192 64 3. I 68

: 192.214.11.128 ( .128 191) 192.214.11.192 ( .192 255). . 3.7 3.8 . , . , VLSM. , 1 Routing Information Protocol (RIP-1) Interior Gateway Routing Protocol (IGRP) , , . , , , Open Shortest Path First (OSPF), IGRP (Enchanced IGRP EIGRP), 2 Routing Information Protocol (RIP-2) Intermediate System-to-Intermediate System (IS-IS), VLSM, . RIP-1 IGRP IP-, , . , IP- , . , . .

IP IP- . , . , 16 , , - , . 1991 , , . : IP- , Internet, IP-. , , Routing and Addressing (ROAD) IP (IP next generation directorate IPng). 1992 ROAD IP (classless interdo-main routing CIDR). IPng IP- IP 6 (IPv6), . . IP- . (classless interdomain routing 3. I 69

CIDR)4. () IP- Network Address Translation (NAT)5,7. IP 6 (IPv6)8 . IP- IP- . IP- IANA Internet Internet Registry (IR). IP- , Internet. , IP- IP-, , . IP- . ( -), , , , . , IP-. , , ( ), ( ), ().

IP- , . , , IP. . , , -. . 3.4 . 3.4. 256 512, 256 1024, 512 2048, 1024 4096, 2048 8192, 4096 16384, 4096

1 2 4 8 16 32 64

Internet, Internet American Registry for Internet Numbers (ARIN), . ARIN 16 4096 . . , , , ., Web 3. I 70

ARIN (www.arin.net). : , , , . . 3.5 . , , . 3.5. 61.0.0.0 61.255.255.255 62.0.0.0 62.255.255.255 63.0.0.0 63.255.255.255 64.0.0.0 64.255.255.255 128.0.0.0 191.255.255.255 192.0.0.0 192.255.255.255 193.0.0.0195.255.255.255 196.0.0.0 198.255.255.255 199.0.0.0 199.255.255.255 200.0.0.0 200.255.255.255 201.0.0.0 201.255.255.255 202.0.0.0 203.255.255.255 204.0.0.0 205.255.255.255 206.0.0.0 206.255.255.255 207.0.0.0 207.255.255.255 208.0.0.0 208.255.255.255 209.0.0.0 209.255.255.255 210.0.0.0 210.255.255.255 211.0.0.0 211.255.255.255 212.0.0.0 212.255.255.255 213.0.0.0 213.255.255.255 216.0.0.0 217.255.255.255 APNIC RIPE NCC ARIN ARIN RIPE NCC ARIN ARIN - APNIC ARIN ARIN ARIN ARIN ARIN APNIC APNIC RIPE NCC RIPE NCC ARIN

1997 1997 1997 1999 1993 1993 1993 1993 1993 1993 1993 1993 1993 1994 1995 1995 1996 1996 1996 1997 1999 1998

, . , 1991 1995 10 ; 1998 . . 3.9 Internet. , 80000 1995 . , , 2000 76000 . IP-, , (Classless Interdomain Routing CIDR). IP , . CIDR IP- , IP- , , . , 198.32.0.0 /16, 198.32.0.0/16. /16 , 16 . , IP- 198.32.0.0 255.255.0.0. 3. I 71

. 3.9. Internet * CIDR 25 2000

(supernet), , . , 198.32.1.0 255.255.255.0, /24 CIDR. 198.32.0.0 255.255.0.0 198.32.0.0/16, , (16 24), , . . 3.10 . 198.32.0.0/16 ( 198.32.0.0, 198.32.1.0, 198.32.2.0 ..) , (aggregate). , " ", '' CIDR" "" . , , IP- , . , CIDR (/), , , .

3. I

72

. 3.10. CIDR , , , -, CIDR, , . : 198.213.0.0/16 16 . 198.213.1.0/20 20 . , CIDR, (classless), , . CIDR Internet, IP- . , , , (stub network). , -, ; , , Internet. , , . IP-, , , . , , . . 3.11 . , ISP3 IP-, 198.0.0.0 198.1.255.255 (198.0.0.0/15). ISP1 ISP2. , ISP1 198.1.0.0 198.1.127.255 (198.1.0.0/17), a ISP2 198.1.128.0 198.1.255.255 (198.1.128.0/17). ISP1 ISP2 . , . 3.11 , , , CIDR: ISP1 ISP2 , , 1SP3, , . TCP/IP. . 3.11 , CIDR. , ISP1 ISP2 . ISP1 198.1.0.0/17. ISP2 198.1.128.0/17. ISP3 ISP1 ISP2 (198.0.0.0/15). , .

