2 TCP/IP 1 Telnet FTP SMTP SNMP L A N F T P 1-2 FTP FTP FTP TCP IP 1-2 FTP F T P F T P Te l n e t T C P I P 1-2 U N I X F T P T C P I P T C P

Transcription

1 1 1.1 T C P / I P T C P / I P 60 9 ( I n t e r n e t ) WA N 100 T C P / I P T C P / I P [ Lynch 1993] 1.2 Telnet FTP T C P / I P TCP UDP T C P / I P 1-1 1) 1-1 TCP/IP 2) T C P / I P I I C M P I n t e r n e t I G M P I n t e r n e t 3 ) T C P / I P T C P U D P T C P U D P 4 ) T C P / I P IP ICMP IGMP

2 2 TCP/IP 1 Telnet FTP SMTP SNMP L A N F T P 1-2 FTP FTP FTP TCP IP 1-2 FTP F T P F T P Te l n e t T C P I P 1-2 U N I X F T P T C P I P T C P / I T C P / I P T C P I P I n t e r n e t (Internet Protocol Suite) F T P Te l n e t

3 ( i n t e r n e t ) F D D I I P IP Router ( R o u t e r ) g a t e w a y T C P / I P TCP/IP IBM SNA End system Intermediate system En d - t o - e n d Ho p - b y - h o p FTP FTP FTP TCP IP I P 1-3 T C P / I P I P T C P I P T C

4 4 TCP/IP 1 ( m u l t i h o m e d ), T C P / I P F T P Te l n e t L A N TCP /IP [Perlman 1992] TCP/IP T C P / I P TCP/IP

5 1 5 T C P U D P I T C P I P T C P T C 26 Te l n e t R l o g i n 27 F T P 28 S M T P U D P T C P U D P 11 U D P 14 D N S : 15 T F T P 16 BO OT P U D P S N M P U D P 25 I P T C P U D T C P U D P I P 1-4 I P 3 I P 9 10 I P I C M P I P I P 6 I C M P I C M I P P i n g Tr a c e r o u t e 7 8 I C M P I G M P I n t e r n e t U D P 12 U D P 13 I G M P A R P R A R P I P I n t e r n e t I P I P 32 bit I n t e r n e t I P 1-5 A B C D E () 1-5

6 6 TCP/IP 1 32 Dotted decimal notation B IP I P I I P I P Internet Network Information C e n t r e I n t e r N I C I n t e r N I C I n t e r n e t ( I P D N S ) N I C n i c. d d n. m i l I n t e r N I C N I C I n t e r n e t I n t e r N I C r s. i n t e r n i c. n e t I n t e r N I C r s. i n t e r n i c. n e t d s. i n t e r n i c. n e t i s. i n t e r n i c. n e t I n t e r N I C 1. 8 I P I P 3-9 I P I P T C P / I P D N S I P 14 D N S I P I P I P 4 Te l n e t I P 1.6 T C P 1-7 T C P I P T C P T C T C P s e g m e n ti P I (IP datagram) (Fr a m e )

7 I n t e r n e t T C P / I P o c t e t T C P / I P D E C bit 8 byte 1-7 I P p a c k e t I P I P f r a g m e n t IP A p p l TCP TCP IP TCP IP IP TCP 46~ U D P T C P U D I P U D UDP datagram U D P T C P U D P I C M P I G M P I P I I P I 8 b i t 1 I C M P 2 I G M P 6 T C P 17 U D P T C P U D P T C P U D P 16 b i t T C P U D P I P A R P R A R P

8 8 TCP/IP 1 16 bit 1.7 D e m u l t i p l e x i n g 1-8 T C P U D P I P 1-8 I C M P I G M P 1-4 I I P I ICMP IGMP IP A R P R A R P I P 2-4 A R P I T C P I 1.8

9 1 9 I1. I2. I3. I4. I 1 I 2 C1. C2. C3. C 1 T C P U D P U D P T C 1.9 T C P U D P 16 bit T C P / I P F T T C P 21 Te l n e t T C P 23 T F T P ( ) U D P 69 T C P / I P I n t e r n e t Internet Assigned Numbers Authority, IANA U n i x U n i x U n i IANA I n t e r n e t U n i x Te l n e t R l o g i n Te l n e t 23 T C P / I P R l o g i n U n i x Unix T C P / I P

10 10 TCP/IP 1 I n t e r n e t ) Solaris 2.2 T C P U D P E.4 U n i x /e t c / s e r v i c e s Te l n e t TCP 23 UDP 53 TCP U n i x R l o g i n T C P / I P I n t e r n e t 1) Internet I S O C Internet Society I n t e r n e t I n t e r n e t 2) Internet I A B Internet Architecture Board 15 I n t e r n e t I A B I S O C 3) Internet I E T F Internet Engineering Task Force 9 I E T F I n t e r n e t IETF Internet IESG Engineering Steering Group 4) Internet IR I F Internet Research Task Force I RT F I E T F I A B [Crocker 1993] I n t e r n e t 1.11 RFC I n t e r n e t R F C Request for Comment R F C R F RFC 1122 R F C R F C F T P I n t e r n e t R F C

11 1 11 To: Subject: getting rfcs help: ways_to_get_rfcs R F C R F R F C 1 ) R F C Assigned Numbers RFC I n t e r n e t R F C 1340 [Reynolds Postel 1992] I n t e r n e t R F C RFC ) I n t e r n e t RFC 1600[Postel 1994] R F C I n t e r n e t R F C R F C 3 ) R F C [Braden 1989a, 1989b] RFC 1122 RFC 1123 R F C R F C [Borman 1993b] R F C RFC 1127[Braden 1989c] R F C 4) R F C RFC 1009[Braden and Postel 1987] [Almquist 1993] R F C 1.12 Te l n e t 1-9 T C P U D P T C P U D P R F C e c h o d i s c a r d d a y t i m e c h a r g e n T C P U D P t i m e bit U T C

12 12 TCP/IP 1 T C P / I P Te l n e t F T P S M T P N C P N C P A R PA N E T T C P N C P T C P U D P NCP I n t e r n e t I P I n t e r N I C I A N Ai n t e r n e t i n t e r n e t I n t e r n e T C P / I P 100 I n t e r n e t i n t e r n e t i n t e r n e t I n t e r n e t 1.14 T C P / I P TCP 4.x BSD Berkeley Software D i s t r i b u t i o n 1-10 B S D BSD 1.0 (1989) Net/1 T C P / I P B S D AIX 3.2 Net/ BSD TCP/IP I n t e r n e t TCP/IP TCP SLIP BSD 2.0 Te l n e t F T P (1991) Net/2 SunOS 4.x S V R 4 T C P / I P A P Is o c k e t T L I

13 1 13 Transport Layer Interface Berkeley socket AT & T X T I X / O p e n X / O p e n X T I T L I T C P / I P A P I s o c k e t s o c k e t T L I [ S t e v e n s ] ( ) 1-11 IP I P B t u c. n o a o. e d u n o a o National Optical Astronomy Observatories t u c Tu c s o n : s v r 4. t u c. n o a o. e d u I P T C P / I P n o a o. e d u s u n n e t b S L I P 2. 4 S L I P 1.17 TCP/IP

14 14 TCP/IP 1 T C P / I P T C P / I P I T C P U D P I P I n t e r n e t I P I I P 1.1 A B C 1.2 F T P n i c. m e r i t. e d u n s f n e t / s t a t i s t i c s / h i s t o r y. n e t c o u n t N S F N E T R F C [Braden 1989a] T C P / I P 1.4 R F C quote of the day R F C 1.5 T C P / I P I P I n t e r n e t 1.6 RFC 1000 R F C 1.7 I n t e r n e t i s o i s o c. o r g F T P i s. i n t e r n i c. n e t a b o u t - i n t e r n i c / i n f o r m a t i o n - a b o u t - t h e - i n t e r n i c

15 T C P / I P 1 I I P 2 A R P A R P A R P 3 R A R P R A R P R A R P T C P / I P F D D I R S 2 32 S L I P P P P l o o p b a c k S L I P M T U M T U 2.2 IEEE 802 Digital Equipment Corp. I n t e l C o r p. X e r o x 1982 T C P / I P C S M A / C D Carrier Sense, Multiple Access with Collision Detection 10 Mb/s 48 bit I E E E C S M A / C D L L C [Stallings 1987] IEEE 802 T C P / I P I P RFC 894[Hornig 1984] IEEE 802 I P RFC 1042[Postel and Reynolds 1988] R F C I n t e r n e t 10 Mb/s 1) RFC 894 2) RFC 894 RFC 1042 IEEE 802 3) RFC 1042 RFC 894 RFC bit bit 48 bit A R P R A R P bit I P 48 bit 2 80

16 16 TCP/IP 1 38~ ~1492 / 8035 / ~ ~ ~ / 8035 / C R C 8 02 Sub-network Access P r o t o c o l S N A P LLC SNAP Destination Service Access Point, D S A P Source Service Access Point, SSAP 0 x a a Ct r l 3 3 o rg code 0 2 RFC 1340 [Reynolds and Postel 1992] C R C F C S 2-1 IEEE 802.2/802.3 RFC 1042 RFC p a d

17 RFC 893[Leffler and Karels 1984] trailer encapsulation B S D DEC VA X I P I P T C P C R C T C P 512 A R P RFC 893 [ L e ffler et al. 1989] SLIP S L I P Serial Line IP I P RFC 1055[Romkey 1988] S L I P R S I n t e r n e t S L I P 1) IP E N D 0 x c 0 E N D E N D 2) I P E N D 0 x d b 0 x d c 0 x d b S L I P E S C A S C I I E S C 0 x 1 b 3) I P S L I P E S C 0 x d b 0 x d d 2-2 E N D E S C I P I P 4 IP 2-2 SLIP S L I P 1) I P I P 2) S L I P

18 18 TCP/IP 1 3 ) S L I P C R C S L I C R C 3 17 I P T C P 11 U D P S L I P S L I P 1984 Rick Adams 4. 2 B S D S L I P 2.5 SLIP b/s Te l n e t R l o g i n T C P S L I P T C P 1 20 I P 20 T C P R l o g i n C S L I P S L I P RFC 1144[Jacobson 1990a] C S L I P C S L I P 16 T C P S L I P C S L I P SLIP CSLIP 2.6 PPP P P P S L I P P P P 1) I P P P P 8 2) L C P Link Control Protocol 3) N C P Network Control Protocol R F C I P O S I D E C n e t A p p l e Ta l k IP NCP C S L I P N C P T C P RFC 1548[Simpson 1993] RFC 1332[McGregor 1992 ] I P P P P I S O H D L C 2-3 P P P 0 x 7 e 0 x ff 0 x 03

19 IP 2-3 PPP 0 x 0021 I P 0 x c x 802 C R C F C S 0 x 7 e P P P (bit stuff i n g ) [ Ta n e n b a u m 1989 ] 0 x 7 d P P P 6 1) 0 x 7 e 0 x 7 d 0 x 5 e 2) 0 x 7 d 0 x 7 d 0 x 5 d 3 ) 0 x 20 A S C I I 0 x 01 0 x 7 d 0 x S L I P P P P 2 1 P P P S L I 2-2 P P P C R C I P Van Jacobson C S L I P I P T C P P P P S L I P (1) PPP I P (2) (3) I P I P (4) C S L I P T C P I P (5) 3 P P P S L I P S L I P P P PPP PPP SLIP

20 20 TCP/IP Loopback Interface T C P / I P A 127 I P l o c a l h o s t I P I P 2-4 I P IP IP IP I P IP IP IP ARP 2-4 IP 1) I P 2) 12 3 ) I P I P I P 2-4 I P I P B S D

21 2 21 I P B S D u s e l o o p b a c k MTU MTU M T U s (IBM) s (IEEE 802.5) I P M T U I P f r a g m e n t a t i o n M T U I P 2-5 MTU 2-5 M T U RFC 1191[Mogul and Deering 1990] S L I P P P P M T U n e t s t a t M T U 2.9 MTU M T U M T U M T U M T M T U M T U A B B A M T U RFC 1191[Mogul and Deering 1990] M T U M T U I C M P I P I C M P t r a c e r o u t e M T U M T U U D P T C P b/s 8 bit 960 B/s / ms

22 22 TCP/IP 1 S L I P F T ms S L I P Te l n e t R l o g i n F T P 533 ms ms [Jacobson 1990a] S L I P M T U ms C S L I P % 1. 9 % M T U M T U M T U T C P I P 40 M T U I P T C P I P I P I C S L I P S L I P P P P 9600 b/s ms 100~200 ms ms 12.5 ms 2.11 I n t e r n e t I E E E / S L I P P P P S L I P P P P I P I P I P

23 2 23 M T U M T M T U S L I P C S L I P T C P / I P T C P / I 2.1 n e t s t a t( 1 ) 3. 9 M T U

24 3 IP 3.1 I P T C P / I P T C P U D P I C M P I G M P I 1-4 T C P / I P I P X. 25 S N A u n r e l i a b l e I P I I P I C M P T C P c o n n e c t i o n l e s s I P I P A B B A I P I P i f c o n f i g n e t s t a t I P RFC 791[Postel 1981a] I P 3.2 IP I P 3-1 I P ( ) IP 32 IP ( ) 3-1 IP

25 3 IP bit bit bit bit 24~31 bit big endian T C P / I P little endian 4 I P I P v I P 32 bit I P 5 TO S 3 bit 4 bit TO S 1 bit 0 4 bit TO S 4 bit 1 bit 4 0 RFC 1340 [Reynolds and Postel 1992] RFC 1349 [Almquist 1992] R F C TO S 3-2 TO S t c p d u m p 16 UDP TCP IGP 3-2 Te l n e t R l o g i n F T P S N M P Usenet news, NNTP T C P / I P TO S 4.3BSD Reno O S P F I S - I S S L I P

26 26 TCP/IP 1 TO S S L I P T C P T C P TOS I P I P 16 I M T U M T U I P I P 576 T C P T C P U D R I P T F T B O O T P D N S S N M P N F S 8192 I P I P I P I P 46 I P RFC 791 [Postel 1981a] IP I P T C P U D P I P I P 1 IP T T L t i m e - t o - l i v e T T L I C M P 8 Tr a c e r o u t e I P I P I P I C M I G M P U D P T C P I P 0 16 bit 16 bit I P 16 bit

27 3 IP I P I C M P I G M P U D P T C P T C P U D P I P RFC 1071[Braden, Borman and Patridge 1988] I n t e r n e t T T L 1 I P R F C 1141[Mallory and Kullberg 1990] BSD I P I I P bit RFC 1108[Kent 1991] I P 7. 3 I P 7. 4 I P bit 0 I P 32 bit 3.3 IP I P I P 9 I P U n i x 9. 4 I P T C P U D P I C M P I G M P I P I P I P I P I P I P

28 28 TCP/IP 1 1 I P 2 I P next-hop router I P I I P 9. 2 I P h o p - b y - h o p I P I P I P I P 1) I P 2) 3) d e f a u l t I C M P I P 9 I P I n t e r n e t 100 b s d i I P s u n

29 3 IP I P I = ,13,0 s u n 2-1 I P s u n I P bit s u n 48 bit A R P 3-3 bsdi sun b s d i I P f t p. u u. n e t I P b s d i s u n b s d i s u n I P s u n 3-3 I P s u n = ( ) IP = IP= = ( ) IP IP= = ( ) = ( ) IP IP= = b s d i f t p. u u. n e t ( )

30 30 TCP/IP 1 s u n I P s u n s u n n e t b S L I P 2-2 S L I P n e t b s u n n e t b g a t e w a y n e t b A R P bit g a t e w a y I P Tr a c e r o u t e g a t e w a y 1) 2) I P 8. 5 I P I P 3) S L I P A R 9 I C M P I P 3.4 RFC 950 [Mogul and Postel 1985] I P A B I P I n t e r N I C I P B bit 8 bit 8 bit B = B

31 3 IP 31 B 16 bit 8 bit 8 b i t I P A B B C A A I P B I n t e r n e t 3-6 Rn n C 30 B I n t e r n e t B I n t e r n e t I P I P C C 3-6 I n t e r n e t g a t e w a y g a t e w a y 57 k p n o k p n o R 55 R 55 R noao.edu

32 32 TCP/IP I P I P 5 I P I P 32 bit B n o a o. e d u bit B 10 bit 6 bit B B 3-7 B I P I P I I P A B C I P B b i t 8 bit I P B I P 3-8 I P B I P C B B B 3-8 B

33 3 IP 33 I P I P 3.6 IP 7 I P n e t i d s u b n e t i d h o s t i d 0 1 IP 0 0 O K 0 O K 127 O K O K O K n e t i d 1 O K n e t i d n e t i d s u b n e t i d 1 O K n e t i d s u b n e t i d n e t i d 1 1 O K n e t i d 3-9 IP 0 B O O T P I P SLIP s u n S L I P

34 34 TCP/IP A R P 13 S L I P I 8 bit 11 b i t 8 bit 5 bit bit 11 bit RFC 1009[Braden and Postel 1987] RFC[Almquist 1993] 10 R I P R I P 2 O S P F RIP I P bit 13 3 bit S L I P s u n I P s u n bit B = ID ID 8 = x ffffff e 0 5 bit 27 bit 3-10 I P 3-12 IP IP 1 s u n b s d i subnet-directed broadcast address

35 3 IP ifconfig I P T C P / I P i f c o n f i g( 8 ) S L I P i f c o n f i g S L I P A 2. 3 S L I P S L I P L I N K 0 s l i p C S L I P 2. 5 L I N K 1 C S L I P L I N K 2 I C M P 4. 6 S L I P ping 0 b s d i a S u n O S i f c o n f i g w e 0 S I M P L E X 4. 4 B S D B S D / s l i p S L I P b s d i I P slip % /sbin/ifconfig sl0 sl0: flags=1011<up,pointopoint,link0> inet > netmask ffffffe0 s v r 4 S V R i f c o n f i g R U N N I N G svr4 % /usr/sbin/ifconfig emd0 emd0: flags=23<up,broadcast,notrailers> inet netmask ffffffe0 broadcast

36 36 TCP/IP 1 i f c o n f i g T C P / I P 3.9 netstat n e t s t a t( 1 ) - i - n I P M T U 9 n e t s t a t IP 1. 2 I P I n t e r n e t 1) B ) 32 bit I P I n t e r n e t 3) ( f l a t ) C B C I D R Classless Interdomain Routing I P I P 4 21 I n t e r n e t I P I P I P n g IEEE Network (vol.7, no.3) C I D R R F C 1454 [Dixon 1993] 1) SIP I n t e r n e t I P ) PIP 3) TUBA TCP and UDP with Bigger Address OSI C L N P Connectionless Network Protocol I P O S I 20 C L N P S I P P I C L N P RFC 1347[Callon 1992] T U B A [Perlman 1992] 7 I P v 4 C L N P C L N

37 3 IP 37 4) TP/IX RFC 1475 [Ullmann 1993] S I P 64 bit T C P U D P 32 bit 64 bit 64 T C P 32 bit T C P U D P I P v 4 C I D R I P v I P I I P I A B I n t e r n e t i f c o n f i g n e t s t a t I P M T U I n t e r n e t I P bit A 8 B 3.4 RFC 1219 [Tsuchiya 1991] A M T U T C P / I P I [Clark 1988]

38 4 ARP 4.1 T C P / I P I P 48 bit T C P / I P P C 48 bit I P I 32 bit I P 32 Internet RFC 826 [Plummer ] A R P 4-1 A R P 48 R A R P A R P I P 4-1 ARP RARP R A R P X % ftp bsdi 4-2 1) FTP g e t h o s t b y n a m e(3) bsdi 32 bit IP D N S 14 DNS /e t c / h o s t s 2) F T P T C P I P 3) T C P I I 18 4) I P I P I P I P 5) 32 bit I P 48 bit

39 4 ARP 39 I n t e r n e t A R P A R P 6) A R P A R P 4-2 A R P I b s d i I P IP IP IP IP ARP ( ) 4-2 ftp ARP 7) A R P I A R P A R P I P 8) A R P A R P I P 9) I P A R P 48 bit T C P / I P 32 bit I P I P A R P 32 bit I P A R P

40 40 TCP/IP 1 I P 4.3 ARP A R P A R I n t e r n e t 20 a r p(8) ARP a bsdi % arp -a sun ( ) at 8:0:20:3:f6:42 svr4 ( ) at 0:0:c0:c2:9b:26 48 bit a r p 4.4 ARP I P A R P 4-3 A R P I P IP IP 28 ARP / 4-3 ARP 1 A R P 0 x 0806 h a r d w a r e ( ) p r o t o c o l ( ) A R P A R P I P 1 0 x 0800 I P I P I P A R P 6 4 A R P 1A R P 2R A R P 3 R A R P 4 5 R A R P A R A R P I P

41 4 ARP 41 A R P A R P A R P ARP t c p d u m p Te l n e t T C P A R P A t c p d u m p A R P t e l n e t ARP Ctrl Telnet s u n e t c p d u m p 48 bit 4-4 t c p d u m p A A - 3 t c p d u m p 4-4 TCP ARP t c p d u m p 18 1 b s d i 0 : 0 : c 0 : 6 f : 2 d : 40 ff : ff : ff : ff : ff : ff a r p 0 x 0806 A R P a r p i p 60 A R P

42 42 TCP/IP A R P M T U 2-5 M T U I P I P T C P 60 1 arp who-has A R P I s v r 4 I P b s d i t c p d u m p I P 4. 7 n A R P I 2 A R P A R P b s d i 0 : 0 : c 0 : 6 f : 2 d : 4 0A R P t c p d u m p arp reply 3 T C P (s v r 4) 1 8 t c p d u m p 1 A R P A R P 2.2 ms 0.7 ms T C P A R P 3 ms t c p d u m p s v r 4 T C P 4 A R P s v r 4 A R P b s d i A R P A R P I A R P I ARP I n t e r n e t Telnet 76 ARP t c p d u m p 4-5

43 4 ARP ARP e A R P A R P T C P t c p d u m p t e l n e t d a t e Te l n e t 75 B S D T C P T C P A R T C P T C P S Y N T C P A R A R P T C P t c p d u m p T C P ARP A R P 4. 8 a r p 20 3 A R P 20 Host Requirements RFC 4.6 ARP A R P A R P A R P (Proxy ARP) A R P A R P 3-10 s u n 1 s u n A R P s u n Telebit NetBlazer n e t b s u n g e m i n i I P s u n g e m i n i I P A R P n e t b I P g e m i n i I P n e t b n e t b S L I P s u n

44 44 TCP/IP s u n n e t b ARP ARP Telebit NetBlazer s u n ARP ( ) 4-6 ARP g e m i n i a r p s u n n e t b s u n I P A R gemini % arp -a netb ( ) at 0:80:ad:3:6a:80 sun ( ) at 0:80:ad:3:6a: n e t b S L I P I P S L I P I b s d i s l i p I P 3. 8 i f c o n f i g S L I P N e t B l a z e r S L I P I P I P I P I S L I P A R P s u n n e t b n e t b s u n A R P A R P p r o m i s c u o u s A R P ARP (ARP hack) A R P A R P A R P T C P / I P 0 1

45 4 ARP ARP A R P ARP (gratuitous ARP) A R P I P b s d i s u n t c p d u m p ARP n t c p d u m p A R P b s d i : 0 : c 0 : 6 f : 2 d : 40 t c p d u m p 4-4 A R P 1) I P b s d i a : b : c : d : e : f I P 2) A R P A R P [Plummer 1982] I P A R P A R P A R P A R P A R P [ B h i d e E l n o z a h y M o rgan 1991] I P A R P ARP ARP SunOS B S D ARP SVR4 4.8 arp a A R P d A R P

46 46 TCP/IP 1 A R P s I P t e m p p u b - s A R P I P A R P A R P 4.9 T C P / I P A R P A R P a r p a r p A R P A R P A R A R P A R I P A R P A R P bsdi rsh svr4 arp -a A R P ( s v r 4 a r p a 4.2 A R P 4.3 A R P A R P I Host Requirements RFC A R P A R P

47 5 RARP 5.1 I P X I P R A R P R A R I P R A R P A R P R A R P RFC 903 [Finlayson et al. 1984] 5.2 RARP R A R P A R P 4-3 R A R P 0 x 8035 R A R P 3 4 A R P R A R P R A R ( u n i c a s t ) 5.3 RARP s u n b s d i R A R P t c p d u m p 5-1 -e t c p d u m p 5-1 RARP R A R P 1 2 R A R P 2 a t s u n R A R P s u n I P s u n I P T F T R R Q 8 C F C 0 D 21. S U N 4 C T F T P 15 8 s u n I P I P R A R P S U N 4 C t c p d u m p 3 I P 65 U D P U D P t c p d u m p e 5-1

48 48 TCP/IP b s d i t c p d u m p r a r p d 4 2 B S D R A R P t c p d u m p 60 t c p d u m p 60 R A R P I P T F T 16 X R A R P B O O T P T F T P R A R P 5-2 w h o t e l l RARP T C P 5.4 RARP R A R P R A R P A R P T C P / I P I

49 5 RARP 49 I P A R P RARP R A R P I P U n i x / e t c / e t h e r s R A R P T C P / I P R A R P 0 x R A R P A B S D S u n S V R 4 R A R P RARP R A R P R A R P 5-2 R A R P R A R P R A R P R A R P R A R P R A R A R P A R R A R P 5.5 R A R P I R A R P A R R A R P I P R A R P R A R I P 16 B O O T P I P R A R P R A R P T C P / I P R A R P 5.1 RARP A R P R A R P 0 x R A R P

50 6 ICMP Internet 6.1 I C M P I P I C M P I P T C P U D P I C M P IP I C M P I P 6-1 ICMP RFC 792 [Posterl 1981 b ] IP 20 ICMP I C M P ICMP IP 4 15 I C M P I C M P I C M P 3. 2 I P I C M P ( ) 6-2 ICMP I C M P 27 P i n g 9 I P I C M P 6.2 ICMP I C M P 6-3 I C M P I C M I C M P I C M P I C M P I I C M P I P 8 I C M P I

51 6 ICMP Internet P i n g TO S TO S P i n g Traceroute, I P I P 8 T C P U D P T C P U D P 6. 5 I C M P 1) ICMP I C M P I C M 2) 3-9 D 1-5 I P 3) 4) I P ) 6-3 ICMP I C M P

52 52 TCP/IP ICMP I C M P 3. 5 I C M P R A R I B O O T P 16 I C M P 6-4 (17 18) (0) ICMP I C M P i c m p a d d r m a s k I C M P sun % icmpaddrmask received mask = ffffffe0, from received mask = ffffffe0, from b s d i received mask = ffff0000, from s v r 4 s v r 4 s v r S V R 4 B svr4 % ifconfig emd0 emd0: flags=23<up,broadcast,notrailers> inet netmask ffffffe0 broadcast S V R 4 I C M P t c p d u m p b s d i 6-5 e 6-5 ICMP s u n I C M P

53 6 ICMP Internet b s d i s v r 4 I P B S D / 386 R F C E I P sun % icmpaddrmask sun received mask= ff000000, from sun % icmpaddrmask localhost received mask= ff000000, from A I P I C M P 6.4 ICMP I C M P Coordinated Universal Time, UTC U T C I C M P U n i x r d a t e I C M P 6-6 (13 14) (0) ICMP

54 54 TCP/IP i c m p t i m e I C M P I C M P o r i g r e c v x m i t r t t d i f f e r e n c e i c m p t i m e RT T RT T d i f f e r e n c e RT T b s d i s u n 7 ms 8 ms U T C ( ) 4 : 00 U T C b s d i m s B s v r 4 S V R 4 0 S V R 4 I C M P

55 6 ICMP Internet 55 s u n g a t e w a y C i s c o U T C 32 bit U T C s u n N T P stratum 1 N T P d i f f e r e n c e RT T s u n ms ) A S C I I t e l n e t 32 b i t U T C r d a t e T C P Telnet Telnet 2) N T P RFC 1305 [ M i l l s 1992 ] L A N WA N R F C 3) O S F D C E D T S

56 56 TCP/IP 1 [ R o s e n b e rg, Kenney and Fisher 1992] 4) U n i x t i m e d( 8 ) N T P D T S t i m e d 6.5 ICMP I C M P I C M P I C M P I C M P U D 11 U D P U D P U D P I C M P T F T P T F T 15 T F T P U D P 69 T F T P c o n n e c t c o n n e c t g e g e t U D P s v r t c p d u m p TFTP ICMP U D P s v r 4 A R P 1 A R P 2 U D P 3 t c p d u m p A R P I P I C M P 4 T F T P I C M P 5 U D P

57 6 ICMP Internet 57 I C M P 20 U D U D P 20 U D P 20 T F T P 2 9 t e m p. f o o 9 n e t a s c i i T F T P e I C M P IP ICMP ICMP IP ICMP IPUDP UDP ICMP I C M P I C M P 6-3 I P I P 8 I P 8 U D P 11-2 U D P 8888 I C M P I C M 2924 T F T P I P I P I C M P 8 U D P T C P 17-2, T C P 8 I C M P 6-10 (3) (0~15) 0 8 IP ( )+ IP ICMP I C M P I C M I C M P 32 bit 0 4 M T U 2. 9

58 58 TCP/IP 1 MTU 32 bit 16 bit 11.6 I C M P 8 I P 8 Solaris 2.2 i p _ i c m p _ r e t u r n _ d a t a _ b y t e s 64 E. t c p d u m p t c p d u m p TFTP t c p d u m p 6-8 y U D P T C P I C M P T F T P B S D ( s o c k e t ) I C M P U D P c o n n e c t BSD TFTP c o n n e c t I C M P T F T P T C P

59 6 ICMP Internet 59 T F T P R F C Solaris 2.2 AIX I C M P U D 3.5 ms 7 P i n g 6.6 ICMP 4.4BSD I C M P I C M P B S D I C M P D F TO S 12 TO S ( q u e n c h ) T C P U D I P BSD ICMP

60 60 TCP/IP 1 I C M P I C M P I C M P U n i x T C P 6.7 I n t e r n e t 6-3 I C M P I C M P I C M P I C M P I C M I C M P I P 8 I C M P T C P U D P 8 t c p d u m p I C M P U D P 6.2 RFC [Braden 1989a] I C M P 6.3 RFC 1349 [Almquist 1992] I P 3-2 I C M P 6.4 n e t s t a t I C M P

61 7 Ping 7.1 p i n g P i n Mike Muuss I C M P I C M 6-3 I C M P P i n g Te l n e t F T P Te l n e t P i n g P i n P i n g I C M P P i n g I P [Stevens 1990] 11 P i n g P i n g Te l n e t F T P I n t e r n e t I P P i n g Te l n e t Ping p i n g p i n g T C P / I P P i n g 6 I C M P I C M P 7-1 (0 8) ( ) ICMP I C M P

62 62 TCP/IP 1 U n i x p i n g I C M P I D p i n g p i n g 0 1 p i n g I P p i n g s p i n g host is alive 20 no answer LAN p i n g I C M P T T L T T I P B S D p i n g T T L 8 t r a c e r o u t e T T L p i n g I C M P I C M P b s d i 0 ms B S D / ms B S u n t c p d u m p I C M P 4 ms I P s v r 4 I P 14 D N S p i n g 1 I P D N S I P t c p d u m p ms 1 1 A R P

63 7 Ping LAN ping 4 A R P A R P ARP 1 RT T 3 ms A R P A R P s u n p i n g BSD/ ms 10 m s BSD/ p i n g WAN I n t e r n e t

64 64 TCP/IP % I n t e r n e t N + 1 N SLIP S L I P 9600 b / s b s d i s l i p S L I P 1200 b/s P i n g I C M P I P 8 I C M P I 84 t c p d u m p e 2. 4 E N D S L I P 1200 b/s 8 bit 1 bit 1 bit ms m s 2 S V R 4 s I C M P

65 7 Ping 65 8 t r a c e r o u t e S L I P SLIP S L I P s u n n e t b V b/sv. 42 L A P - M V. 42 b i s s u n p i n g g e m i n i 1 RT T 10 ms 10 ms s u n B 1 RT T ms 1 ~ 2 RT T 260 ms 9600 b/s RT T p i n g 60 RT T V. 42 V. 42 b i s 277 ms V. 42 b i s 330 ms V. 42 V. b i s 300 ms RT T 7.3 IP p i n g I P R R p i n g

66 66 TCP/IP 1 R p i n g I P I P R R I P I C M P I P I I C M p i n g I P R R R I C M P R R I C M P I C M P I I C M P I P I 3-1 I P 4 bit I P bit 60 I P 20 R R I P 9 I P A R PA N E T 9 I P 8 Tr a c e r o u t e I P I P R R IP c o d e I P R R 7 l e n R R 39 R R p i n g 39 9 I P I P p t r 1 I P 4 I P I p t r I P p t r 40 I P RFC 791 [Postel 1981a] I P p i n g R R I C M P I P R R p i n g s v r 4 p i n g s l i p ( b s d i ) s v r 4

67 7 Ping I P R R 7-4 ping b s d i I P I I C M P s v r 4 I P v t c p d u m p s u n I P t c p d u m p o p t l e n = 40 I P 40 I P 4 R R { 39 } 39 9 I P # R R p t r I P s u n 7-4 I C M P I P I C M P 3 I P t c p d u m p 7-5 E O L I P end of list E O L 0 39 R R I P R R 0 E O L

68 68 TCP/IP 1 I P 1 N O Pno operation 7-5 S V R 4 T T L 32 B S D / b s d i 1 I C M P T T L 255 T C P / I P B S D / 386 S V R 4 R R I C M P R R I C M P SunOS RR Solaris 2.x I C M P p i n g a i x s u n S L I P s l i p b s d i s l i p R R 9 I P I C M P n e t b a i x I C M P a i x g a t e w a y n e t b I P 7-6 a i x I P n e t b a i x g a t e w a y g a t e w a y g a t e w a y g a t e w a y I C M P a i x 9. 5 I C M P Te l n e t a i x d a y t i m e I C M P

69 7 Ping 69 a i x p i n g n e t b a i x n e t b g a t e w a y 9. 5 I C M P ping ping 7-6 p i n g IP 7.4 IP I P I IP 0 x 44 l e n p t r bit O F F L I P I P 4 0 I P 7-8

70 70 TCP/IP 1 U T C I C M P I P 1 3 I P 8 t r a c e r o u t e 7.5 p i n g T C P / I P I C M T C P / U D PP i n g I C M P L A N WA N S L I P p i n g S L I P p i n g I I P 9 IP p i n g 7.2 b s d i s l i p S L I P 9600 b/s RT T B S D p i n g I C M P 8 0 x c S L I P C S L I P p i n g p i n g p i n g

71 8 Traceroute 8.1 Van Jacobson Tr a c e r o u t e T C P / I P I P Tr a c e r o u t e I P Tr a c e r o u t e I P Steve Deering Van Jacobson C. Philip Wood, Tim Seaver Ken Adelman 8.2 Traceroute 7. 3 I P R R Tr a c e r o u t e I P 7. 3 P i n g I C M P R R I P Tr a c e r o u t e U D P I P I P 9 I A R PA N E T Tr a c e r o u t e I C M P I P T T L T T L 8 bit R F C p i n g I C M P T T L 255 T T L 1 1 T T L 1 RFC 1009 [Braden and Postel 1987] 1 T T L RFC [Almquist 1993] T T L

72 72 TCP/IP 1 T T L T T L I P T T L 0 1 T T L 0 I C M P Tr a c e r o u t e I C M P I P I P Tr a c e r o u t e T T L 1 I P T T L 1 I C M P Tr a c e r o u t e T T L 2 T T L 1 I P I C M P Tr a c e r o u t e U D P U D U D P 6. 5 I C M Tr a c e r o u t e I C M P Tr a c e r o u t e T T L T C P / I P Tr a c e r o u t e 8.3 Tr a c e r o u t e s v r 4 s l i p b s d i b s d i s l i p 9600 b/s S L I P 1 I P t r a c e r o u t e T T L I P 8 U D P T T L T T L I P T T 3 I C M P 5 3 T T L 1 3 I C M P 20 ms 10 ms 10 ms T T L 2 3

73 8 Traceroute 73 I C M P 120 ms T T L 2 t r a c e r o u t e t r a c e r o u t e T T L N + 1 T T L N 8-1 t c p d u m p 1 b s d i 20 ms 10 A R P t c p d u m p 8-1 svr4 slip traceroute tcpdump U D P U D P 12 t r a c e r o u t e 40 t c p d u m p T T L 1 I P [ttl 1] T T L 0 1 t c p d u m p T T L 1 T T L 0 b s d i T T L 0 I C M P I P s l i p I C M P I C M P I C M P c o d e 8-2 I C M P (0 1) ( 0) 8 IP ( ) IP ICMP

74 74 TCP/IP 1 I C M P T T L 0 c o d e 0 I C M P c o d e ~ 14 T T L I C M P S L I P 7. 2 P i n g 1200 b / s U D P U D P 20 I P 2 S L I P 2. 4 P i n g 6-9 I C M P I I P 8 t r a c e r o u t e U D P b/s RT T / ms s v r ms t r a c e r o u t e U D P U n i x t r a c e r o u t e I C M P U D P t r a c e r o u t e I P T T L t r a c e r o u t e I P I C M P t r a c e r o u t e U D P U D P 1 I C M P 3 4 I C M P I U D P I I P 7. 3 I P 2 A B t r a c e r o u t e B A t r a c e r o u t e s l i p s v r 4 t r a c e r o u t e b s d i I P S L I P t r a c e r o u t e I P b s d i 8-3 L A N t r a c e r o u t e I P i f 1 i f 3 I P i f 4 i f 2 i f 2 i f 3

75 8 Traceroute t r a c e r o u t e t r a c e r o u t e I P t r a c e r o u t e I C M P I P I P D N S I P 8.4 t r a c e r o u t e 8-4 s u n NIC (Network Information Center) 8-4 s u n n i c. d n. m i l t r a c e r o u t e D D N N I C n i c. d d n. m i l r s. i n t e r n i c. n e t InterNIC t u c. n o a o. e d u t e l c o m. a r i z o n a. e d u NASA Science Internet n s n. n a s a. g o v T T L 6 7 JPL (Jet Propulsion Laboratory) T T L 11 s u r a. n e t Southeastern Universities Research Association Network T T L 12 G S I Government Systems, Inc., NIC T T L 6 2 RT T 5 90 RT T I P I C M P T T L 3 1 RT T 204 T T L

76 76 TCP/IP 1 RT T 8-5 s u n 8-5 s u n. t u c. n o a o. e d u a w. c o m t r a c e r o u t e t e l c o m. a r i z o n a. e d u w e s t n e t. n e t ( T T L 6 7 ) Advanced Network & Services N S F N E T t 3. a n s. n e tt 3 45 Mb/s a l t e r. n e t a w. c o m 8.5 IP I P Tr a c e r o u t e (source routing) I P I C M P I P Tr a c e r o u t e Tr a c e r o u t e Van Jacobson Tr a c e r o u t e

77 8 Traceroute IP 7-3 I P I P I I P 9 9 c o d e 0 x 83 0 x 89 l e n p t r 7. 3 L S R R S S R R I P p t r 2 (outgoing interface) I P S D R1 R2 R3 8-7 IP # I P I P