3. I

73

. 3.11. CIDR , , ( leaf nodes), . , , , , ( . aggregation . .} , , , ISP3, , , . , , (single-homing], IP- CIDR . , . . , IP, , . ( ) , . (multihoming). , , .

TCP/IP . , , , . , , : 3. I 74

198.32.1.0/24 1 198.32.0.0/16 2 198.32.1.1 , , , , 1. . 3.12 . : 198.32.1.0/24 198.32.0.0/16, 198.32.1.1 1.

. 3.12. - 1 , , ( 2). , , , . , , , , , .. . . 3.12, , 198.32.1.0/24, , , .. . .

() , : (routing loops) , , () . (routing loop} , , . 0.0.0.0/0, , . , . , , (bit bucket) ( Cisco NullO) . , , , .

3. I

75

. . . 3.13 ISP1 198.32.0.0/13.

. 3.13. , ISP1 Foonet ( 198.32.1.0/24) - . , ISP1 0.0.0.0/0, ISP2. , ISP1. , 198.32.1.1, , ISP1 , , , , ISP2. , ISP1 ISP2, . , ISP1 198.32.0.0/13. , , , , . , ( ) , , , " " (black holes). " " , , , , , . , .

, , (- ), . . 3. I 76

(single-homing scenario) , IP, . , , , . . , . , , , , . , . , , , , : . , , . , . "Keep It Simple, Stupid (KISS)", , , , , , .

( . 3.14) , . , , , , , . : (1SP1 ISP2) Onenet, Twonet Stubnet . . 3.6 IP, () . , Onenet Twonet ISP1 ISP2, IP- ISP1 (. 3.14).

3.6. ISP1 Onenet Stubnet Twonet ISP2 198.24.0 198.31.255.255 198.24.0.0 198.24.15.0 198.24.16.0 198.24.23.0 198.24.56.0 198.24.63.0 198.32.0.0 198.39.255.255 198.24.0.0/13 198.24.0.0/20 198.24.16.0/21 198.24.56.0/21 198.32.0.0/13 ISP1, ISP2 ISP1 ISP1, ISP2 ISP1 ISP1 ISP1

3. I

77

. 3.14. " " . , IP, . - ( - (proxy aggregation)), . , ISP2 " " . Onenet Twonet.

" " .

ISP2 , Onenet Twonet (198.24.0.0/18), . 3.14, " ". , , Stubnet, ISP1, , 198.24.0.0/18. ISP2 , Stubnet, IP-, ISP2, " ". ISP2 , IP- (198.24.0.0/20 Onenet 198.24.0.0/21 Twonet), ISP1. , ISP2 3. I 78

198.32.0.0/13.

. 3.15. " . 3.15 . , ISP2 Onenet Twonet. , Stubnet, ISP2. , ISP1 Onenet Twonet (. 3.15). ISP1 198.24.0.0/13, Onenet Twonet , .. ISP2.

, IP- , . . 3.16. Largenet IP- ISP1 ISP2. . , ISP1 198.24.0.0/13, a ISP2 198.32.0.0/13. IP-, Largenet.

3. I

79

. 3.16. IP-,

, . 3.16, . , ISP2 ISP1. ISP1 198.24.0.0/13 , Largenet, 198.24.0.0/20, , . Largenet, ISP2. 1SP2 198.32.0.0/20 . , ISP1 198.32.0.0/20, a ISP2 198.24.0.0/20.

. 3.17 , , , ISP1 ISP2, .. . ISP1, ISP2 (202.24.0.0/20) (198.24.0.0/13 198.32.0.0/13). , Internet . Internet.

3. I

80

. 3.17. ( )

(), IP-, (). , , . , . . IP- , . . . , , , . CIDR Internet. Internet 4 Border Gateway Protocol (BGP-4), . , CIDR . CIDR, Internet , .

IP- . : (Global connectivity); (Private connectivity). 3. I 81

, , Internet. IP-, , . , , IP- .

, , , Internet. , , , , . IP- . IANA IP-, ( " " (private internet)): 10.0.0.0 10.255.255.255 ( ) 172.16.0.0 172.31.255.255 (16 ) 192.168.0.0 192.168.255.255 (256 ) , RFC 19185. , , IANA Internet. , IP-, , - (proxy) (gateway). Internet, , , IP- , Internet, , , . , IP, . IP-. , IP- , IP-. . 3.18 . , . Internet - . , , Internet, , Internet. Internet IP- , IP-.