78 78 TCP/IP 1 Host Requirements RFC T C P T C T C P T C P t r a c e r o u t e t r a c e r o u t e - g N I C n i c. d d n. m i l NASA Science Internet 8-8 e n s s 142. U T. w e s t n e t. n e t ( ) N S F N E T 8-8 NSFNET n i c. d n. m i l t r a c e r o u t e 16 RT T 350 ms RT T 322 ms 16 N S F N E T I C M P n e t b b u t c h g a t e w a y. t u c. n o a o. e d u G a b b y e n s s 142. U T. w e s t. n e t We s t g a t e. Te l c o m. A r i z o n a. e d u u u - u a. A Z. w e s t n e t. n e t N S F N E T N I C e n s s 142. U T. w e s t n e t. n e t I P I P

79 8 Traceroute 79 I P I D N S T T L 8 RT T n s n - F I X - p e. s u r a. n e t N S F N E T NASA Science Internet t r a c e r o u t e t r a c e r o u t e G g 8-5 N S F N E T n e t b g a t e w a y b u t c h g a b b y. t u c. n o a o. e d u. t e l c o m. a r i z o n a. e d u g a t e w a y g a b b y b u t c h traceroute T T L 3 RT T! S t r a c e r o u t e I C M P 6-3 t y p e 3 c o d e 5 T T L 3 RT T g a t e w a y g a b b y T T L 2 3 g a t e w a y T T L 2 g a t e w a y g a t e w a y T T L 1 T T L I C M P T T L 3 g a t e w a y T T L 2 I C M P 8-10 t c p d u m p s u n n e t b S L I P t c p d u m p v I D S S R R s u n U D P n e t b (w e s t g a t e) 8-7 G g a t e w a y g a b b y (w e s t g a t e) S S R R t r a c e r o u t e 15 16

80 80 TCP/IP t r a c e r o u t e t c p d u m p t r a c e r o u t e A B B A t r a c e r o u t e s u n b r u n o. c s. c o l o r a d o. e d u 8-11 T T L 1 ~ 11 T T L ~ 21 Internet 8-3 T T L g a t e w a y. t u c. n o a o. e d u I P t r a c e r o u t e T T L 2 T T L 19 T T L

81 8 Traceroute t r a c e r o u t e 8.6 T C P / I P t r a c e r o u t e T T L 1 U D P T T L 1 U D P I C M 2 I C M P L A N WA N t r a c e r o u t e I P 8.1 I P T T L t r a c e r o u t e RT T RT p i n g 8.3 t r a c e r o u t e t r a c e r o u t e R 1 R 2 R 3 R 2 T T L 1 T T L 1 I P t r a c e r o u t e 8.4 T T L I C M P T T L

82 82 TCP/IP s u n n e t b S L I P t c p d u m p v I C M P T T L n e t b b u t c h G a b b y e n s s 142. U T. w e s t n e t. n e t T T L S u n O S S V R 4 l p i n g R t c p d u m p 8.7 p i n g t r a c e r o u t e 8.8 p i n g t r a c e r o u t e 8.9 t r a c e r o u t e U D P ~ 5000 t r a c e r o u t e S o l a r i s 2. 2 E RFC 1393 [Malkin 1993b]

83 9 IP 9.1 I P 9-1 I P 9-1 d a e m o n U n i x d a e m o n d a e m o n [Perlman 1992] 10 R I P Routing Information Protocol I P 9-1 I P 30 I C M P 9. 5 r o u t e n e t s t a t route netstat UDP TCP ICMP I P ( ) ( I P ) IP IP IP 9-1 IP

84 84 TCP/IP I P I P 3. 3 I P 1) 2) 3) 0 I P I P s v r 4 r n e t s t a t n I P n n e t s t a t / e t c / n e t w o r k s s l i p b s d i s l i p S L I P b s d b s d i f l a g U G H D 9. 5 M 9. 5 G G I P 3-3 I P 3-4 G I P

85 9 IP 85 G H G H n e t s t a t H 0 I P n e t s t a t R e f c n t Reference count T C P s v r 4 s l i p Te l n e t 1 Te l n e t 2 u s e p i n g 5 i n t e r f a c e l o 0 G H G I P s u n s v r 4 I n t e r n e t s u n S L I P U G s u n IP Host Requirements RFC IP Solaris 2.2 H G I P n e t s t a t x ffffff e ) T C P / I P 2) 3) I n t e r n e t

86 86 TCP/IP 1 4) s l i p b s d i I P s v r 4 1) s u n s l i p l o c a l h o s t e m d 0 2) s l i p I P e m d 0 3) I n t e r n e t a w. c o m e m d 0 4) I P I ftp svr4 ftp ftp localhost ftp I P 2-4 I P I I P I P I P i f c o n f i g H r o u t e s v r 4 route add default sun 1 route add slip bsdi 1 3 d e f a u l t s l i p 4 ( m e t r i c ) r o u t e 0 G 0 G

87 9 IP 87 r o u t e 4. 4 B S D B S D / 386 / e t c / n e t s t a r t S V R 4 / e t c / i n e t / r c. i n e t Solaris 2.x / e t c / r c 2. d / S 69 i n e t SunOS 4.1.x / e t c / r c. l o c a l AIX / e t c / r c. n e t / e t c / d e f a u l t r o u t e r s u n S L I P I n t e r n e t s v r 4 b s d i s l i p 3 ( G H ) S L I P i f c o n f i g sun % ifconfig sl0 sl0: flags=1051<u P, P O I N T O P O I N T, R U N N I N G > inet > netmask ffffff00 ( n e t b), I P ( )(, n e t s t a t I P ) ( G H ) ( S L I P ), S L I P I P ( ) n e t s t a t 3 4 ( s l 0) S L I P I P

88 88 TCP/IP 1 I C M P 9.3 ICMP I P I C M I C M P 6-10 s u n S L I P S L I P s u n B S D 4.4 BSD s u n n e t s t a t S L I P S L I P S L I P S L I P s u n s u n I C M P s v r 4 p i n g S L I P b s d i t c p d u m p p i n g ICMP s u n g e m i n i S L I P I n t e r n e t p i n g I n t e r n e t I P I n t e r n e t IP Internet 8-5 I P 6 N S F N E T 6 N S F N E T I n t e r n e t [Ford, Rekhter, and Braun 1993] top-level routing domain I n t e r n e t I n t e r n e

89 9 IP 89 5 N S F N E T Commercial Internet Exchange: C I XN A S A NASA Science Internet: NSIS p r i n t L i n k I P E B O N E 9.4 I P i p f o r w a r d i n g E B S D / 386 S V R 4 0 SunOS 4.1.x Solaris 2.x B S D 9.5 ICMP I P I C M I P 9-3 I C M P 7-6 1) I P R 1 R 2) R1 R 2 R 2 R 1 L A N 3) R1 I C M P R 2 R 1 (1) IP (3) ICMP (2) IP R1 R2 9-3 ICMP

90 90 TCP/IP R 1 R 2 I C M P T C P / I P R 1 R2 L A N I C M P a i x, s o l a r i s g e m i n i g a t e w a y n e t b g a t e w a y I n t e r n e t S L I P A R P s u n n e t b A R P S L I P n e t b I C M P s o l a r i s p i n g b s d i( ) A R P g a t e w a y p i n g I P 12 p i n g v I C M P p i n g g a t e w a y

91 9 IP 91 I C M P b s d i D I C M P G g a t e w a y (n e t b H b s d i s v r 4 I C M P s l i p b s d i, s v r 4 s l i p s u n I C M P I C M P I C M P 9-4 (5) (0~3) IP 8 IP ( )+ IP ICMP 9-5 I C M P I ( 1 ) I P I C M P I P ( 2 ) I P I P ( 3 ) I P I C M P 4 ~ ICMP I C M P 9-1

92 92 TCP/IP B S D I C M P 1) 2) I C M P 3) 4) i p _ s e n d r e d i r e c t s E B S D SunOS 4.1.x Solaris 2.x AIX SVR B S D I C M P 1) 2) 3) 4) ICMP I C M P RFC 1256 [Deering 1991] I C M P I C M P 9-6 I C M P bit 2 (10) (0) ( 0 ) ICMP

93 9 IP 93 (9) (0) (2) 8 [1] [1] [2] [2] 9-7 ICMP I P I P 32 bit I P 0 x

94 94 TCP/IP 1 I C M P Solaris 2.x i n. r d i s c RFC IP 9.7 I P T C P I P 5 bit I P I I P I P I C M r o u t e I C M P I C M P 9.1 I C M P s v r 4 s l i p B S D 4. 3 B S D B S D 0 ( ) 4. 3 B S D B S D 4. 2 B S D I P A R P a r p I P

95 r o u t e I C M P R I P (Routing Infromation Protocol) T C P / I P O S P F B G P I n t e r n e t B 10.2 routing daemon I P routing mechanism r o u t e routing policy I n t e r n e t I n t e r n e A S Autonomous System N S F N E T I n t e r n e t I G P Interior Gateway Protocol intradomain routing protocol

96 96 TCP/IP 1 I G P R I P I G P O S P F Open Shortest Path First R I P 1986 N S F N E T I G P H E L L O RFC [Almquist 1993] OSPF RIP IGP E G P Exterier Gateway Protocol E G P E G P E G P N S F N E T B G P Border Gateway ProtocolB G P E G 10.3 Unix U n i x r o u t e d T C P / I P R I P g a t e d I G P E G P [Fedor 1998] g a t e d 10-1 r o u t e d g a t e d r o u t e d g a t e d routed gated, 2 gated, r o u t e d g a t e d RIP R I P O S P F B G P 10.4 RIP R I P R I P RFC 1058 [Hedrick 1988a] R F C RIP UDP UDP I P R I IP UDP RIP UDP RIP

97 R I P address family I P 2I R I P 20 R I P R I P = ( 0) (2) ( 0) 32 IP ( 0) ( 0) (1-16) ( ) R I P r o u t e d R I P U D P 520 U D P

98 98 TCP/IP 1 R I P R I P ( h o p ) R I P R2 N3 R 1 N 2 N 2 1 N 1 N 1 N 2 N 1 1 R 2 N 2 1 N R 2 N 1 2 R 1 N 3 A S A S 15 R I P 15 A S 16 I P R I P B 16 bit 0 R I P R I P R I P RFC 1058 [Hedrick 1988a] R I P 15 R I P R1 N1 2 r i p q u e r y g a t e d

99 10 99 r i p q u e r y p o l l 5 R I P c o m m a n d s u n s u n r i p q u e r y n e t b sun % ripquery -n netb 504 bytes from netb ( ): , metric , metric bytes from netb ( ): 244 n e t b 1 n e t b m e t r i c 1 n I P n e t b n e t b t c p d u m p - i s 10 S L I P 1 R I P 1 5 R I P R I P n e t b g a t e w a y r i p q u e r y t c p d u m p - s U D P R I P 10-6 r i p q u e r y t c p d u m p =244 r i p q u e r y n e t b g a t e w a y

100 100 TCP/IP 1 sun % ripquery -n gateway 504 bytes from gateway ( ): , metric , metric g a t e w a y n e t b R I P R I P 10-7 n o a o. e d u R n n I P 10-7 noao.edu s o l a r i s Solaris 2.x s n o o p t c p d u m p Rn P t r udp port U D P R 6 R 4 R 2 R 7 R 8 R 3 6 R R g a t e w a y 15 s n o o p v R I P I U D P R I P R I P 10-9

101 s o l a r i s 60 RIP R s n o o p R I P R I P Address Metric RIP: (not reachable) RIP: RIP: RIP: B n o a o. e d u 10-9 g a t e w a y RIP R 10 R I P s n o o p B R O A D C A S T I P

102 102 TCP/IP RIP 2 RFC 1388 [Malkin 1993a] R I P R I P R I P 0 R I P R I P R I P - 2 R I P - 2 (1-6) (2) (2) 32 IP IP (1-16) ( ) RIP-2 (routing domain) U n i x R I P (routing tag) E G P B G P I P I P I P 0 R I P R I P - 2 R I P 20 0 x ffff 2 16 R I P R I P OSPF O S P F R I P R I RFC 1247 [Moy 1991 ] 2 O S P F 20 R I P O S P F R I P

103 [ P e r l m a n ] 9. 3 O S P F R I P O S P F I P U D P T C P I P p r o t o c o l O S P F 3-1 O S P F R I P 1) OSPF I P 3-2 I P 2) I P 3) O S P F 4) OSPF I P I P ) I P I P 6) R I P ) OSPF 12 O S P F O S P F O S P F R I P 10.7 BGP B G P B G P A R PA N E T E G P RFC1267 [Lougheed and Rekhter 1991] 3 B G P RFC 1268 [Rekhter and Gross 1991] I n t e r n e t B G P B G R F C B G P RFC 1467 [To p o l c i c 1993 ] C I D R B G P B G P A S I P I P I P I n t e r n e t B G P

104 104 TCP/IP 1 1) (stub AS) stub AS 2) (multihomed AS) 3) (transit AS) I n t e r n e t B G P E G P B G P B G P B G B G P R I P O S P F B G P T C P B G T C P B G P B G P R I B G 16 bit B G P k e e p a l i v e T C P 30 k e e p a l i v e T C P k e e p a l i v e CIDR 3 B C B C B C C I D R I n t e r n e t s u p e r n e t t i n g RFC 1518 [Rekher and Li 1993] RFC 1519 [Fuller et al. 1993] [Ford, Rekhter, and Braun 1993 ] C I D R Internet Architecture Board s blessing [Huitema 1993] R F C 1467 [Topolcic 1993] I n t e r n e t C I D R C I D R I P ( s u m m a r i z a t i o n ) 16 C 16 1 I n t e r n e t 8 I n t e r n e t I n t e r n e 8 I P 8 I n t e r n e t 1) I P I P

105 ) 32 bit IP 32 bit 3) 32 bit 32 O S P F R I P B G P 32 bit RFC 1466 [Gerich 1993] C x c x c 3 ffffff C 7 bit I P 0 x c bit 0xfe ( ) C C bit 7 bit C I D R 32 bit (16 C ) I P (0xfffff 000 ) C bit IP I A B C C I D R C I n t e r n e t C I D R I P I [Ford, Rekhter, and Braun 1993] I G P E G P I G P R I O S P F I G P E G P B G P R I P 2 R I P O S P F B G P C I D R C I D R I n t e r n e t O S I I D R P O S I I P B G Intermediate System to Intermediate System I S - I S O S I I G P C L N P I P O S I I S - I S O S P F [Perlman 1992]

106 106 TCP/IP k p n o g a t e w a y 10.2 R I P OSPF R I P 10.4 O S P F 10.5 RFC1058 R I P

107 11 UDP 11.1 U D P U D P I P IP T C P UDP I P UDP UDP U D P I P UDP RFC 768 [Postel 1980] U D P U D P I P U D P T C 17 T C P U D I P M T U 2. 8 I 2. 9 M T U I P 11.2 UDP U D P UDP UDP 8 ( ) 11-2 UDP 1-8 T C P U D P I P I I P T C P U D P I P T C P T C P U D P U D P T C P U D P

108 108 TCP/IP 1 T C P U D P U D P U D U D P 8 0 U D P O K U D P I P 3-1 U D P I P UDP U D P U D P U D P I P I I P U D P T C P U D T C P U D P 3. 2 I P 16 bit U D P 16 bit 0 U D P T C P 12 I P U D P I P I U D PU D P IP 32 IP UDP 0 8 (17) 16 UDP UDP UDP UDP (0) 11-3 UDP U D P

109 11 UDP 109 U D P I P I P U D P U D P U D P 80 U D P U D N F S Network File System U D P U D P S L I P Host Requirements RFC U D P tcpdump U D P U D P t c p d u m p U D P s o c k C 9 U D P 11-4 t c p d u m p UDP U D P IP U D P U D TCP/IP 16 bit D N S D N S U D P UDP [Mogul 1992 ] N F S

110 110 TCP/IP I P I P A R P I 11-5 U D P T C P I C M I P T C P U D P T C P U D C R C U D P T C P 11.4 s o c k t c p d u m p U D P bsdi % sock -v -u -i -n4 svr4 discard connected on to bsdi % sock -v -u -i -n4 -w0 svr4 discard connected on to v e r b o s e - v e p h e m e r a l U D P - u T C P - i - n s v r w 0 0 t c p d u m p UDP t c p d u m p T C P 1 U D P e p h e m e r a l

111 11 UDP IP 2. 8 I P I P M T U I P M T U I P I P T C P U D I P I P 3-1 I P 1 1 I P I C M P 6-3 I P I I P I P I P T C P U D U D P T C P T C P T C P I P [Kent and Mogul 1987] U D P I P T C P T C P s o c k I P 20 U D P , 1472, s o c k bsdi % sock -u -i -nl -w1471 svr4 discard bsdi % sock -u -i -nl -w1472 svr4 discard bsdi % sock -u -i -nl -w1473 svr4 discard bsdi % sock -u -i -nl -w1474 svr4 discard t c p d u m p 11-7

112 112 TCP/IP UDP U D P I P I P t c p d u m p frag frag I P 1480 I P 1480 U D P I P I P I P 3 bit U D P I P U D I P I P I P I I P IP IP 20 UDP 8 UDP (1473 ) IP 20 UDP 8 IP UDP

113 11 UDP ICMP I C M P I D F M T U M T U 2. 9 I C M P bit 16~31 bit M T U 0 (3) (4) ( 0) MTU 8 IP ( )+ IP ICMP I C M P M T U 0 RFC [Almquist 1993] I C M P I C M P n e t b s u n S L I P M T U s u n n e t b M T U S L I P s u n S L I P 3. 9 n e t s t a t M T U 25 S N M P M T U s o l a r i s p i n g b s d i ICMP tcpdump n e t b s u n SLIP MTU s u n t c p d u m p S L I P p i n g

114 114 TCP/IP 1 b s d i t c p d u m p IP s o l a r i s p i n g b s d i t c p d u m p D F I P Solaris M T U 1 n e t b s u n D F n e t b SLIP MTU 2 D F 600 s u n S L I P M T U 5 52 D F s u n I C M P b s d i b s d i s o l a r i s s u n ICMP ICMP ICMP ICMP m t u = 0 s u n I C M P M T U S N M P n e t b S L I P M T U 1500 ICMP DF 11.7 Traceroute MTU M T U t r a c e r o u t e 8 M T U M T U I C M P

115 11 UDP 115 I C M P M T U M T U M T RFC 1191 [Mogul and Deering 1990] M T U M T U s u n s l i p M T U S L I P M T U 2 96 b s d i I C M P M T U M T U T T L 2 1 b s d i I C M P T T L 2 b s d i I C M P M T U M T U 8 M T U M T U t r a c e r o u t e 15 n e t b S L I P M T U M T U 1500 M T U 572 RFC 1191 I C M P 1500 I C M P M T U M T U M T

116 116 TCP/IP UDP MTU U D P M T U M T U Solaris 2.x 650 s l i p s l i p M T U 2 96 S L I P U D P b s d i I C M P M T U tcpdump DF UDP UDP MTU 650 U D P U D P 5 solaris % sock -u -i -n10 -w650 -p5 slip discard t c p d u m p b s d i I C M P M T U ICMP D F 1 1 b s d i 2 D F 1 3 I C M P 4 D F 0 5 I P D F 1 I I P U D P M T U b s d i I C M P M T U I P M T U U D P 8 U D P 20 I P I P U D P 20 I P 7 D F 1 b s d i I C M P I P I P M T U D F I P 30 D F 1 M T U 30 R F C i p _ i r e _ p a t h m t u _ i n t e r v a l E. 4 Solaris 2.2

117 11 UDP 117 U D P U D P M T U i p _ p a t h _ m t u _ d i s c o v e r y M T U U D P UDP MTU s o l a r i s I P M T U 296 s o l a r i s b s d i s l i p t c p d u m p solaris slip s o l a r i s D F 0 M T U b s d i I C M P M T U t c p d u m p D F 1 M T U b s d i 4

118 118 TCP/IP UDP MTU 11.9 UDP ARP U D P U D P A R P s o c k 8192 U D P A R P A R P bsdi % arp -a bsdi % sock -u -i -nl -w8192 svr4 discard A R P A R P I P 5 t c p d u m p A R P A R P t c p d u m p UDP A R P 6 A R P I 6 A R P A R P A R P A R P Host Requirements RFC A R P ARP flooding

119 11 UDP 119 I P A R P 4.3 ms 6 ARP Host Requirements RFC ARP s v r A R P A R P t c p d u m p 5 s v r 4 I C M P I C M 8-2 c o d e 1 I P I C M P B e r k e l e y I C M P U D P 0 A R P 5 1 I C M P I C M P T C P U D P I P U D P A R P U D P I N F S U D P 8192 A R P N F S A R P I P UDP I P I P I P 8 U D P U D P socket API UDP socket U D P 8192 U D P 8192 N F S T C P / I P I s o c k U D P SunOS 4.1.3

120 120 TCP/IP 1 I P B S D / 386 SunOS S u n I P Solaris 2.2 I P Solaris 2.2 AIX IP I P U D U D P D N S 14 T F T P 15 B O O T P 16 S N M P 25 I P U D P B e r k e l e y socket API 4.3BSD Reno S V R 4 socket API( Solaris 2.x) UDP TLI API T C P T C ICMP U D P I C M P (source quench) I C M P b s d i S L I P s u n S L I P b s d i s u n s o l a r i s bsdi % sock -u -i -w1024 -n100 solaris discard t c p d u m p 26

121 11 UDP = 174 (4) (0) ( 0) 8 IP ( ) IP ICMP s u n ICMP b/s s u n n e t b S L I P M T U s u n S L I P RFC 1009 [Braden and Postel 1987] Router Requirements RFC [Almquist 1993] s o c k U D P B S D T C P Unix t i m e s o c k U D P s o c k

122 122 TCP/IP UDP U D P U D P [Stevens 1990] U D P T C P U D P IP U D P I P I U D P U D P U D P I P U D P IP I P Host Requirements R F C T F T P T F T P U D P I P socket API I P _ R E C V D S TADDR socket B S D / B S D AIX S V R 4 SunOS 4.x Solaris 2.x UDP 1. 8 U D P U D P U D P U D P U D P

123 11 UDP 123 U D P U D P b s d i s o c k bsdi % sock -s -u -v -E -R256 -P from , to : s u n from , to : s v r 4 - s - u U D P - v I P - E I P U D P 256 R - r - P 30 U D P s u n sun % sock -u -v connected on to s v r 4 2 svr4 % sock -u -v bsdi 6666 connected on to b s d i 2 s u n 1 s v r t c p d u m p 6 s u n s v r UDP t c p d u m p E I P U D P t c p d u m p I C M P U D P F I F O A R P

124 124 TCP/IP 1 L I F O IP U D P U D P I P ( w i l d c a r d ) U D P 777 U D P sun % sock -u -s 7777 n e t s t a t sun % netstat -a -n -f inet Active Internet connections (including servers) Proto Recv-Q Send-Q Local Address Foreign Address (state) udp 0 0 *.7777 *.* - a - n I P D N S -f inet T C P U D P * I P I P I P I P U D s o c k I P I P I P sun % sock -u -s S L I P ( ) n e t s t a t Proto Recv-Q Send-Q Local Address Foreign Address (state) udp *.* b s d i I C M P UDP I P sockets API S O _ R E U S E A D D R s o c k e t s o c k -A s u n SLIP (IP )

125 11 UDP 125 A 5 n e t s t a t I P I P I P I P I IP n e t s t a t I P *.* I P U D P U D I P U D s o c k - f I P sun % sock -u -s -f I P b s d i n e t s t a t I P Proto Recv-Q Send-Q Local Address Foreign Address (state) udp I P I P I P s u n I P U D P l o c a l I P. l p o r t f o r e i g n I P. f p o r t l o c a l I P. l p o r t *.* l o c a l I P *. l p o r t *.* l p o r t UDP IP l p o r t l o c a l I P I P U D P I P R F C I P

126 126 TCP/IP 1 U D P I U D P I P SunOS I P sun % sock -u -s A sun % sock -u -s 9999 can't bind local address: Address already in use sun % sock -u -s -A A can't bind local address: Address already in use 12 I P U D P A P I - A S O _ R E U S E A D D R s o c k e t 4. 4 B S D s o c k e t S O _ R E U S E P O R T U D P I P I I P I P U D P U D P RFC 768 [Postel 1980] I P U D I C M P M T U 2. 9 Tr a c e r o u t e U D P M T U U D P A R P A R P A R P I P I C M U D P I C M U D P 1473 IEEE RFC 791[Postel 1981a] U D P 11.4 M T U 5 52 S L I P

127 11 UDP 127 I P U D P U D P I P g e m i n i 33 n e t s t a t I P T C P T C P U D P U D P I P I P RFC U D P U D P

128 I P U D P T C P I 48 b i t ( u n i c a s t ) A R P R A R P (multicast) 12-1 t c p d u m p : 00 : 00 : 00 : 00 : 00 ff : ff : ff : ff : ff : ff I P A R P I P I P I P I P T C P U D P U D P I P

129 I C M P T C P U D P U D P U D P 30 U D P U D P 30 U D P I P I P I P B S D r o u t e d r w h o d B S D r w h o U D P Host Requirements RFC A n e t i d n e t i d A I P B

130 130 TCP/IP I P [Almquist 1993] [Almquist 1993] RFC 922 I P B S D T C P / I P 0 IP IEN 212 [Gurwitz and Hinden 1982] 1 I P IENs R F C RFC 894 [Hornig 1984] 4.2BSD RFC 906 [Finlayson 1984] I n t e r n e t R F C RFC B S D 1 90 SunOS 4.x 12.3 T C P / I P sun % ping /usr/etc/ping: unknown host p i n g I P i n e t _ a d d r( 3 ) 32 bit I P D N S 14 p i n g 6 I P

131 I P i f c o n f i g 3. 8 p i n g ARP ARP I P s u n p i n g A R P A R P p i n g A R P A R P 0 x ffffffff s u n A R P t c p d u m p p i n g s u n A R P 4. 5 A R P s u n A R P I A R P p i n g U n i x (raw socket) T F T P T F T 15 bsdi % t f t p tftp> connect tftp> get temp.foo tftp: sendto: Permission denied tftp> q u i t I P A P I U D P

132 132 TCP/IP 1 U D P A P I S O _ B R O A D C A S T UDP E b s d i s l i p p i n g b s d i B S D p i n g D U P! a n g o g h. c x. b e r k e l e y. e d u 14 p i n g s u n I P I C M P n e t b 63 s u n s u n I P I P 12.4 I P 1) T C P T C P 2) 16 B O O T P

133 D I P D 28 ID 12-2 D IP 1-5 I P A B C 28 bit bit (host group) I A N A T C P U D P R F C N T P R I P - 2 ( ) S G I d o g f i g h t I A N A 24 bit 0 0 : 00 : 5 e 00 : 00 : 5 e : 00 : 00 : : 00 : 5 e : ff : ff : ff I A N A 01 I P 01 : 00 : 5 e : 00 : 00 : : 00 : 5 e : 7 f : ff : ff C S M A / C D I n t e r n e t I E E E Assigned Numbers RFC 23 b i t I P 23 b i t 23 b i t bit e e : 00 : 5 e : 00 : 40 : 20 I P 12-1

134 134 TCP/IP 1 5 bit D IP D IP (multicast promiscuous) 48 bit D I P 48 bit I P I P U D P U D P I n t e r n e t I G M P FDDI F D D I D I P 48 bit FDDI [Katz 1990] 12.5

135 D I P 23 bit T C P / I P U n i x 12.4 p i n g sun % ping PING : 1473 data bytes sendto: Message too long? R I P RIP 2

136 13 IGMP Internet I P D I P IP I n t e r n e t I G M P IP IGMP I G M P 20 8 RFC 1112 [Deering 1989] I C M P I G M P I P I G M P I P I G M 13-1 I G M P I I G M P I P IGMP I G M P 13-1 IGMP IP 4 IGMP (1) 4 IGMP (1-2) 8 32 (D IP ) 13-2 IGMP 1 I G M P I G M P 1 2 I C M P D I P 0 I G M P 13.3 IGMP

137 13 IGMP Internet 137 A P I S t a n f o r d U n i x IP socket API Solaris 2.x ip(7) IGMP I G M P 1) I G M P I G M P 2) I G M P I G M P 3) I G M P I G M P I G M P 0 4) I G M P I G M P I G M P I G M P IGMP TTL=1, IGMP = IP = IP = IP IGMP TTL=1, IGMP =0 IP = IP = IP 13-3 IGMP T T L I G M P

138 138 TCP/IP 1 I P 0 ~ I G M P I P I G M P ( T T L ) 1 I P T T L T T L 0 T T L 1 T T L 6. 2 I C M P T T L 0 I C M P T T L Tr a c e r o u t e 8 T T L TTL T T L ( e x p a n d i n g ring search) T T L 1 T T L T T L I G M P I I G M P 13.4 I P s u n

139 13 IGMP Internet 139 n e t s t a t 3. 9 n e t s t a t - n i - n I P - i - a 2 l e : 00 : 5 e : 00 : 00 : S L I P s l 0 l o 0 I P s u n n e t s t a t n e t s t a t s l 0 l o 0

140 140 TCP/IP t c p d u m p t c p d u m p 1 2 I G M P 10 I P s u n I P T T L 1 T T L 0 1 t c p d u m p T T L T T L 1 I P s u n I G M P s u n t c p d u m p T T L D V M R P

141 13 IGMP Internet 141 (Distance Vector Multicast Routing Protocol) D V M R P RFC 1075 [ Wa i t z m a n, Partridge, and Deering] I G M P 2 I P s u n ( I G M P ) [Deering and Cheriton 1990] [Perlman 1992] [Casner and Deering 1992] M B O N E I n t e r n e t I E T F 13.1 I G M P 13.2 [Casner and Deering 1992] U D P M B O N E U D P

142 14 DNS 14.1 D N S T C P / I P I I n t e r n e t I n t e r n e t D N S D N S r e s o l v e r U n i x g e t h o s t b y n a m e(3) g e t h o s t b y a d d r( 3 ) I P I P 4-2 T C P / I P T C P U D P I T C P / I P D N S T C P / I P U D P [Albitz and Liu 1992] U n i x RFC 1034 [Mockapetris 1987a] D N S RFC 1035 [Mockapetris 1987b] DNS D N S B I N D I n t e r n e t n a m e d [ D a n z i g O b r a c z k a Kumar 1992] DNS 14.2 DNS D N S U n i x U n i x. F Q D N Full Qualified Domain N a m e s u n. t u c. n o a o. e d u. D N S

143 14 DNS 143 s u n. t u c. n o a o. e d u DNS 1) a r p a ) 7 3 3) 2 I S O D N S 3 2. u s RFC 1480 [Cooper and Postel 1993]. u s. g o v. m i l. a c. u k. c o. u k D N S 14-1 D N S N I C

144 144 TCP/IP 1 D N S ( z o n e ) n o a o. e d u U n i x D N S U n i x 14-1 Unix D N S I P I P 3 D N S I P I P I P I P F T P f t p. r s. i n t e r n i c. n e t nic.ddn.mil n e t i n f o / r o o t - s e r v e r s. t x t D N S I P DNS D N S 14-3

145 14 DNS ( ) 14-3 DNS bit DNS QR 1 bit 0 1 o p c o d e 4 bit A A 1 bit (authoritative answer) T C 1 bit ( t r u n c a t e d ) U D P R D 1 bit recursion desired 0 R A 1 bit 1

146 146 TCP/IP 1 3 bit 0 r c o d e 4 bit bit 4 ( q u e s t i o n ) DNS DNS ~ ~ bit g e m i n i. t u c. n o a o. e d u 14-6 g e m i n i. t u c. n o a o. e d u ( s u p e r s e t ) IP 14-7 DNS

147 14 DNS 147 A I P P T R I P I P DNS D N S R R Resource Record DNS 14-6 R R 1 I n t e r n e t 2 1 A 4 I P D N S t c p d u m p 14.4 s u n Te l n e t g e m i n i d a y t i m e 3 Telnet daytime Telnet s u n Te l n e t n o a o. e d u

148 148 TCP/IP 1 daytime Te l n e t d a y t i m e T C P I P s u n S L I P Telnet 2 S L I P t c p d u m p 14-9 DNS s u n / e t c / r e s o l v. c o n f sun % cat /etc/resolv.conf nameserver domain tuc.noao.edu 1 n o a o. e d u I P 3. t u c. n o a o. e d u g e m i n i. t u c. n o a o. e d u t c p d u m p I P r e s o l v e r I P I P t c p d u m p I P R D 1 A? A I P g e m i n i. t u c. n o a o. e d u. U D P D N S t c p d u m p 2 1 * A A n o a o. e d u 2 / 0 / 0 3 R R 2 RR R R 0 t c p d u m p A I P

149 14 DNS 149 g e m i n i I P D N S h o s t I P sun % host gemini gemini.tuc.noao.edu A g e m i n i. t u c. n o a o. e d u A h o s t I P B I N D g e m i n i t r a c e r o u t e g e m i n i I P g e m i n i S N M P DNS n s l o o k u p DNS [Albitz and Liu 1992] 10 dig ( I n t e r n e t (Domain Internet Groper) ) D N S doc ( (Domain Obscenity Control) ) d i g F U D P 69 1) 2) g e m i n i. t u c. n o a o. e d u bit 8 bit 14 bit D N S D N S I P U D P D N S U D P I P 12 D N S t e l n e t 2 sun % telnet gemini daytime Trying g e m i n i Connected to gemini.tuc.noao.edu. T e l n e t F Q D N

150 150 TCP/IP 1 IP UDP DNS IP 20 UDP DNS 8 12 ( 14-5) 25 #1(RR) ( 14-8) #2(RR) ( 14-8) DNS (g e m i n i) F Q D N Te l n e t F Q D N Te l n e t g e t h o s t b y n a m e I P F Q D N Te l n e t T C P I P F Q D N Te l n e t I P I P Trying Connected to T C P D N S 14.5 D N S I P 14-1 a r p a i n - a d d r I n t e r n e t D N S n o a o. e d u I P i n - a d d r. a r p a n o a o. e d u B D N S i n - a d d r. a r p a I P 140 I P 252 D N S D N S I P s u n D N S i n - a d d r. a r p a 4 I P A B C I P i n - a d d r F Q D N F Q D N I P D N S a r p a. i n - a d d r e d u. n o a o. t u c. s u n D N S I P i n - a d d r h o s t t c p d u m p D N S i n - a d d r I P g e t h o s t b y a d d r I P i n - a d d r. a r p a

151 14 DNS h o s t t c p d u m p 14-9 s u n h o s t n o a o. e d u s v r 4 I P sun % host Name: svr4.tuc.noao.edu Address: I P h o s t t c p d u m p t c p d u m p P T R D N S 28 4 R R 1 R R P T R 32 bit I P i n - a d d r. a r p a I P U D T C I P U D P T C P I D N S I P F T R l o g i n 26 I P D N S I P I P. r h o s t s I P I P g e t h o s t b y a d d r SunOS 4.13 g e t h o s t b y a d d r / e t c / r e s o l v. c o n f n o a o. e d u s u n S L I P g e t h o s t b y a d d r I P s u n t c p d u m p S L I P I P s u n I P 4

152 152 TCP/IP 1 g e t h o s t b y a d d r R RI P A P T R R R R 20 R R A P T R C N A M E A I P 32 bit I P i n - a d d r. a r p a (canonical name) ( a l i a s ) F T P g a t e d F T P g a t e d. c o r n e l l. e d u g a t e d g a t e d. c o r n e l l. e d u sun % host -t cname gated.cornell.edu gated.cornell.edu CNAM COMET.CIT.CORNELL.EDU H I N F O M X t C P U H I N F O sun % host -t hinfo sun sun.tuc.noao.edu HINFO Sun-4/25 Sun I n t e r n e t I n t e r n e t U U C P 2 M X 3 M X c s. u n i v e r s i t y. e d u 4 M X I n t e r n e t U U C P I n t e r n e t U U N E T M X u s e h o s t f o o. c o m M X

153 14 DNS 153 sun % host -t mx foo.com foo.com MX r e l a y 1. U U. N E T foo.com MX relay2.uu.net M X u s e f o o. c o m r e l a y 1. u u. n e t r e l a y 2. u u. n e t M X 16 bit M X M X T C P M X S L I P N S v T T L I N I n t e r n e t M X 0 S L I P 10 n o a o. e d u R R 14.7 I n t e r n e t D N S U n i x 14-9 s u n n o a o. e d u S L I P s u n t c p d u m p S L I P D N S U D P 53 T C P 53 n a m e s e r v e r d o m a i n sun % cat /etc/resolv.conf domain tuc.noao.edu n a m e r s e r v e r

154 154 TCP/IP 1 h o s t sun % host ftp.uu.net f t p. u u. n e t A host ftp.uu.net t c p d u m p t c p d u m p - w U D P TCP 53 t c p d u m p I P t c p d u m p - r t c p d u m p t c p d u m p ( i d e n t i f i e r ) f t p. u u. n e t I P 8 n s. n i c. d d n. m i l 1 A R A t c p d u m p 10 h o s t

155 14 DNS v A u u. n e t 5 5 I P D N S h o s t n s. u u. n e t f t p. u u. n e t I P 4 h o s t sun % host ftp.uu.net ftp.uu.net A t c p d u m p h o s t h o s t f t p. e e. l b l. g o v sun % host ftp.ee.lbl.gov f t p. e e. l b l. g o v CNAME ee.lbl.gov e e. l b l. g o v A t c p d u m p f t p. e e. l b l. g o v t c p d u m p 1 (c. n y s e r. n e t) f t p. e e. l b l. g o v 4 4 I P 3 n s l. l b l. g o v t c p d u m p C N A M E f t p. e e. l b l. g o v e e. l b l. g o v

156 156 TCP/IP 1 C N A M E L B L F T P f t p f t p. e e. l b l. g o v DNS h o s t C N A M E I P C N A M E A A C N A M E e e. l b l. g o v I P D N S C N A M E A 14.8 UDP TCP D N S U D P T C P 53 D N S U D P T C P t c p d u m p U D P T C T C P U D P T C P 3 T C P D N S U D P U D P I n t e r n e t T F T P B O O T P S N M P D N S D N S 14.9 D N S Rlogin R l o g i n ) I P A 2) 3) A 1 4) R l o g i n I P 5) Rlogin R l o g i n T C P 18 T C P 3

157 14 DNS 157 Rlogin R l o g i n Rlogin 6) Rlogin T C P I P P T R 1 7) i n - a d d r. a r p a 8) P T R 9) P T R F Q D N 10) A I P g e t h o s t b y a d d r R l o g i n i n - a d d r. a r p a 11) A R l o g i n T C P I P A D N S I n t e r n e t D N S I P I P D N S D N S i n - a d d r. a r p a I P 14.1 DNS D N S

158 158 TCP/IP I P I P 14.4 U D P U D P T C P U D P T C P D N S 14-3 RFC I P F T D N S D N S A A?