3. I

82

. 3.18. : Internet, IP- IP-. , Dynamic Host Configuration Protocol (DHCP)6, . DHCP ( IP-) , TCP/IP. DHCP, IP- .

. 3.19. Internet (bastion host), Internet. , (. 3.19) IP-. Telnet , Internet, , Telnet , . , , IP- , "" Internet. (Network Address Translator).

IP- IP- ( ) Network Address Translator (NAT)7. NAT Internet IP- . NAT IP- Internet , , Internet. . 3.20 , IP- 10.1.1.1 10.1.1.2, . 3. I 83

. 3.20. , NAT- IP- ( ) IP- NAT. , IP- 128.213.x.. IP-, IP. , , IP- , . NAT, IP- , . NAT- , , " " . NAT , , IANA . , Internet - . , , . NAT IP- . NAT , , . , , NAT , Cisco Systems Cisco Internetwork Operating System (IOS).

IP 6 IP 6 (IPv6)8 IP (IP next generation IPng) IPv4. IPng 1992 Internet Engineering Task Force (IETF) (). . IPv6 IP, (Quality of Service), 3. I 84

, . IPv6 . , IPv4 IPv6. IPv4 ( ), , IPv6, IP . , IPv6. IPv6 , IPv4. IPv6 128 , 32- IPv4. , Internet. 128 2128 , ! IPv6 , Format Prefix (FP) (. 3.21).

. 3.21. IPv6 . 3.7 . , IPv6 . , , IPv4 . 3.7. IPv6 NSAP IPX

0000 0000 0000 0001 0000 001 0000 010 0000 011 0000 1 0001 001 010 011 100 101 110 1110 1111 0 1111 10 1111 110 1111 1110 1111 1110 10 1111 1110 11 1111 1111

IP IPv4. . 3.22. 3. I 85

. 3.22. IPv6 . (Format prefix) 010, , . (REGISTRY ID) , Internet (PROVIDER ID). (PROVIDER ID) , . (SUBSCRIBER ID) , . (SUBNET ID) , . (INTERFACE ID) , SUBNET ID. , 48- Media Access Control (MAC), IEEE-802.

IPv6 CIDR, IPv4. , .. (. 3.23).

. 3.23. IPv6

IPv4, RFC 1918. : ( 3. I 86

1111111010), . ( 1111111011), .

. 3.24 . ( ) ( ). , Internet, , . , REGISTRY ID, PROVIDER ID SUBSCRIBER ID. IPv6 IPv4, NAT Internet.

. 3.24.

, IP- . IP- , , . . , , . , Internet. , , , . BGP, 5 .

3. I

87

: VLSM om ? VLSM , , , C . VLSM? VLSM IP-. : IP-. B CIDR ? - , , :. , , . ? . , Internet. , , . , RIP-1 IGRP. , CIDR u VLSM? , VLSM CIDR , . , . , , . . , , , , . "" VLSM CIDR, . ? O , . " " . , IP-? , ( ), . , . , o Internet, Internet . IP- , ? , IP- , IP- ( ). Internet, . . ? 3. I 88

& Network Address Translation (NAT), IP-, .

1 2 3 4 5 6 7 8

RFC 791, "Internet Protocol (IP)", www.isi.edu/in-notes/rfc791.txt RFC 917, "Internet Subnets", www.isi.edu/in-notes/rfc917.txt RFC 1878, "Variable Length Subnet Table for IPv4", www.isi.edu/in-notes/rfcl878.txt RFC 1519, "Classless Inter-Domain Routing (CIDR)", www.isi.edu/in-notes/rfcl519.txt RFC 1918, "Address Allocation for Private Internets", www.isi.edu/in-notes/rfcl918.txt RFC 1541, "Dynamic Host Configuration Protocol", www.isi.edu/in-notes/rfcl541.txt RFC 1631, "The IP Network Address Translator", www.isi.edu/in-notes/rfcl631.txt RFC 1884, "IP version 6 Addressing Architecture", www.isi.edu/in-notes/rfcl884.txt

3. I

89

3. I

90

II. ... 4. 5. Border Gateway Protocol 4

: , .. , - , , . , 4 , . , Border Gateway Protocol (BGP). 5 BGP 4 (BGP-4) . , 5 BGP-4, (Capabilities Negotiation) BGP-4 MD5 (TCP MD5 Signature Option) BGP. BGP, II, .