159 15 TFTP 15.1 T F T P ( Trivial File Transfer Protocol) X 27 T C P F T P T F T P U D P T F T P U D P I P T F T P Bootstrap Protocol T F T P 5-1 s u n T F T P s u n R A R P I P T F T RFC 1350 [Sollins 1992] 2 T F T P 12 [Stevens 1990] T F T P T F T 15.2 T F T P R R Q T F T P 1 2 T F T P W R Q A S C I I n e t a s c i i o c t e t 0 n e t a s c i i A S C I I C R / L F o c t e t 8 bit T F T P ( m o d e ) T F T P 1 T F T P 1 A C K T F T P 2 T F T P 2 A C K T F T P 512 TFTP W R Q TFTP 0 A C K A C K T F T P T C P T F T

160 160 TCP/IP 1 IP UDP TFTP IP UDP (1=RRQ) (2=WRQ) N N ( 3 = d a t a) ( 4 = A C K) TFTP T F T P 5 A S C I I T F T P U D P T F T P ( s o r c e r e r s apprentice s y n d r o m e ) 12.2 [ S t e v e n s 1990] ) U D P T F T P U D P ( 5 = e r r o r) 22 N T F T P b s d i TFTP s v r 4 TFTP U n i x 914 T F T P 962 w c U n i x 48 C R / C F

161 15 TFTP 161 T F T P n e t a s c i i TFTP 1 U D P T F T P 69 t c p d u m p T F T P R R Q 19 U D P n e t a s c i i t c p d u m p 1 T F T P 2 5 T F T P 1 2 T F T P U D 69 R R Q W R Q t c p d u m p s r v T F T P T F T P 10-6 R I P 512 U D P T F T P 69 R R Q W R Q X T F T P 15.4 T F T P 15-1 T F T P T F T P T F T P U n i x

162 162 TCP/IP 1 T F T P U n i x / t f t p b o o t U n i x T F T P I D I D 15.5 T F T P T F T P U D P T C T F T U D P U D P T F T P T F T 2 7 F T P 15.1 Host Requirements RFC TFTP I P 15.2 T F T P RFC T F T P T F T T F T P 15.4 T F T P

163 16 BOOTP I P R A R P I P R A R P 1 I P 2 R A R P R A R P RARP B O O T P B O O T P U D P T F T P 15 RFC 951 [Croft and Gilmore 1985] B O O T P RFC 1542 [Wimer 1993] 16.2 BOOTP BOOTP U D P 16-1 IP UDP 16-1 BOOTP UDP B O O T P Mb/s A R P bit I P I P 0 I P I P I P I P IP UDP BOOTP / U D P

164 164 TCP/IP 1 BOOTP U D P (1=,2= ) (1= ) ( 6) IP IP IP IP 300 (16 ) (64 ) (128 ) (64 ) 16-2 BOOTP B O O T P B O O T P 1 I P I I P I P I P B O O T P BOOTP 67 BOOTP 68 BOOTP 68 B O O T P

165 16 BOOTP B O O T P 16.3 B O O T P X 16-3 t c p d u m p p r o t e u s m e r c u r y t c p d u m p 16-3 BOOTP X t c p d u m p 0 ( 0

166 166 TCP/IP 1 ) 2 I P t c p d u m p p r o t e u s I P m e r c u r y I P m e r c u r y B O O T P A R P I w h o - h a s p r o t e u s I P 4-3 I P A R P A R P 5 I P I P A R B O O T P 1 I P I P 7 2 B O O T P 8 2 m e r c u r y A R P 10 A R P T F T P T F T P = X 16-3 T F T P 15-2 T F T P T F T P t c p d u m p T F T P T F T P T F T P TFTP T F T P T F T P T F T P T F T m e r c u r y T F T P bps F T P T F T X T F T P D N S X X BOOTP B O O T P BOOTP BOOTP 67 U D P RARP 5. 4 R A R P B O O T P B O O T P ( )

167 16 BOOTP 167 TFTP BOOTP U D P I P I P U D P U D BOOTP I P A R P A R P I P R F C 951 Unix i o c t l ( 2 ) A R P a r p - s 4. 8 I P U D B O O T P A R ARP I P B O O T P ARP A R P B O O T P 16.5 BOOTP 5. 4 R A R P RARP B O O T P B O O T P BOOTP Unix BOOTP F relay mode BOOTP B O O T P BOOTP 67 B O O T P B O O T P I B O O T P I B O O T P B O O T P I 1 RFC B O O T P B O O T P B O O T P B O O T P RFC 1533 [Alexander and Droms 1993] 4 I P (magic cookie) 1 0

168 168 TCP/IP tag=1 len= tag=2 len= tag=3 len=n IP IP N 4 14 tag=4~ U T C 4 I P RFC D N S I P 6 I P R F C 16-3 I C M P 6. t c p d u m p B O O T P Host Requirements RFC B O O T P I C M P 64 D H C P Dynamic Host Configuration Protocol B O O T P D H C P 312 RFC 1541 [Droms 1993] 16.7 B O O T P U D P I R A R P

169 16 BOOTP 169 B O O T P I P I B O O T P B O O T P T F T P U D P I P B O O T P R A R P B O O T P U D P B O O T P B O O T P B O O T 16.1 B O O T P R A R P B O O T P R A R P B O O T P R A R P 16.2 B O O T P BOOTP

170 17 TCP 17.1 T C P T C P T C P T C P 7 18 T C P T C P T C P T C P 17.2 TCP T C P U D P I PT C P U D P T C P T C P T C P 18 T C P T C P 12 T C P T C P T C P U D T C P I P s e g m e n t T C P T C P 21 T C P T C P T C P T C P T C P T C P I P I P T C T C P I P T C P T C P T C P T C

171 17 TCP 171 T C P 8 bit T C P byte stream service T C P T C P T C P T C P A S C I I E B C D I C T C P U n i x U n i U n i x 17.3 TCP T C P I P 17-1 IP TCP IP 20 TCP 20 TCP 17-1 TCP IP T C P (6 ) TCP

172 172 TCP/IP 1 T C P I P I P I P T C I P s o c k e t T C P R F C s o c k e t p a i r ( I P I P ) T C P T C P T C P T C P 32 bit S Y N 1 I S N Initial Sequence Number I S N 1 S Y N F I 1 A C K 1 A C K 32 bit A C K T C P A C K 1 T C P T C P T C P T C P A C K T C P 1025 A C K bit 4 bit T C P 60 2 T C P 6 1 U R G A C K P S H R S T S Y N F I N u rgent pointer

173 17 TCP 173 T C P 16 bit T C P T C P T C P T C P U D P U R G 1 T C P MSS (Maximum Segment Size) S Y N M S S T C P T C P 18 T C P 17.4 T C P T C T C P T C P Te l n e t R l o g i n F T P S M T P T C 17.1 I P I C M P I G M P U D P T C P I P 17.2 I n t e r n e t I P, ICMP, IGMP, UDP, TCP 17.3 T C P 17.4 T C P 17.5 T C P U D 11-2

174 18 TCP 18.1 T C P T C P U D P 11 U D P 18.2 T C P s v r 4 Ctrl Telnet t e l n e t ( d i s c a r d ) b s d i T C P t c p d u m p T C P t c p d u m p 18-1 TCP t c p d u m p 7 T C P T C P T C P

175 18 TCP 175 > : T C P t c p d u m p TCP S F. R PT C P ACK U R G t c p d u m p RFC 1025 [Postel 1987], TCP and IP Bake Off K a m i k a z e 1 SYN, URG, PSH, FIN 1 nastygram, (lamp test segment) : ( 0 ) t c p d u m p S Y N F I N R S T ack A C K 1 win T C P <mss 1024> T C P TCP t c p d u m p S Y N S T C P T C K a m i k a z e

176 176 TCP/IP 1 1) S Y N I S N S Y N 1 2) S Y N 2 I S N 1 S Y N S Y N 3) I S N 1 S Y N 3 three-way handshake S Y N active open S Y N S Y N passive open S Y N I S I S N RFC 793 [Postel 1981c] I S N 32 4 m s 1? 4. 4 B S D 1 Host Requirements RFC ms 1 4 ms T C P t e l n e t q u i t

177 18 TCP T C P h a l f - c l o s e T C P F I N F I N F I N F I N T C P F I T C P F I N F I Te l n e t q u i t T C P F I N F I N A C K 1 5 S Y N F I N T C P T C P F I N F I N F I N A C K T C P S Y N F I N q u i t d a y t i m e t c p d u m p E O F t c p d u m p S Y N S 18-1 t c p d u m p 18-5

178 178 TCP/IP t c p d u m p 18.3 t e l n e t 18-6 t c p d u m p 18-6 t c p d u m p S Y N 2 S Y N TCP S Y N t e l n e t : 25 :

179 18 TCP ~ B S D T C P 500 ms 500 T C P t e l n e t 6 12 t i c k 5. 5 ~ ~500 ms ms ms T C P 500 ms ms/ =5.5 TCP 6 (12 ) 500 TCP TCP 500 ms T C P 500 ms [ tos 0x10 ] I P TO S 3-2B S D / 386 Te l n e t 18.4 M S S T C P M S S M S 1024 I P T C P 20 I P M S S M S S S Y N M S S M S S I P 20 T C P 576 I P ) M S S I P T C P T C P S Y N M S S M T U I P T C P M S S 1460 IEEE M S S 1452 B S D / 386 S V R 4 M S S B S D

180 180 TCP/IP 1 M S S 5 12 SunOS Solaris 2.2 AIX M S S [Mogul 1993] 1460 M S S 1024 M S S I P ( n o n l o c a l )M S S 536 I P I P I T C P E E - 1 M S S M T U M S S M T U s l i p M T U 2 96 S L I P b s d i 18-8 s u n 18-8 s u n s l i p TCP MSS s u n s l i p T C P t c p d u m p t c p d u m p s u n s l i p s u n 256 M S S s l i p M T U 296 s u n M S S M S S 576 M T U 536 M S S 296 M T U M T U TCP T C P

181 18 TCP 181 F I N F I N c l o s e s h u t d o w n 2 1 A P I close read A C K 19 F I N TCP U n i x r s h( 1 ) sun % rsh bsdi sort < datafile b s d i s o r t r s h d a t a f i l e r s h T C P r s h d a t a f i l e T C P T C P T C P F I Nshutdown EOF F I N A C K write close EOF F I N sun TCP bsdi rsh bsdi sort < datafile b s d i r s h d s o r t T C P 14 [Stevens 1990] U n i x T C P T C P s o r t T C P r s h s o r t d a t a f i l e r s h

182 182 TCP/IP 1 T C P s o r t T C P T C P r s h T C P T C P 18.6 TCP T C P SYN SYN SYN,ACF : : : FIN FIN ACK : FIN FIN : ACK : ACK ACK : ACK : FIN : ACK 2MSL TCP TCP TCP

183 18 TCP 183 E S TA B L I S H - E D E S TA B L I S H E D E S TA B L I S H E D 4 C L O S E _ WA I T L A S T _ A C K 1 1 CLOSED, LISTEN, SYN_SENT n e t s t a t n e t s t a t RFC 793 C L O S E D TCP L I S T E N S Y N _ S E N T T C P S Y N _ R C V D L I S T E N S Y N _ S E N T S Y N _ R C V D L I S T E N L I S T E N S Y N A C K S Y N S Y N _ R C V D R S T A C K L I S T E N T C P MSL T I M E _ WA I T 2 M S L T C P M S L Maximum Segment Lifetime T C P I P I T T L RFC 793 [Postel 1981c] MSL ) 8 I P T T L M S L T C P

184 184 TCP/IP 1 A C K T I M E _ WA I T 2 M S L T C P A C K A C K F I N 2 M S L T C P 2 M S L I P I P 2 M S L T C P 2 M S L A P I A P S O _ R E U S E A D D R 2 M S L TCP 2MSL 2 M S L 2 M S (socket pair) i n c a r n a t i o n i n s t a n c e T I M E _ WA I T T I M E _ WA I T 2 M S L 1 ~ 4 s o c k 6666 ( bsdi ) 2 M S L n e t s t a t 2 M S L 2 M S L SunOS S V R 4 B S D / 386 AIX M S L 30 Solaris 2.2 4

185 18 TCP 185 MSL 2 2 M S L 1 - v b M S L 2 M S L 27 F T P I P I P 4 2 M S L 2 M S L S O _ R E U S E A D D R T C P 6666 ( bsdi ) 6666 A 1 s o c k 6666 b s d i I P I P M S L 2 s o c k 6666 b s d i M S L 4 A S O _ R E U S E A D D R s o c k b s d i M S L s u n A M S L sun % sock -A -s M S L b s d i bsdi % sock -b1098 sun 6666

186 186 TCP/IP 1 connected on to T C P T I M E _ WA I T I S N RFC 1185 [Jacobsan B r a d e n Zhang 1990] 27-8 F T P 2 M S L M S L 2 M S L 2 M S L M S 2 M S L RFC 793 T C P M S L (quiet time) MSL FIN_WAIT_2 F I N _ WA I T _ 2 F I N F I N F I N _ WA I T _ 2 T I M E _ WA I T C L O S E _ WA I T F I N _ WA I T _ T C P C L O S E D 18.7 T C P R S T referenced connection T C P I P I P RFC 793

187 18 TCP U D P 6. 5 I C M P T C Te l n e t bsdi % telnet svr Trying telnet: Unable to connect to remote host: Connection refused Te l n e t bsdi.1087 > svr : S : (0) win 4096 <mss 1024> [tos 0x10] (0.0038) svr > bsdi.1087: R 0:0(0) ack win A C K 1 0 I S N S Y N 1 I S N 0S Y N F I N orderly release F I N F I N abortive release 1 2 R S T A P I s o c k Socket API linger on close S O _ L I N G E R - L 0 F I N s o c k bsdi % sock -L0 svr hello, world ^ D t c p d u m p 1 ~ U n i x

188 188 TCP/IP RST FIN 6 C o n t r o l _ D - L 0 b s d i T C P R S T F I N R S T R S R S T svr4 % sock -s 8888 hello, world read error: Connection reset by peer 8888 T C P R S T T C P H a l f - O p e n P C Te l n e t P C P C P C Te l n e t T C P 23 T C P k e e p a l i v e T C P b s d i Te l n e t s v r 4 t c p d u m p F I N T C P T C P T C P

189 18 TCP t c p d u m p M S S ~ 3 4 h i t h e r e 5 s v r 4 s v r another line A R P A R R S T Te l n e t 18.8 S Y N S Y N simultaneous open A 7777 B 8888 B 8888 A 7777 A Te l n e t B Te l n e t B Te l n e t A Te l n e t Te l n e t Te l n e t Te l n e Te l n e t T C P O S I S Y N S Y N _ S E N T S Y N S Y N _ R C V D 18-12

190 190 TCP/IP 1 S Y N S Y N S Y A C K E S TA B L I S H E D ( ) ( ) S Y N b s d i v a n g o g h. c s. b e r k e l e y. e d u S L I P S Y N b s d i b 7777 FIN v s o c k I P M S S EOF v a n g o g h S Y N T C P v a n g o g h 4. 4 B S D S Y N 1 ~ 2 A C K S Y N 3 ~ 4 5 b s d i v a n g o g h hello, world 6 7 ~ 8 and hi there 9 ~ 12 T C P

191 18 TCP 191 S Y N S Y N A C K S Y N _ S E N T SYN_RCVD TCP F I N T C P simultaneous close E S TA B L I S H E D F I N _ WA I T _ 1 F I N F I N F I F I N _ WA I T _ 1 C L O S I N G A C K A C K T I M E _ WA I T ( ) ( ) TCP T C P 17-2 T C P S Y N M S S R F C RFC 1323 [Jacobson, Braden Borman 1992] T C P

192 192 TCP/IP 1 T C P T C P RFC 793 RFC TCP 1 k i n d k i n k i n d l e n k i n d l e B S D T C P t c p d u m p S Y N T C P <mss 512, nop, wscale 0, nop, nop, timestamp > M S S 512 N O P N O 4 10 N O P k i n d A C K A C K RFC T C P T / T C P kind 11, TCP T C P U n i x f o r k t h r e a d T C P

193 18 TCP TCP T C P T C P n e t s t a t Te l n e t Te l n e t Te l n e sun % netstat -a -n -f inet Active Internet connections (including servers) Proto Recv-Q Send-Q Local Address Foreign Address (state) tcp 0 0 *.23 *.* LISTEN - a E S TA B L I S H E D - n I P D N S 23 Te l n e t-f inet T C P U D P *. 23 S Y N I P I P 2 3 Te l n e t *.* I P L I S T E N s l i p Te l n e t Te l n e n e t s t a t Proto Recv-Q Send-Q Local Address Foreign Address (state) tcp ESTABLISHED tcp 0 0 *.23 *.* LISTEN 23 1 E S TABLISHED I P I P I P L I S T E N Te l n e t T C P E S TA B L I S H E D E S TA B L I S H E D 23 L I S T E N s l i p Te l n e t Te l n e t n e t s t a t Proto Recv-Q Send-Q Local Address Foreign Address (state) tcp ESTABLISHED tcp ESTABLISHED tcp 0 0 *.23 *.* LISTEN E S TA B L I S H E D 2 3 Te l n e t

194 194 TCP/IP 1 s l i p T C P 4 I P I P T C 23 L I S T E N E S TA B L I S H E D S Y N L I S T E s o l a r i s 3 Te l n e t S L I P s u n Proto Recv-Q Send-Q Local Address Foreign Address (state) tcp ESTABLISHED tcp ESTABLISHED tcp ESTABLISHED tcp 0 0 *.23 *.* LISTEN E S TA B L I S H E D I P s u n S L I P IP I P I P s o c k I P I P L I S T E N I P sun % sock -s S L I P n e t s t a t Proto Recv-Q Send-Q Local Address Foreign Address (state) tcp *.* LISTEN s o l a r i s S L I P Proto Recv-Q Send-Q Local Address Foreign Address (state) tcp ESTABLISHED tcp *.* LISTEN T C P t c p d u m p S Y N R S T IP I P T C P

195 18 TCP IP U D P I P I P RFC 793 A P I I P T C P l p o r t l o c a l I P I P T C 1 I P ( ) Local IP Lport TCP IP T C P T C P 1) T C P T C P 2) ( b a c k l o g ) 0 ~ ) S Y N T C P BSD S o l a r i s T C P T C P S o l a r i s B S D

196 196 TCP/IP ) T C P T C P S Y N T C P ) 5) T C P S Y N R S T T C P s o c k - O t c p d u m p bsdi % sock -s -v -q1 -O q 1 1 B S D O s u n t c p d u m p 1 1 S Y N M S S T C P 1090 T C P 1 ~ T C P 4 ~ 6 T C P t c p d u m p

197 18 TCP T C P S Y N 9, 10, 11, 12, 15 S Y N 4 3 S Y N ( S Y N 15 ~ T C P T C P SunOS 4.13 T C P S Y N R S T T C P S Y N T C P S Y N T C P / I P T C P S Y N I P T C P A P I T L I T C P O S I T C P Solaris 2.2 T C P t c p _ e a g e r _ l i s t e n e r s E. 4 T C P T C P I P F I N R S T T C P 4 t c p d u m p T C P

198 198 TCP/IP 1 T C P T C P T C P T C P T C P 4 I P I T I M E _ WA I T T C P M S L I S N I S N I S N 521? T C P T C P s o c k 2 M S L M S L s o c k d a y t i m e 2 M S L F I N _ WA I T _ 2 11 C L O S E D C L O S E _ WA I T F I N 12 T C P F I N A R P A R P s v r 4 b s d i A R P A R P 18.9 t c p d u m p 18-13

199 18 TCP F I N A C K F I N R S T ? TCP M T U D N S T C P U D P M S L RFC 793 T I M E _ WA I T F I N RFC 793 T I M E _ WA I T R S T Host Requirements RFC T C P T C P

200 19 TCP 19.1 T C P T C T C P [Caceres et al. 1991] T C P F T U s e n e t Te l n e t R l o g i n 90 % 1 0 % f u l l - s i z e d 512 Te l n e t R l o g i n 90 % 10 T C P R l o g i n N a g l e Te l n e t 19.2 R l o g i n T C P / I P R l o g i n R l o g i n 26 Te l n e t d a t e \ n B S D / 386 R l o g i n TO S