4.

91

: . , (Interior Gateway Protocols IGP). , . . - , . . , (routing policy). , .

4.

92

4. Internet (autonomous systems), . , Interior Gateway Protocols (IGP), : Routing Information Protocol (RIP), Enhanced Interior Gateway Protocol (EIGRP), Open Shortest Path First (OSPF) Intermediate System-to-Intermediate System (IS-IS). Exterior Gateway Protocol (EGP). - Internet 4 (Border Gateway Protocol Version 4 BGP-4), RFC 17711.

, . , . . 1. , (routing protocols). . 2. , . 3. ( ) . 4. (next-hop devices), , , . , , . 5. ( ) (forwarding table). 4. 93

6. , . 7. ( ) , ( ). 8. , ( " " IP TTL IP TOS) . 9. , . (hop-byhop), . , , , , , . . IGP.

. 4.1 RTA, RTB RTC, 192.10.1.0, 192.10.5.0 192.10.6.0 . , . . 192.10.2.0, 192.10.3.0 192.10.4.0. , () . , , RTA RTB 2000, RTA RTC, 60. RTA RTB 56 / , 1 RTA RTC RTC RTB. RTA, RTB RTC IGP . . 4.1 RTA . RIP, OSPF. , , . , 192.10.1.2 192.10.6.2. , , RTA. RTA , , , 192.10.6.0 192.10.3.2 (RTC), 2 (S2). RTC, , ( ). RTC , Ethernet () 192.10.6.2.

4.

94

. 4.1. RIP, OSPF. , RIP - , a OSPF . , . 4.1, RIP OSPF . IGP, .

, , : . , . 4. 95

- - - (Bellman-Ford) 2, 3. (distance vector) , () ( ), , . - , Routing Information Protocol (RIP), . - , ( ) . , , , . ( ), . ( ) , , "", . . , . - , RIP 1 (RIP-1), . , RIP-1, . , . , , RTA (. 4.1). , RIP, OSPF ( ). RIP-1 RTA RTA RTB, 192.10.5.0. RTA , , , RTB, RTC RTB. RTA "" , RTARTB , RTC-RTB . , OSPF , , RTA , RTB RTC (: 60 + 60 = 120; 2 ) , (: 2000; 1 ). , , . . . (, RIP-1) , , 15. . , ( , 15 ). 4. 96

- , (RIP-2 EIGRP) . . - : IP-, . " " (refresh timer), . , " " , , , , . , , - . " ", , . , - , EIGRP RIP-2, (triggerred updates). - , . , , , . , , . , - , , . (convergence) , , .. , . - : , "" () . , , . . . , , " ". - (, RIP) , ( , ) - "" . , . - VLSM CIDR. - , , . RIP-1 , , . IGRP , RIP-1, , , , , . ( , 4. 97

, ) . - , RIP-2 EIGRP, . - . , , RIP-2 EIGRP VLSM CIDR. IGRP EIGRP , , ( , , , (MTU) ..), , . - . , " " . - , EIGRP, . , , BGP - . , , BGP , (path vector), . , ( ), . , , . . , . .

(link-state routing protocols), Open Shortest Path First (OSPF)4 Intermediate Sys-tem-to-Intermediate System (IS-IS)5, . , (link states). . , , , , - . , . - (). ( ), . , . , , , . (link-state database). , 4. 98

. , (shortest path first SPF), , , . . . - , . , . , , RTA, . 4.1. OSPF, RTA , RTB, . 192.10.5.0 (RTB) 192.10.3.2 (RTC). RIP, . . ( ) . , . . . ( ). VLSM CIDR. , . . . , . . , , . , Internet. , , . IGP , , , - : " , 2- : , , " ("Interconnections, Second Edition: Bridges, Routers, Switches and Internetworking Protocols" Radio Perlmanf "OSPF: " . ("OSPF: Anatomy of an Internet Routing Protocol" John T. May)1. (AS), - . OSPF IS-IS. , , IGP IS-IS, OSPF IS-IS. IS-IS, 4. 99

ISP CLNP , . ( , IS-IS CLNP, IP, OSPF IP). Internet, " " IS-IS, OSPF. , . IS-IS, OSPF. IS-IS , .

Internet , (autonomous systems AS), IGP. Internet EGP8 (Exterior Gateway Protocol) ( !). , NSFNET . EGP , , , . - Internet BGP-4.

, AS , AS , AS , .

, Internet, . , , , . . , . , . , , " " . , , , 4. 100

, . . , . . , , . AS, , (.. ). , , , , , . , - . 6, " BGP". , . ( ) . , , . , , , . KISS - , !

(autonomous system AS) , , IGP ( AS ). AS . Internet AS . AS , BGP-4 (. 4.2). , ( iv.ro, Internet OSPF IS-IS ). , AS, , , . AS , , AS. (single-homed), (multi-homed nontranzit) (multihomed tranzit).

4.

101

. 4.2.

AS (stub) , . AS (single-homed) . . 4.3 AS, AS .

. 4.3. AS (AS ) AS Internet . AS , . AS , . . Internet. , . , , . , IP. . IGP. . , . - , IGP. , 4. 102

, BGP . AS AS Internet, .

RFC 19309 , .

AS AS (6541265535), , AS , RFC 227010. . . 4.4 AS . ( EBGP IBGP ). , . , , BGP.

AS (multihomed), . . (nontranzit) AS . , AS. . 4.5 AS (AS1), (ISP1 ISP2). AS , AS . , , AS, . . 4.5 AS1 2 ISP1 5 ISP2. AS1 (nl, 2). ISP2 , ISP1, ISP1 , ISP2. AS1 , , ISP1 5 ISP2 AS1 4. , ISP1 1SP2 AS1 . , AS1 AS .

4.

103

. 4.4. AS : , AS , , . , BGP-4 , .

AS AS AS (. 4.6). ( AS) , AS. BGP-4 , AS . BGP (Internal BGP IBGP), BGP (External BGP EBGP). , IBGP, . , AS.

4.

104

. 4.5. AS AS , AS. , AS , AS. AS BGP-4 AS Internet. , BGP. BGP, , . - BGP . . 4.6 AS1, , ISP1 ISP2. AS1 , 4, 5 ISP1, ISP2, , , ISP1 ISP2. ISP1 AS1 AS , 5 , ISP2 AS 1 , 4.

Border Gateway Protocol Internet. . Interior Gateway Protocols , - BGP. 5, " Border Gateway Protocol 4" BGP-4, . 4. 105

. 4.6. AS BGP

? : . "" , , RIP- OSPF. , AS. Internet RIP. BGP? , BGP. , , , RIP. B IGP. , . IGP BGP? . IGP, BGP. BGP , . , BGP AS. , BGP AS? BGP AS (IBGP) , AS , IBGP . , AS , 4. 106

, IBGP. BGP-4, - BGP-1,2 -3? GP? BGP-4 - , Internet. EGP, BGP-1, 2 3 . CIDR BGP-4, . . Internet. AS peemp cemu lntemet? AS . , AS , . Internet , .

1 RFC 1771, "A Border Gateway Protocol 4 (BGP-4)," www.isi.edu/in-notes/rfcl771.txt 2 Bellman, R. Dynamic Programming (Princeton University Press, 1957) 3 Ford, L. R., Jr. And D. R. Fulkerson. Flows in Networks (Princeton University Press, 1962) 4 RFC 1583, "OSPF version 2," www.isi.edu/in-notes/rfcl583.txt 5 ISO 10589, "Intermediate System to Intermediate System"; RFC 1195, "Use of OSIIS-IS for Routing in TCP/IP and Dual Environments," www.isi.edu/in-notes/rfcll95.txt 6 Perlman, Radia. Interconnections, Second Edition: Bridges, Routers, Switches and Internetworking Protocols (Boston, Mass.: Addison-Wesley Longman, Inc., 1998) 7 Moy, John. OSPF: Anatomy of an Internet Routing Protocol (Boston, Mass.: Addison-Wesley Longman, Inc., 1998) 8 RFC 904, "Exterior Gateway Protocol Formal Specification," www.isi.edu/innotes/rfc904.txt 9 RFC 1930, "Guidelines for creation, selection, and registration of an Autonomous System (AS)," www.isi.edu/in-notes/rfcl930.txt 10 RFC 2270, "Using a dedicated AS for Sites Homed to a Single Provider, "www.isi.edu/innotes/rfc2270.txt

4.