201 19 TCP d a 4 ~ 6 t 7 ~ ~ 12 e 3 ~ 4 6 ~ 7 9 ~ ~ ~ 15 R E T U R N U N I X C R / L F 1 6 d a t e C R / L F 7 18 svr4 % Rlogin date T C P b s d i s r v 4 7 A C K A C T C P A C K A C K A C K 200 ms T C P 200 ms b s d i A C K

202 202 TCP/IP ms A C K ms ms T C P ms 16.4, 474.3, 831.1T C P 200 ms 1~200 ms ( ) 19-3 rlogin date s v r ms 200 ms A C K 16 ms 200 ms A C K ms T C P

203 19 TCP ms 500 ms T C P 1~200 ms 1~500 ms Host Requirements RFC T C P A C K 500 ms 19.4 Nagle, R l o g i n I P 20 T C P 1 t i n y g r a m RFC 896 [Nagle 1984] N a g l e T C P T C P m s 60 RT T s l i p v a n g o g h. c s. b e r k e l e y. e d u R l o g i n S L I P I n t e r n e t s l i p v a n g o g h A C K N a g l e N a g l e N a g l e 19-4 A C K A C K 12 A C K 3 18, ACK T C P 3

204 204 TCP/IP 1 R l o g i n T C P T C P T C P s l i p v a n g o g h. c s. b e r k e l e y. e d u r l o g i n Nagle N a g l e X A S C I I ( e s c a p e ) T C P A S C I I E S C 200 ms API T C P _ N O D E L A Y Nagle Host Requirements RFC T C P N a g l e

205 19 TCP N a g l e s l i p v a n g o g h. c s. b e r k e l e y. e d u R l o g i n F 1 3 e s c a p e M F t c p d u m p F1 F Nagle F1 F2 F2 F1 F1 F Nagle

206 206 TCP/IP 1 r l o g i n 1 T C P 1 F A S C I I 2 M 6 ~ s l i p 200 ms A C K N a g l e r l o g i n 19-7 t c p d u m p F1 F Rlogin Nagle t c p d u m p N a g l e t c p d u m p A C K T C P

207 19 TCP 207 N a g l e N a g l e 21 F1 F2 F2 F1 F1 F Nagle s l i p 4096 v a n g o g h 8192

208 208 TCP/IP T C P R l o g i n T C P A C K T C P A C K T C P R l o g i n R l o g i n Te l n e t R l o g i n N a g l e N a g l e 19.1 T C P s u n t c p d u m p b s d i b s d s l i p s l i p ms s u n s l i p 9600 b/s C S L I P N a g l e 19-6 N a g l e 19-8

209 20 TCP T F T P T C P T C P P U S H T C P 20.2 s v r b s d i b s d i s o c k bsdi % sock -i -s i - s s i n k 7777 svr4 % sock -i -n8 bsdi M S S 3 4 ~ A C K I P I P I P T C T C P 4 T C P 5 T C P 2048 A C K 7 T C P A C K T C P ~ I P A C K

210 210 TCP/IP s v r b s d i A C K T C P T C P A C K t c p d u m p T C P T C P T C P T C P A C K 4097 A C K 4 A C K

211 20 TCP A C K 17 F I N A C K s v r 4 b s d i S p a r c b a c k - t o - b a c k A C K A C K 8 0 T C P A C K 17.4 ms 4096 A C K 4 10 ~ 13 1 P U S H F I N A C K F I N 8192

212 212 TCP/IP ASAP 20-4 TCP 1 11 o ff e r e d w i n d o w

213 20 TCP 213 1) 2) T C P 3) Host Requirements RFC T C P A C K A C ,5, ,12, ) 2)

214 214 TCP/IP 1 3) 7 8 4) A C K A C K 20.4 T C P 4. 2 B S D B S D SunOS B S D / 386 S V R Solaris B S D AIX A P I [Mogul 1993] % [ P a p a d o p o u l o s Parulkar 1993] s o c k bsdi % sock -i -s -R R s u n 8192 sun % sock -i -n1 -w8192 bsdi ~ F I N F I N

215 20 TCP PUSH T C P P U S H P U S H T C P T C P T C P U S H P U S H P U S H T C P P U S H T C P T C P P U S H A P I T C P P U S H P U S H T C P P U S H P U S H

216 216 TCP/IP 1 P U S H TCP A P I T C P P U S H PUSH P U S H ~ ~ P U S H P U S H 1 7 P U S H A C K 0 0 A C K A C K ( ) F I N T C P 2048 M S S % P U S H ~ 7 T C P I T C 4096 T C P T C P 4 13 P U S H 20.6 [Jacobson 1988] T C P T C P (slow start) T C P (congestion window) c w n d

217 20 TCP 217 T C P 1 A C K c w n d A C K A C K 1 2 A C K 4 T C P s u n v a n g o g h. c s. b e r k e l e y. e d u S L I P T C P A C K A C K 716 ms 2 5 A C K 3 A C K

218 218 TCP/IP T C P T C P 1 6 1, 2, 3, A C K A C K ~ , A C K 8 RT T R o u n d - Trip Ti m e A C K I P T C P A C K

219 20 TCP A C K A C K A C K T C P ( s e l f - c l o c k i n g ) A C K A C K ACK A C K ~ 19 1 A C K 23 4 A C K ~ ~31

220 220 TCP/IP 1 31 ( p i p e ) A C K c a p a c i t y (bit) = b a n d w i d t h (b/s) ro u n d-trip time ( s ) RT T RT T 60 ms T b/s T b/s T C P T C P T C P T b/s 193 bit b/s T b/s b/s Mb/s 45 Mb/s RT T RT T RTT RTT 20-12

221 20 TCP ~ 20 A C K R 1 R2 R 3 R R 1 R 1 R 3 R 2 R 4 R ~ 20 2 A C K T C P ( u rgent mode) T C P 17-2 U R G 1 16 b i t T C P T C P Host Requirements RFC

222 222 TCP/IP 1 Host Requirements RFC T C P T C P T C T C P U R G T C P (out-of-band data) T C P T C P T C P A P I TCP Te l n e t R l o g i n 26 F T P 27 Te l n e t R l o g i n T C P 0 T C P U R G T C P Te l n e t 255 T C P b s d i s o c k 10 - P bsdi % sock -i -s -P s u n S n - U 5 5 1

223 20 TCP t c p d u m p 1 ~ A C K U R G 5 A C K 13 ms 6 ~ 10 1 A C K T C P 2048 T C P T C P 4 A C K T C P T C P T C P A C K 4 A C K T C P A C K 4 5 A C K T C P t c p d u m p TCP

224 224 TCP/IP SunOS TCP T C P T C P T C P T C P T C T C P T C P P U S H T C P T C P

225 20 TCP b s d i P U S H 20.3 U s e n e t 128 ms b/s b/s 47 % b/s ms 20.4 A P I T C P P U S H P U S H A C K A C K

226 21 TCP 21.1 T C P T C P I C M P T F T P U D P A R P 4. 5 T C P S Y N T C P 4 1) 2) ( p e r s i s t ) 2 2 3) ( k e e p a l i v e ) 23 4) 2MSL T I M E _ WA I T T C P T C P T C T C P T C P T C P T C P T C P 21.2 T C P T C P 9 TCP

227 21 TCP t c p d u m p b s d i 21-1 TCP T C P 4 hello, world1 2 5 s v r 4 6 and hi 7 ~ T C P (exponential backoff ) 6. 5 T F T P T C P Solaris 2.2 E. 4 t c p _ i p _ a b o r t _ i n t e r v a l T C P RT T T C P T C P RT T A C K

228 228 TCP/IP RT T 4 1 ~ ~ 1024 A C K M RT T T C P T C P RT T O R R+ ( 1 )M 0. 9 RT T % RT T RFC 793 RTO Retransmission Ti m e O u t RTO = R 2 [Jacobson 1988] RT T J a c o b s o n RT T RT T RTO [Jacobson 1988] 5 6 RFC 793 RTO RTO J a c o b s o n RT T M E rr = M A A A + g E rr D D + h( E rr D) RTO = A + 4D A RT T D E rr RT T A D RTO g 1 / h RT T RTO [Jacobson 1988] RTO 2 D [Jacobson1990c] 4D BSD Net/1 J a c o b s o n g, h 4 2 J a c o b s o n 1 g J a c o b s o n RTO T RT T Karn RTO

229 21 TCP RTO A C K [Karn and Partridge 1987] RT T A C K A C K RTO RTO RTO 21.4 RTT T C P s o c k s l i p v a n g o g h. c s. b e r k e l e y. e d u slip % sock -D -i -n32 vangogh.cs.berkeley.edu discard s l i p S L I P I n t e r n e t 9600 b/s S L I P s l i p b s d i M T U s l i p t c p d u m p - D A. 6 t r p t( 8 ) RT T t c p d u m p t c p d u m p A C K s l i p 4096 v a n g o g h 8192 s l i p 1 ~ t c p d u m p RTT 21-2 RT T T C P RT T

230 230 TCP/IP RTT 500 ms T C P 550 ms RT T ms 2 ( 1000 ms) A C K RT T RT T t c p d u m p 3 T C P RT T 1500 ms ms 4 5 t c p d u m p RT T RT T ms RT T 2 7 9

231 21 TCP t c p d u m p RT T RTT 500 ms t c p d u m p ~ RT T RT T 21-4 RT T t c p d u m p T C P RTO 21-2 x S Y N TCP RTO ( ) RTT 21-4 RTT TCP RTO RT T RT T 10, K a r n T C P RTO 500 ms RTT ( ) RT T RT T A D 0 3

232 232 TCP/IP 1 RTO = A + 2D = = 6 s 2D 4D A RTO S Y N RTO S Y N 21-5 t c p d u m p SYN RTO RTO = A + 4D = = 12 s RTO RTO S Y N A C K 467 m s A D K a r n 4 A C K A C K RTO K a r n 24 RT T RTO 24 1 A C K A = M = = 2 D = A/2 = 1 3 M 1. 5 A D 0 RTO 3 1 RT T M RTO RTO = A + 4D = = 6 s 2 A C K E rr = M A = = 1. 5 A = A + g E rr = = D = D + h( E rr D) = ( ) = RTO = A + 4D = = E rr A D RTO

233 21 TCP S Y N S Y N 6. 3 F I N F I N A C K ( ) 21-6 s l i p v a n g o g h t c p d u m p 21-7 ( ) 72 s l i p 4096 v a n g o g h s l i p t c p d u m p s l i p

234 234 TCP/IP 1 44, v a n g o g h A C K 256 (HOLE) ( 256 ) ( 256 ) ( 256 ) ( 256 ) ( 256 ) ( 256 ) ( 256 ) ( 256 ) s l i p A C K 62 3 A C K T C P A C K 3 J a c o b s o n T C P 43 T C P

235 21 TCP T C P A C K v a n g o g h 7 48, 50, 52, 54, 55, T C P A C K T C P v a n g o g h 6657 A C K 63 T C P 6657 ~ A C K t c p d u m p A C K [Jacobson 1988] 1 % RT T c w n d s s t h re s h 1) c w n d 1 s s t h re s h ) TCP c w n d 3) s s t h re s h c w n d 2 c w n d 1 4) c w n d c w n d s s t h re s h 2 c w n d

236 236 TCP/IP c w n d 1 /c w n d (additive increase) c w n d 1 RT T A C K c w n d 4. 3 B S D 4. 4 B S D 1 8 [Floyd 1994] [Leffler et al. 1989] 4.3BSD Tahoe 4.3BSD Reno c w n d s s t h re s h cwud ( ) ssthresh 21-8 c w n d 3 2 s s t h re s h 1 6 c w n d A C K c w n d 2 2 A C K c w n d 4 A C K A C K c w n d s s t h re s h c w n d 1 s s t h re s h [Jacobson 1990b] 21. 5

237 21 TCP 237 T C P A C K A C K A C K A C K A C K A C K A C K 1 ~ 2 A C K 3 3 A C K A C K A C K 3 67, A C K A C K 1) 3 A C K s s t h re s h c w n d c w n d s s t h re s h 3 2) A C K c w n d 1 1 c w n d 3) A C K c w n d s s t h re s h 1 A C K 1 A C 1 A C K c w n d s s t h re s h 4.3BSD Ta h o e 4.3BSD Reno 21.8 ( ) t c m d u m p c w n d s s t h re s h M S S 2 56 c w n d s s t h re s h A C K c w n d M S S 512, 768, 1024, S Y N

238 238 TCP/IP S Y N 7 c w n d s s t h re s h 21-2 A C K t c p d u m p 1 : 257 ( 256 ) 1 ~ 256 S Y N s s t h re s h 512 c w n d S Y N A C K ACK 257 c w n d s s t h re s h c w n d 256 ACK 513 ACK 769 c w n d c w n d 1 /c w n 8 85 ACK / 8 ( 21-2) 21-9 c w n d c w n d c w n d

239 21 TCP A C K s s t h re s h A C K c w n d A C K 1 T C P c w n d s s t h re s h 21-7 ( ) cwnd(100 ) ( ) cwnd ( 21-7) c w n d s s t h re s h A C K c w n d A C K s s t h re s h

240 240 TCP/IP 1 c w n d c w n s s t h re s h A C K A C K 64~66, c w n d 1 A C K 72 c w n d s s t h re s h c w n d s s t h re s h c w n d 1280 A C K c w n d s s t h re s h A C K A C K c w n d 65 c w n d , 48, 50, 52, 54, 55, 57, c w n d c w n d c w n d A C K A C K c w n d A C K 3 A C K c w n d c w n d T C P T C RT T 16 1 RT T RT T 5 % r o u t e ( 8 ) M T ICMP T C P I C M T C P I C M P c w n d 1 s s t h re s h

241 21 TCP 241 I C M P T C P 21-1 T C P 9 I C M P I C M P B S D I C M P S L I P I C M P s l i p a i x S L I P s u n n e t b S L I s u n 9. 2 s u n I P I C M P T C I C M P s l i p sock SLIP SLIP b s d i t c p d u m p a i x test line S L I P another line 3 T C P 6 4 ~ s u n I C M P s l i p I b s d i s u n s u n S L I P a i x 16 T C P I C M P line number SLIP TCP

242 242 TCP/IP 1 SLIP SLIP SLIP TCP ICMP I C M P T C P S L I P the last line T C P ~ 43 s o c k U n i x I C M P 6-12 T C P I C M P 22 ~ 46 6 ~ ~ 19 T C P 3 6, 12, 24, 48 64

243 21 TCP T C P T C M S S T C P s o c k bsdi % sock svr4 discard hello there line number 2 and t c p d u m p TCP 1 2 hello there A C K line number and A C K T C P 1 S Y N T C P RT T RT T K a r n RT T

244 244 TCP/IP 1 3 T C P TCP RT T I C M P T C P T C P I C M P T C P S Y N S V R 4 6, 12, T C P T F T P RT T T F T P A C K A C K A C K BSD Ta h o e E T C P p e r- r o u t e

245 22 TCP 22.1 T C P T C P A C K 9 A C K T C P A C K T C P A C K 0 (persist timer) ( w i n d o w p r o b e ) 22.2 s o c k - P svr4 % sock -i -s -P b s d i t c p d u m p 1 ~ S V R 4 T C P (stream subsystem) T C P

246 246 TCP/IP , 12, 24, T C P 500 ms 4 ms ms T C P ~ T C P 0 A C K T C P T C P S W S

247 22 TCP 247 (Silly Window Syndrome [Clark 1982] 1) 0 M S S 2) ( a ) ( b ) ( c A C K N a g l e ( b ) 1 ( c ) N a g l e ( c ) N a g l e ( a ) ( b ) 2 ( b ) s u n s o c k sun % sock -i -n6 bsdi 7777 b s d i bsdi % sock -i -s -P4 -p2 -r t c p d u m p %

248 248 TCP/IP 1 t c p d u m p b s d i S Y N A C K A C K 1 ~

249 22 TCP 249 ( 22-2) TCP TCP ( E O F ) A C K 0 T C P 20. 3

250 250 TCP/IP A C K F I N F I E S TA B L I S H E D F I N _ WA I T _ 1 F I N _ WA I T _ F I N F I N 19 F I N A C K T C P T C P T C P 21 T C P T C P , A C K ms

251 23 TCP 23.1 T C P / I P T C T C P T C B G P 30 T C P T C P Host Requirements RFC 3 (1) 2 3 T C P T C P R l o g i n Te l n e t T C P / I P Te l n e t 18-16

252 252 TCP/IP N F S T C P 26 Te l n e t R l o g i n 4 1) T C P 2 2) T C P ) 4) 2 T C P 4 2 T C P F I N F I N T C P 1 T C P T C P I C M P 4 E Host Requirements RFC

253 23 TCP b s d i s o c k s v r 4 - K T C P 2 T C P bsdi % sock -K svr4 echo hello, world hello, world -K 4 read error: Connection timed out t c p d u m p Hello, world T C P A R P A R P

254 254 TCP/IP t c p d u m p S Y N F I N R S T T C P B S D 4.3BSD 4.2BSD T C P A R T C P bsdi % sock -K svr4 echo hi, there hi, there read error: Connection reset by peer -K t c p d u m p ~

255 23 TCP 255 s l i p S L I P v a n g o g h. c s. b e r k e l e y. e d u bsdi % sock -K vangogh.cs.berkeley.edu echo t e s t i n g testing read error: No route to host S L I P b s d i t c p d u m p ~ s u n n e t b S L I P 6 s u n I C M P s l i p T C P I C M P I C M P

256 24 TCP 24.1 T C P 1200 b/s S L I P 80 9 T C P / I P T C T 2 F D D I T C P T C P T C M T U T C P T C P 536 M T U (long fat pipe) T C P T C P T C P T C P RT T RFC 1323 [Jacobson, Braden, and Borman 1992] T / T C P T C P T / T C P 4 RT T M T U T / T C P T C P I C M P M T U T C P 24.2 MTU 2. 9 M T U M T U M T U I P D F I P I P D F M T U I C M P t r a c e r o u t e M T U U D P M T U R F C 1191 [Mogul and Deering 1990] T C P Solaris 2.x MTU

257 24 TCP 257 T C P M T U T C P M S S M T U M T T C P M S S M S S M T U T C P I P D F D F I C M P I C M P T C P I C M P M T U I P T C P I C M P M T U 2-5 I C M P M T U M S S M T U RFC Solaris M S S 536 M T U M T M T U M T U M T U M T U M S S M T U I P T C P E M S S M T U M T U M T tcpdump TCP 24-1 MTU s o l a r i s M T U s l i p U D P M T U s l i p M T U s l i p 512 M S S b s d i S L I P M T U T C P s o l a r i s M T U s o l a r i s s o c k s l i p 512

258 258 TCP/IP 1 solaris % sock -i -n1 -w512 slip discard s u n S L I P t c p d u m p 24-2 MTU t c p d u m p 1 2 M S S s o l a r i s 512 S Y N S Y N 4 I C M P b s d i M T U I C M P s o l a r i s F I N 5 s l i p b s d i I C M P s o l a r i s s o l a r i s b s d i M T U D F s o l a r i s [Mogul 1993, ] [Bellovin 1993] T b/s I P I P R 1 R 4

259 24 TCP ( ) 8 b/ =21.4 ms/ b/s ( T C P I P 40 ) ( ) 8 b/ =2.9 ms/ b/s =52.2 ms ms [Bellovin 1993] c a p a c i t y (b) = b a n d w i d t h (b/s) ro u n d-t r i p t i m e ( s ) T C P 24-5

260 260 TCP/IP 1 T1 T1 T3 gigabit (b/s) RTT(ms) ( ) 24-5 Long Fat Network L F N e l e f a n ( t ) s L F N T C P RT T 1) T C P 16 bit ) L F N RT T RFC 1072 [Jacobson and Braden 1988] S A C K RFC 1323 T C P 3) T C P RT T RT T L F N RT T ) T C P 32 bit I P T T L I P M S L M S M S L M S L 3 0 L F N T C P N N M S L M S L 60 T 3 45 Mb/s 12 F D D I 100 Mb/s Mb/s 34