107

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5. Border Gateway Protocol 4

108

5. Border Gateway Protocol 4 Border Gateway Protocol (BGP) BGP-1 1989 . BGP-4 1993 r. BGP, (), (classless interdomain routing CIDR), .AS2 AS1

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OPEN . 5.7 OPEN. 5. Border Gateway Protocol 4 112

. 5.7. OPEN OPEN. (Version) 1 , , BGP-3 BGP-4. , BGP-, . "" , . , , . Cisco Systems , . , , , BGP-4. (My autonomous system) 2 , AS . (Hold timer). " ", 2, , KEEPALIVE UPDATE. , 0 . KEEPALIVE UPDATE 0. , . , , . . 0, , (KEEPALIVE timer) . , 0, , . 0, 3 . , ( , ) ( ) . OPEN. ( ) . BGP (BGP Identifier) , . Cisco (Router ID RID), IP- 5. Border Gateway Protocol 4 113

. IP- , , . (Optional Parameter Length Opt ParmLen). , " ". 0, . (Optional Parameters). , , . () , . ( 1), .

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. 5.8. 5. Border Gateway Protocol 4 114

1.

2.

3.

4.

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5.

6.

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. 5.9. NOTIFICATION NOTIFICATION (1 ), (1 ) . (Error code) , (Error subcode) . 5. Border Gateway Protocol 4 116

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UPDATE BGP . 5. Border Gateway Protocol 4 117

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. 5.11. 5. Border Gateway Protocol 4 118

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. 5.13. best, 1 - internal Origin codes: i - IGP, e - EGP, ? incomplete Network Next Hop Metric LocPrf Weight *> 172.16.1.0/24 172.16.20.2 0 0 3 *> 172.16.2.254/32 172.16.20.2 0 0 3 *> 172.16.20.0/24 172.16.20.2 0 0 3 *> 172.16.65.0/26 172.16.20.2 20 0 3 *> 172.16.220.0/24 172.16.20.2 0 0 3 *> 192.68.5.0 172.16.20.2 20 0 3 *> 192.68.10.0 172.16.20.2 20 0 3 *> 192.68.11.0 0.0.0.0 0 32768

Path ? ? ? ? ? ? ? i

, AS3, OSPF, BGP- AS1. BGP , AS. , AS IP- IP-, . , . , BGP 172.16.2,254/32. 11. BGP 278

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, .

11.22. router ospf 10 passive-interface SerialO network 172.16.0.0 0.0.255.255 area 0 router bgp 3 redistribute ospf 10 match external 1 external neighbor 172.16.20.1 remote-as 1 neighbor 172.16.20.1 route-map BLOCKROUTES out no auto-summary access-list access-list 1 1 permit permit 172.16.2.254 172.16.20.0 deny 10 0.0.0.0 0.0.0.255

2

route-map BLOCKROUTES match ip address 1

route-map BLOCKROUTES permit 20

11.22 , , . 172.16.2.254/32 172.16.20.0/24, BGP. access-list 1 , route-map BLOCKROUTES ( ). (20) BGP. ( , 6, ). 11.23 , BGP- RTC . , 172.16.2.254/32 172.16.20.0/24 . 11.23. BGP- RTC RTC#show ip bgp BGP table version is 34, local router ID is 192.68.11.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal Origin codes: i - IGP, e - EGP, ? incomplete Network Next Hop Metric LocPrf Weight *> 172.16.1.0/24 172.16.20.2 0 0 3 *> 172.16.65.0/26 172.16.20.2 20 0 3 *> 172.16.220.0/24 172.16.20.2 0 0 3 *> 192.68.5.0 172.16.20.2 20 0 3 *> 192.68.10.0 172.16.20.2 20 0 3 *> 192.68.11.0 0.0.0.0 0 32768

Path ? ? ? ? ? i

, 11. BGP 279

network. network , . , ( ). , network 172.16.1.0 mask 255.255.255.0 , 172.16.1.0/24. , ( 255.0.0.0, 255.255.0.0 255.255.255.0), . , , 172.16.0.0/16 network 172.16.0.0. BGP- /. , 192.68.11.0 192.68.11.0/24. , . 11.4, RTA , ( 11.24). 11.24. RTA, , BGProuter ospf 10 passive-interface SerialO network 172.16.0.0 0.0.255.255 area 0 router bgp 3 network 172.16.1.0 mask 255.255.255.0 network 172.16.65.0 mask 255.255.255.192 network 172.16.220.0 mask 255.255.255.0 network 192.68.5.0 network 192.68.10.0 neighbor 172.16.20.1 reniote-as 1 no auto-sum