261 24 TCP T C P PAW S (Protection Against Wrapped Sequence numbers) 4. 4 B S D [Partridge 1994] [Kleinrock 1992] ms 24-6 T b/s 1 Gb/s x y ms 8 ms b/s 1Gb/s ms ms 30 ms 1 T ms T T b/s ms 8 ms 2000 Mb/s ms 30 4 m s 10

262 262 TCP/IP T C P 16 bit 32 bit T C P T C P 16 bit 16 ( s c a l i n g o p e r a t i o n ) T C P 32 bit S Y N S Y N S Y N S Y N 0 Host Requirements RFC T C P S Y N T C P S R 16 bit R 32 bit S T C P 16 bit T C P B S D v a n g o g h. c s. b e r k e l e y. e d u s o c k T C P t c p d u m p 2 8

263 24 TCP v a n g o g h S Y N 1 v a n g o g h b s d i S Y N 2 v a n g o g h v a n g o g h A C K RT T A C K T C P A C K RT T 8 RT T RFC RT T RT T RT T 8 1 / / 100 RT T bit T C P 20 32

264 264 TCP/IP 1 RFC BSD ms ms 44.4 S Y N S Y N T C P A C K A C 1) TCP A C K t s re c e n t A C K l a s t a c k 2) l a s t a c k t s re c e n t 3) t s re c e n t l a s t a c k 1) A C K 1 ~ ~ 2048 ACK 2049 A C K 1 ~ A C K 2) ~ ~ ~ A C K 1 ACK 1025 A C K 1 ACK 1025 A C K 2 ACK RT T A C K 3 A C K RT T RT T

265 24 TCP PAWS T C P G t c p d u m p J : K J K bit D E B E M S L T T L bit E PAW S PAW S T/TCP TCP T C P ( t r a n s a c t i o n ) 1) 2) RT T S P T RTT (Round-Trip Ti m e ) SPT (Server Processing Ti m e ) 3) 14 D N S

266 266 TCP/IP 1 T C P U D P T C P U D P U D T C P T / T C P RFC 1379 [Braden 1992b] [ B r a d e n c ] T C P S Y N F I N 2 RT T S P T S Y N F I N T C P T C P T I M E _ WA I T 2 M S L T C P WA I T _ T I M E T / T C P 1) 32 bit CC (Connection Count) C C 1 2) T / T C P T C C C 6 32 bit C C 3) C C S Y N 4) S Y N C C C C C C S Y N C C C T C P 5) S Y N S Y N A C K C C E C H O C C 6) S Y N C C C C RT T T I M E _ WA I T T I M E _ WA I T I M E _ WA I T 8 RTO ) S Y N F I N C C T C P C C C C 2) S Y N F I N F I N

267 24 TCP 267 A C K C C C C C C E C H O T C P F I N A C K S Y N F I N T C P 3) F I N A C K S Y N F I RT T S P T T C P S Y N A C K 2 S Y N A C K S Y N T / T C P A P I F I N F I N M S S 1 M S S 5 36 M S S C C T / T C P RT T RT T RT T T / T C P T C P V M T P Versatile Message Tr a n s a c t i o n P r o t o c o l RFC 1045 [Cheriton 1988] T / T C P V M T P I P V M T P 24.8 TCP ACK ( ) ( 8 0 T C P ~ IP TCP [Stevens 1990] CRC (9.6ms) 10 Mb/s 24-9 T C P [ Wa r n o c k

268 268 TCP/IP ] 24-9 A C K C R C 9. 6 m s 10 Mb/s 12 A C K B b/s throughput= = B/S B+84 B 8 b/b T C P A C K A C K A C K [ Warnock 1991] / 90 F D D I 100 Mb/s[Schryver 1993] F D D I T C P 80 Mb/s~90 Mb/s [Borman 1992] Gray Y- M P 800 Mb/s H I P P I 781 Mb/s Gray Y- M P 907 Mb/s [Borman 1991] 1) 2) T C P [Dalton et al. 1993] [Partridge and Pink 1993] U D P U D P 30 3) RT T T C P T C [Partridge and Pink 1993] B b/s throughput= B+84 B 8 b/b = B/S T C P M T U T C P

269 24 TCP 269 M T U M T U T C P 536 T C P PAW S T C P T C P T / T C P / T I M E _ WA I T S Y N F I N T C P T C T C P S Y N b s d i v a n g o g h 3 16 bit M S L 2? 24.5 PAW S T C P PAW 2 M S L ( T I M E _ WA I T ) s o c k I P 24.7 M S S K a r n T C P S Y N T C P? T / T C P F I N RT T S P T T / T C P RTO T / T C P

270 25 SNMP: 25.1 T C P / I P m a n a g e r X T C P / I P ( a g e n t ) ( ) I C M P IP TTL 64 T C P / I P 3 1) M I B Management Information Base RFC 1213 [McCloghrie and Rose 1991] M I B M I B - I I 2) M I B S M I Structure of Management Information RFC 1155 [Rose and McCloghrie 1990] S M I 0~ ) S N M P Simple Network Management Protocol RFC 1157 [Case et al. 1990] S N M P S N M P U D R F C S N M P SNMP v1 S N M P 1993 S N M P R F C R F C S N M P S N M P SNMP v I P U D P T C P 25.2 S N M P 5

271 25 SNMP 271 1) g e t - r e q u e s t 2) g e t - n e x t - r e q u e s t n e x t 3) s e t - r e q u e s t 4) g e t - r e s p o n s e 3 5) t r a p 3 3 g e t g e t - n e x t s e t SNMP SNMP UDP 161 UDP 161 UDP 161 UDP SNMP S N M P U D P 3 U D P 1 61 Tr a p U D P U D P 5 S N M P I P U D P S N M A S N. 1 B E R A S N. 1 B E 0 S N M P 1 0 SNMP v P D U P D U p u b l i c g e t g e t - n e x t s e t g e t - r e s p o n s e U D P 14-3 D N S 16-2

272 272 TCP/IP 1 IP UDP SNMP SNMP get/set get/set IP UDP P D U (0) ( 0-3 ) ( 0-5 ) 208 P D U t r a p ( 4 ) ( 0-6 ) t r a p 25-2 SNMP PDU 25-4 n o S u c h N a m e r e a d O n l y b a d V a l u e 25-3 SNMP PDU SNMP set 25-4 SNMP g e t g e t - n e x t s e t g e t g e t - n e x t t r a p P D U 4S N M P t r a p 25.3 S N M P I N T E G E R I P 1 2 U D P T C P OCTER STRING 0 8 bit 0 ~ 255

273 25 SNMP 273 B E R N U L L D i s p l a y S t r i n g 0 8 bit A S C I I A S C I I M I B - I I OBJECT IDENTIFIER N U L L g e t g e t - n e x t N U L L I p A d d r e s s 4 OCTER STRING I P I P P h y s A d d r e s s OCTER STRING 6 C o u n t e r G a u g e ( ), M I B t c p C u r r E s t a b E S TA B L I S H E D C L O S E _ WA I T T C P T i m e T i c k s, M I B s y s U p T i m e S E Q U E N C E C s t r u c t u r e S E Q U E N C E 0 A S N. 1 M I B U d p E n t r y U D P 1) I p A d d r e s s u d p L o c a l A d d r e s s I P 2) I N T E G E R u d p L o c a l P o r t SEQUENDE OF S N M P S E Q U E N C E u d p T a b l e U D P ( l i s t e n e r ) S E Q U E N C E U d p E n t r y 25-5 udplocaladdress IpAddress 0 ~ u d p T a b l e

274 274 TCP/IP 1 S N M P g e t - n e x t g e t s e t D N S 14-1 U n i x r o o t U n i x S N M P M I B i s o. o r g. d o d. i n t e r n e t. m e m t. m i b M I B m i b i s o. o r g. d o d. i n t e r n e t. p r i v a t e. e n t e r p r i s e s A s s i g n e d Number RFC M I B

275 25 SNMP 275 RFC 1213 [McColghrie Rose 1991] M I B - I I 25-6 M I B s y s t e m i n t e r f a c e s a t i p U D P U D P instance identification (lexicographic ordering) M I B M I B 25-6 u d p m i b 25-7 U D P 25-7 UDP UDP UDP UDP ( ) UDP 25-8 UDP 25-8 M I B R / W R / W U D P I N T E G E T U D P u d p T a b l e UDP =<udplocaladdress>.<udplocalport> 25-9 u d p T a b l e S N M P M I B 1

276 276 TCP/IP 1 Case C a s e M I B U D P C a s e UDP Case U D P u d p I n D a t a g r a m s I P U D P U D P u d p I n E r r o r u d p N o P o r t s I P U D P u d p O u t D a t a g r a m s U D P u d p I n D a t a g r a m u d p I n E r r o r u d p N o P o r t s M I B C a s e [Rose 1994] M I B C a s e 25.6 M I B M I S N M P m i b u d p u d p T a b l e u d p E n t r y u d p I n D a t a g r a m s i s o. o r g. d o d. i n t e r n e t. m g m t. m i b. u d p. u d p I n D a t a g r a m s. 0 u d p I n D a t a g r a m s. 0 S N M P IP 25-8 UDP M I B U D P M I B u d p L o c a l A d d r e s s I P u d p L o c a l P o r t U D P 3 1 I P I P

277 25 SNMP I P B O O T P 161 S N M P 520 R I P U D P UDP M I B M I UDP ( ) UDP 1) u d p L o c a l A d d r e s s u d p L o c a l P o r t 2) UDP U D P g e t - n e x t 25.7 S N M P I S O D E s n m p i [Rose 1994]

278 278 TCP/IP U D P - a - c S N M P s n m p i g a t e w a y S n m p i s n m p i > g e t S N M P g e t - r e q u e s t q u i t q u i t t c p d u m p SNMP t c p d u m p U D P U D S N M P 0 g e t - n e x t get-next g e t - n e x t M I B U D P U D P 1 2 g e t - n e x t g e t - n e x t

279 25 SNMP 279 M I B U D P u d p T a b l e u d p T a b l e g e t - n e x t g e t - n e x t s n m p I n P k t s U D P 25.8 M I B M I s y s t e m i f a t i p i c m p t c p s y s t e m s y s t e m s y s t e m UDP n e t b

280 280 TCP/IP 1 R / W s y s D e s c r D i s p l a y S t r i n g s y s O b j e c t I D O b j e c t I D s y s U p Ti m e Ti m e Ti c k s s y s C o n t a c t D i s p l a y S t r i n g s y s N a m e D i s p l a y S t r i n g ( F Q D N ) s y s L o c a t i o n D i s p l a y S t r i n g s y s S e r v i c e s [ ] O S I 0 x 01 ( ) 0 x 02 0 x 04 0 x 08 0 x system 25-6 s y s t e m i n t e r n e t. p r i v a t e. e n t e r p r i s e s Assigned Numbers RFC 12 E p i l o g u e s y s S e r v i c e s 4 8 R / W interface i f N u m b e r I N T E G E R i f s u n 3. 8 S L I P

281 25 SNMP 281 <I f I n d e x> R / W i f I n d e x I N T E G E R 1 i f N u m b e r i f D e s c r D i s p l a y S t r i n g i f Ty p e I N T E G E R 6 = 7 = = = PPP 28 = SLIP, i f M t u I N T E G E R M T U i f S p e e d G a u g e b / s i f P h y s A d d r e s s P h y s A d d r e s s 0 i f A d m i n S t a t u s [ 1 3 ] 1= 2 = 3 = i f O p e r S t a t u s [ 1 3 ] 1= 2 = 3 = i f L a s t C h a n g e Ti m e Ti c k s s y s U p T i m e i f I n O c t e t s C o u n t e r i f I n U c a s t P k t s C o u n t e r i f I n N U c a s t P k t s C o u n t e r i f I n D i s c a r d s C o u n t e r i f I n E r r o r s C o u n t e r i f I n U n k n o w n P r o t o s C o u n t e r i f O u t O c t e t s C o u n t e r i f O u t U c a s t P k t s C o u n t e r i f O u t N U c a s t P k t s C o u n t e r i f O u t D i s c a r d s C o u n t e r i f O u t E r r o r s C o u n t e r i f O u t Q L e n G a u g e i f S p e c i f i c O b j e c t I D M I B i f T a b l e 1 g e t 5 g e t - n e x t g e t - n e x t S L I P S L I S L I P g e t - n e x t next ifdescr a t M I B - I I M I B - I

282 282 TCP/IP 1 I P I i p N e t T o M e d i a T a b l e s n m p i ( d u m p ) k i n e t i c s T C P / I P A p p l e Ta l k A R P <a t I f I n d e x>. 1. <a t N e t A d d re s s> R / W a t I f I n d e x I N T E G E R i f I n d e x a t P h y s A d d r e s s P h y s A d d r e s s 0 a t N e t A d d r e s s N e t w o r k A d d r e s s I P a t T a b l e t c p d u m p s n m p i g e t - n e x t a t g e t - n e x t A p p l e Ta l k a t ARP 32 bit 48 n e t b I P n e t b k i n e t i c s k i n e t i c s A R P SNMP i p i p

283 25 SNMP 283 R / W i p F o r w a r d i n g [ 1 2 ] 1 I P 2 i p D e f a u l t T T L I N T E G E R T T L T T i p I n R e c e i v e s C o u n t e r I P i p I n H d r E r r o r s C o u n t e r T T L i p I n A d d r E r r o r s C o u n t e r I P i p F o r w D a t a g r a m s C o u n t e r I P i p I n U n k n o w n P r o t o s C o u n t e r I P i p I n D i s c a r d s C o u n t e r i p I n D e l i v e r s C o u n t e r I P i p O u t R e q u e s t s C o u n t e r I P I P i p F o r w D a t a g r a m s i p O u t D i s c a r d s C o u n t e r i p O u t N o R o u t e s C o u n t e r i p R e a s m Ti m e o u t I N T E G E R i p R e a s m R e q d s C o u n t e r I P i p R e a s m O K s C o u n t e r I P i p R e a s m F a i l s C o u n t e r I P i p F r a g O K s C o u n t e r I P i p F r a g F a i l s C o u n t e r I P i p F r a g C r e a t e s C o u n t e r I P i p R o u t i n g D i s c a r d s C o u n t e r i p i p I P I P I P <i p A d E n t A d d r> R / W i p A d E n t A d d r I p A d d r e s s I P i p A d E n t I f I n d e x I N T E G E R i f I n d e x i p A d E n t N e t M a s k I p A d d r e s s I P i p A d E n t B c a s t A d d r [ 0 1 ] I P 1 i p A d E n t R e a s m M a x S i z e [ ] I P IP i p A d r T a b l e s u n I P

284 284 TCP/IP 1 SLIP I P 3. 8 i f c o n f i g i p I P I P R / W i p R o u t e D e s t I p A d d r e s s I P i p R o u t e I f I n d e x I N T E G E R i f I n d e x i p R o u t e M e t r i c 1 I N T E G E R i p R o u t e P r o t o 1 i p R o u t e M e t r i c 2 I N T E G E R i p R o u t e M e t r i c 3 I N T E G E R i p R o u t e M e t r i c 4 I N T E G E R i p R o u t e N e x t H o p I p A d d r e s s I P i p R o u t e T y p e I N T E G E R 1 = 2 = 3 = 4 = i p R o u t e P r o t o I N T E G E R 1 = 4 = ICMP 8 = RIP, 13 = OSPF, 14 = BGP, i p R o u t e A g e I N T E G E R i p R o u t e M a s k I p A d d r e s s i p R o u t e D e s t I P i p R o u t e M e t r i c 5 I N T E G E R i p R o u t e I n f o O b j e c t I D M I B IP i p R o u t e T a b l e s n m p i dump iproutetable s u n 5 1 i p R o u t e (4) (1) (3) (1) (3) (1) (3) (1) (4) (1) s u n IP

285 25 SNMP 285 n e t s t a t n e t s t a t i p a t I P I P <i p N e t To M e d i a I f I n d e x>. <i p N e t To M e d i a N e t A d d re s s> R / W i p N e t To M e d i a I f I n d e x I N T E G E R i f I n d e x i p N e t To M e d i a P h y s A d d r e s s P h y s A d d r e s s i p N e t To M e d i a N e t A d d r e s s I p A d d r e s s I P i p N e t To M e d i a Ty p e [ 1 4 ] 1 = 2 = 3 = 4 = IP i p N e t T o M e d i a T a b l e s u n A R P sun % arp -a svr4 ( ) at 0:0:c0:c2:9b:26 bsdi ( ) at 0:0:c0:6f:2d:40 S N M P i c m p i c m p 4 I C M P I C M 22 I C M P I C M P S N M P t c p t c p T C P

286 286 TCP/IP 1 R / W i c m p I n M s g s C o u n t e r I C M P i c m p I n E r r o r s C o u n t e r I C M P I C M P i c m p I n D e s t U n r e a c h s C o u n t e r I C M P i c m p I n T i m e E x c d s C o u n t e r I C M P i c m p I n P a r m P r o b s C o u n t e r I C M P i c m p I n S r c Q u e n c h s C o u n t e r I C M P i c m p I n R e d i r e c t s C o u n t e r I C M P i c m p I n E c h o s C o u n t e r I C M P i c m p I n E c h o s R e p s C o u n t e r I C M P i c m p I n T i m e S t a m p s C o u n t e r I C M P i c m p I n T i m e S t a m p R e p s C o u n t e r I C M P i c m p I n A d d r M a s k s C o u n t e r I C M P i c m p I n A d d r M a s k R e p s C o u n t e r I C M P i c m p O u t M s g s C o u n t e r I C M P i c m p O u t E r r o r s C o u n t e r I C M P I C M P i c m p O u t D e s t U n r e a c h s C o u n t e r I C M P i c m p O u t T i m e E x c d s C o u n t e r I C M P i c m p O u t P a r m P r o b s C o u n t e r I C M P i c m p O u t S r c Q u e n c h s C o u n t e r I C M P i c m p O u t R e d i r e c t s C o u n t e r I C M P i c m p O u t E c h o s C o u n t e r I C M P i c m p O u t E c h o s R e p s C o u n t e r I C M P i c m p O u t T i m e S t a m p s C o u n t e r I C M P i c m p O u t T i m e S t a m p R e p s C o u n t e r I C M P i c m p O u t A d d r M a s k s C o u n t e r I C M P i c m p O u t A d d r M a s k R e p s C o u n t e r I C M P i c m p R / W t c p R t o A l g o r i t h m I N T E G E R 1 = 2 = RTO, 3 = MIL S T D B, 4 = Van Jacobson t c p R t o M i n I N T E G E R t c p R t o M a x I N T E G E R t c p M a x C o n n I N T E G E R T C P 1 t c p A c t i v e O p e n s C o u n t e r C L O S E D S Y N _ S E N T t c p P a s s i v e O p e n s C o u n t e r L I S T E N S Y N _ R C V D t c p A t t e m p F a i l s C o u n t e r S Y N _ S E N T S Y N _ R C V D C L O S E D, S Y N _ R C V D L I S T E N t c p E s t a b R e s e t s C o u n t e r E S TA B L I S H E D C L O S E _ WA I T C L O S E D t c p C u r r E s t a b G a u g e E S TA B L I S H E D C L O S E _ WA I T t c p I n S e g s C o u n t e r t c p O u t S e g s C o u n t e r t c p R e t r a n s S e g s t c p I n E r r s C o u n t e r t c p O u t R s t s C o u n t e r R S T t c p

287 25 SNMP 287 s u n t c p S u n O S Van Jacobson 200 ms~12.8 s T C P 12.8 s s t c p T C P T C P 5 I P I <t c p C o n n L o c a l A d d re s s>. <t c p C o n n L o c a l P o rt>. <t c p C o n n R e m A d d re s s>. <t c p C o n n R e m P o rt> R / W t c p C o n n S t a t e [ ] 1 = CLOSED, 2 = LISTEN, 3 = SYN_SENT, 4 = SYN_RCVD, 5 = ESTABLISHED, 6 = FIN_WAIT, 7 = FIN_WAIT, 8 = CLOSE_WAIT, 9 = LAST_ACK, 10 = CLOSING, 11 = T I M E _ WA I T, 12 = T C B 12 t c p C o n n L o c a l A d d r e s s I p A d d r e s s I P t c p C o n n L o c a l P o r t [ ] t c p C o n n R e m A d d r e s s I p A d d r e s s I P t c p C o n n R e m P o r t [ ] TCP t c p C o n T a b l e s u n T C P sun % rlogin gemini g e m i n i I P sun % rlogin localhost I P F T P 21

288 288 TCP/IP 1 r l o g i n g e m i n i g e m i n i 1023 Te l n e t F T P I S N M P MTU n e t b s u n S L I P M T U S N M P M T U I P S L I i p R o u t e I f I n d e x S L I P M T U S L I P S L I P M T U D N S 1 I P I S N M P I P g e m i n i Te l n e t

289 25 SNMP 289 t r a c e r o u t e t r a c e r o u t e g e m i n i s w n r t n e t b A R P s u n s u n n e t b S L I P Te l n e t g e m i n i n e t b 8. 5 t r a c e r o u t e s w n r t t r a c e r o u t e s w n r t 2 I C M P t r a c e r o u t e g e m i n i TTL 3, 4 5 n e t b s w n r t S N M P n e t b n e t b s w n r t g e m i n i g e t

290 290 TCP/IP 1 sun % snmpi -a netb -c secret get iproutenexthop i p R o u t e N e x t H o p = n e t b s w n r t g e m i n i n e t b g e m i n i g e m i n i g e m i n i s w n r t Trap t r a p 25-1 t r a p trap PDU t c p d u m p 6 t r a p 7 t r a p t r a p t r a p t r a p 0 c o l d S t a r t 1 w a r m S t a r t 2 l i n k D o w n l i n k U p a u t h e n t i c a t i o n F a i l u r e S N M P 5 e g p N e i g h b o r L o s s E G P I P 6 e n t e r p r i s e S p e c i f i c t r a p trap t c p d u m p t r a p s u n S N M P c o l d S t a r t t r a p t r a b s d i t r a p t c p d u m p 25-1 t r a p t r a p s n m p i a u t h e n t i c a t i o n F a i l u r e t r a p t c p d u m p SNMP trap U D P S N M P 161 s n m p 162 s n m p - t r a p C = t r a p s t r a p ISODE SNMP

291 25 SNMP Tr a p Tr a p 2 9 P D U E : u n i x s y s O b j i e c t I D i s o. o r g. d o d. i n t e r n e t. p r i v a t e. e n t e r p a r s e s u n i x. a g e n t s. f o u r B S D - i s o d e. 5 I S O D E t r a p I P t r a p c o l d S t a r t 2 a u t h e n t i c a t i o n F a i l u r e t r a p t r a p T i m e T i c k s t r a p t r a t r a p 200 ms t c p d u m p 2 t r a 1 t r a p s ms t r a p ASN.1 BER S N M P A S N. 1 Abstract Syntax Notation 1 S N M P B E R Basic Encoding Rule S N M P A S N. 1 B E R S N M P [Rose 1990] 8 A S N. 1 B E R A S N. 1 M I B S N M P A S N. 1 S M I i p A d d r e s s A S N. 1 IpAddress ::= [APPLICATION 0] -- in network-byte order IMPLICIT OCTET STRING (SIZE (4)) M I B S E Q U E N C E SEQUENCE OF A S N. 1 S N M P B E R 64 B E 3 1 A S N. 1 B E R S N M P

292 292 TCP/IP SNMPv S N M P 11 R F C RFC 1441 [Case et al. 1993] S N M P v 2 [Stallings 1993; Rose 1994] S N M P v 2 S N M P v 2 B. 3 [Rose 1994] 1994 S N M P v 1 S N M P v 2 1) S N M P v 2 g e t - b u l k - r e q u e s t 2) i n f o r m - r e q u e s t 3) M I B SNMPv2 MIB SNMPv2-M2M MIB M I B 4) SNMPv2 S N M P v 1 S N M P v 1 SNMP v2 S N M P v 2 S N M P [Routhier 1993] S N M P v 1 S N M P v S N M P S N M P S N M P - M I B S N M P S N M P S N M P g e t - n e x t S N M P S N M P s y s t e m i n t e r f a c e address translation I P I C M P T C P U D P M T U S N M P t r a p A S N. 1 B E R S N M P S N M P 25.1 U D P g e t - n e x t

293 26 Telnet Rlogin 26.1 Remote Login I n t e r n e t T C P / I P 1) Te l n e t T C P / I P Te l n e t 2) Rlogin U n i x U n i x Te l n e t R l o g i n R l o g i n R l o g i n Te l n e t I n t e r n e t 1969 A R PA N E T telecommunication network protocol 26-1 Te l n e t R l o g i n Telnet Telnet shell TCP Telnet 1) Te l n e t T C P / I P T C P 2) Te l n e t pseudo-terminal device U n i x ( s h e l l ) Te l n e t

294 294 TCP/IP 1 3) T C P Te l n e t R l o g i n 4) 26-1 T C P / I P Te l n e t 5) Te l n e t R l o g i n Te l n e t R l o g i n 26-2 Te l n e t R l o g i n Telnet Telnet Rlogin Rlogin 26-2 Telnet/ Rlogin/ / Te l n e t Te l n e t Te l n e t R l o g i n [Paxson 1993] 1 : Rlogin R l o g i n 4. 2 B S D U n i x R l o g i n Te l n e t R l o g i n U n i x RFC 1282 [Kantor 1991] R l o g i n R I P R F C R l o g i n [Stevens 1990] 15 R l o g i n [ C o m e r Stevens 1993] Te l n e t

295 26 Telnet Rlogin R l o g i n T C P T C P 1) 4 a 0 b 0 c 0 d / 0 v i 2) 0 3) password: 60 (home directory). r h o s t s [Curry 1992] R l o g i n 4. 4 B S D K e r b e r o s K e r b e r o s K e r b e r o s [Curry 1992] K e r b e r o s 4) N a g l e T C P R l o g i n S TO P START A S C I I C o n t r o l S C o n t r o l Q C o n t r o l _ S

296 296 TCP/IP Rlogin Rlogin Control_S 26-3 STOP/START C o n t r o l _ S C o n t r o l _ S C o n t r o l _ Q e m a c s C o n t r o l _ S C o n t r o l _ C D E L E T E C o n t r o l _ C 26-3 T C P C o n t r o l _ S T C P u rgent mode U n i x R l o g i n T C P R l o g i n 4 T C P T C P T C P (flush output)

297 26 Telnet Rlogin x 0 2 ( p e n d i n g o u t p u t ) 0 x x x Rlogin x T C P 0 x ff A S C I I s 4 16 bit 25 80X Y 16 b i t 0 R l o g i n in-band signaling 0 x ff 0 x ff R l o g i n 0 x ff A S C I I s R l o g i n A P I out-of-band data (out-of-band signaling) T C P 0 x ff

298 298 TCP/IP 1 1 : R l o g i n R l o g i n ( t i l d e ) ~ 4 1) 2) C o n t r o l _ D 3) C o n t r o l _ Z 4) C o n t r o l _ Y U n i x 26.3 Rlogin R l o g i n 19-2 R l o g i n b s d i s v r 4 R l o g i n ( T C P 1 ~ r s t e v e n s r s t e v e n s i b m p c 3 / T C P ( S V R 4 ) x ff 2 s4 16 bit 4 10, 12, ( g r e e t i n g ) 18 7 s v r R l o g i n ~

299 26 Telnet Rlogin I A N A 1. 9 R l o g i n 1024 U n i x [ S t e v e n s ] x80: shell 26-5 Rlogin T C P T C P s u n b s d i C o n t r o l _ S D E L E T E

300 300 TCP/IP 1 sun % rlogin bsdi bsdi % cat /usr/share/misc/termcap C o n t r o l _ S ^? bsdi % 1) C o n t r o l _ S 2) R l o g i n 3) T C P 4) T C P T C P 0 5) 0 6) R l o g i n R l o g i n c a t 7) c a t c a 8) c a t T C P T C P 9) c a t R l o g i n R l o g i n R l o g i n 0 x Rlogin 4096 Rlogin 4096 Rlogin Rlogin 26-6 Rlogin ~ T C P 4 A C K A C K

301 26 Telnet Rlogin A C K A C K c a t T C P 10 0 x T C P 11 0 T C P 26-7 Rlogin

302 302 TCP/IP 1 R l o g i n T C P 13 14, 15, ^? Telnet Te l n e t RFC 854 [Postel Reynolds 1983a] N V T Network Virtual Te r m i n a ln V T N V T N V T N V T N V T NVT ASCII NVT ASCII 7 A S C I I NVT ASCII C R L F \ r \ n C R C N U L 0 \ r \ 0 F T P, SMTP, Finger W h o i s NVT ASCII Telnet Te l n e t 0 x f f I A C interpret as command N V T A S C I I 7 b i t 255 Te l n e t Te l n e t R F C 856 [ P o s t e l Reynolds 1983b] 8 b i t 26-8 Te l n e t

303 26 Telnet Rlogin 303 ( ) E O F S U S P A B O RT E O R S E N O P D M B R K I P A O AY T E C E L G A S B W I L L W O N T D O D O N T I A C IAC 255 Telnet Te l n e t N V T Te l n e t 1. W I L L 4 D O 2. W I L L 1) WILL D O N T 3. D O ( e n a b l e ) W I L L 2) DO 4. D O W O N T 5. W O N T 3) WONT D O N T 6. D O N T 4) DON T W O N T Te l n e t 26-9 Telnet I A C WILL, DO, WONT D O N T

304 304 TCP/IP 1 I D ( ) R F C 40 A s s i g n e d Number RFC R F C Te l n e t Te l n e t Te l n e t Telnet A S C I I R F C [ VanBokkelen 1989] 3 <IAC, WILL, 24> 24 I D <IAC, DO, 24> <IAC, SB, 24, 1, IAC, SE> S B 24 S B 1 I A C S B i b m p c IAC, SB, 24, 0 I, B, M, P, C, IAC, SE 4 0 Assigned Numbers RFC U n i x t e r m c a p t e r m i n f o Te l n e t Te l n e t 4 1.

305 26 Telnet Rlogin 305 Te l n e t N V T GO AHEAD G A N V T N V T RFC 857 [Postel Reynolds 1983c] E C H O RFC 858 [Postel Reynolds 1983d] SUPPRESS GO AHEAD 2. R l o g i n Te l n e t SUPPRESS GO AHEAD DO SUPPRESS GO AHEAD WILL SUPPRESS GO AHEAD WILL ECHO 3. kludge line mode RFC 858 R F C E C H O SUPPRESS GO AHEAD Te l n e t 4. RFC 1184[Borman 1990] Te l n e t Te l n e t c h a r k l u d g e l i n e m o d e RFC Telnet B S D / B S D

306 306 TCP/IP Te l n e t Data Mark 26-8 D M T C P D M Te l n e t Te l n e t D M T C P T C P T C P Te l n e t Te l n e t R l o g i n Te l n e t C o n t r o l _] c o n t r o l ^ ] t e l n e t > U n i x h e l p 26.5 Telnet Te l n e t R l o g i n B S D / 386 S V R 4 t c p d u m p S E N T R C V D 1) SUPPRESS GO AHEAD GO AHEAD D O G A 10 2) RFC 1091[VanBokkelen 1989] U n i x W I L L

307 26 Telnet Rlogin Telnet 3) NAW S RFC 1073 [Wa i t z m a n ] R l o g i n 0 x 80 4) TSPEED RFC 1079 [Hedrick 1988b] 12 5) LFLOW RFC1371 [Hedrick Borman 1992] 13 C o n t r o l _ S C o n t r o l _ Q 26-4 R l o g i n 0 x 10 0 x 20 R l o g i n 6) LINEMODE Te l n e t 14 7) ENVIRON RFC 1408 [Borman

308 308 TCP/IP a ] 15 U n i x BSD/386 Te l n e t D I S P L AY P R I N T E R Te l n e t 8) STAT U S RFC 859 [Postel Reynolds 1983e] Te l n e t D O 16 9) U n i x 17 10) GO AHEAD 11) 12) 13) 14) 15) 16) 17) 18) I B M P C ) 20) 21) U n i x Te l n e t 4. 2 B S D B S D WILL ECHO 4. 2 B S D T C P T C 22) WONT ECHO 4. 2 B S D 23) WONT ECHO DONT ECHO ~ Te l n e t T C P DO TERMINAL TYPE ~ ~ Te l n e t 47 Te l n e t 6 WILL ECHO DO ECHO

309 26 Telnet Rlogin 309 \r\n\r\nunix(r) System V Release 4.0 (svr4) \r\n\r\0\r\n\r\0 4 \ r \ n Te l n e t \ r \ 0 Te l n e t I A C Telnet l o g i n : R l o g i n Te l n e t d a y t i m e ( e c h o ) T C P

310 310 TCP/IP U n i x Te l n e t 23 Te l n e t N V T Te l n e t ( d i s c a r d ) FTP SMTP Te l n e t b s d i v a n g o g h. v s. b e r k e l e y. e d u 4. 4 B S D B S D / B S 1) B S D / B S D 2) 4. 4 B S D B S D / 386 3) WILL LINEMODE DO LINEMODE 16 Te l n e t C o n t r o l _ C C o n t r o l _ C C o n t r o l _ C Te l n e t I P <IAC, IP> 4) R l o g i n Te l n e t (a) WILL ECHO (b) DO ECHO (c) P a s s w o r d: (d) R E T U R N (e) R E T U R N C R L F (f) WONT ECHO (g) DONT ECHO

311 26 Telnet Rlogin Vangogh % d a t e Telnet R l o g i n 19-2 Te l n e t 2 A C K I P T C P 86 R l o g i n A C K 611 v i 1) Te l n e t WILL ECHO 2) DO ECHO 3) N a g l e 4) Te l n e t WONT ECHO 5) DONT ECHO R l o g i n Te l n e t

312 312 TCP/IP 1 R l o g i n Te l n e t Te l n e t Te l n e t Te l n e t v i Rlogin Telnet (Kludge line mode) Te l n e t B S D / 386 1) DO TIMING M A R K RFC 860 [Postel Reynolds 1983f] Te l n e t 2) WILL TIMING MARK 3) WONT SUPPRESS GO AHEAD WONT ECHO SUPPRESS GO AHEAD E C H O 4) DONT SUPPRESS GO AHEAD DONT ECHO 5) l o g i n : 6) P a s s w o r d : WILL ECHO DO ECHO 7) 8) WONT ECHO DONT c h a r sun svr 4 Control Telnet ( )

313 26 Telnet Rlogin 313 WONT Te l n e t SUPPRESS GO AHEAD E C H O v i 1) WILL SUPPRESS GO AHEAD WILL ECHO 2) DO SUPPRESS GO AHEAD WILL ECHO 3) 4) WONT SUPPRESS GO A H E A D WONT ECHO 5) DONT SUPPRESS GO AHEAD DONT ECHO SUPPRESS GO AHEAD E C H O SUPPRESS GO AHEAD E C H O v i Telnet Te l n e t b s d i c a n g o g h. c s. b e r k e l e y. e d u Te l n e t C o n t r o l _ C D E L E T E Te l n e t I P <IAC, IP> 3 <IAC, DO, TM> Te l n e t DO TIMING MARK W I L L W O N T Te l n e t 1 T C P Host Requirements RFC I P Te l n e t <IAC, IP> <IAC, DM> D M Unix Telnet I P

314 314 TCP/IP DO TIMING MARK 3 4 Te l n e t <IAC, DM> 3 4 D M 1 I P T C P R l o g i n T C P R F C Te l n e t 1 1 D M I A C D M R l o g i n Te l n e t R l o g i n U n i x 1 Te l n e t Te l n e t Te l n e t Te l n e t R l o g i n Te l n e t

315 26 Telnet Rlogin Rlogin Telnet R l o g i n Te l n e t T C P T C P 23 T C P R l o g i n Te l n e t T C P T C P A C K K e r b e r o s 26.3 R l o g i n 1. 9 R l o g i 512 ~ RFC 1097 Te l n e t ( s u b l i m i n a l - m e s s a g e )

316 27 FTP 27.1 F T P I n t e r n e t file transfer (file access) F T P N F S S u n 29 F T P F T P F T P Te l n e t F T P Te l n e t 7 A S C I I N V T F T P F T P A S C I I 959 [Postel Reynolds 1985] F T P 27.2 FTP F T P T C 1) F T P 21 T C P 2 I P 2) I P F T P F T P

317 27 FTP 317 ( F T P ) ( F T P ) (a) ASCII NVT ASCII NVT ASCII NVT ASCII NVT ASCII C R L F T F I P A S C I I (b) EBCDIC E B C D I C (c) (d) 8 bit 8 bit 2. A S C I I E B C D I C (a) (b) (c) Fortran F o r t r a n 3. a b A S C I I E B C D I C c TO P S - 20 R F C 4. a b c

318 318 TCP/IP 1 0 F T P 72 U n i x FTP A S C I I A S C I I R F C R F C U n i x U n i x F T P R F C F T P F T P FTP NVT ASCII C R L F Te l n e t I A C < I A C, I P > Te l n e t < I A C, D M > Te l n e t Te l n e t W I L L W O N T D O D O N T DONT W O N T 3 4 A S C I I F T P A B O R LIST f i l e l i s t PASS p a s s w o rd P O RT n1,n2,n3,n4,n5,n6 Q U I T RETR f i l e n a m e S TOR f i l e n a m e S Y S T TYPE t y p e USER u s e r n a m e F T P I P n1.n2.n3.n4 n n6 A A S C I I I 27-2 FTP F T P F T P

319 27 FTP FTP A S C I I S M T P y z 2 y z 3 y z 4 y z 5 y z x 0 z x 1 z x 2 z x 3 z x 4 z x 5 z M O D E ( ) F T P Q U I T 221 Goodbye HELP

320 320 TCP/IP ) 2) 3) F T P U n i x 1) 2) 3) P O RT 4) P O RT 6 A S C I I 4 I P bit 16 bit = FTP IP FTP IP FTP FTP PORT SYN , 1174 FTP FTP

321 27 FTP 321 P O RT FTP F T P NVT ASCII F T P Te l n e t F T P F T P F T d d e b u g s v r > 3 f t p > svr4 % ftp -d bsdi Connected to bsdi. -d 220 bsdi FTP server (Version 5.60) ready Name (bsdi:rstevens): ---> USER rstevens R E T U R N 331 Password required for rstevens. P a s s w o r d : ---> PASS XXXXXXXX 230 User rstevens logged in. ftp> dir hello.c ---> PORT 140,252,13,34,4, PORT Command successful. ---> LIST hello.c 150 Opening ASCII mode data connection for /bin/ls. -rw-r--r-- 1 rstevens staff 38 Jul 17 12:47 hello.c 226 Transfer complete. remote: hello.c 56 bytes received in 0.03 seconds (1.8 Kbytes/s) ftp> q u i t ---> QUIT 221 Goodbye F T P R E T U R N T C P P O RT 1174 d i r F T P P O RT L I S T

322 322 TCP/IP ( TO S ) 3-2 F T P 20 f t p - d a t a P O RT FTP

323 27 FTP FTP P O RT Unix FTP Host Requirements RFC F T P PORT s v r b s d i M S L S O _ R E U S E A D D R 20 2 M S L P O RT s e n d p o r t F T P Unix FTP P O RT L I S T s v r P O RT 1)

324 324 TCP/IP 1 ( 1 LIST ) ( bsdi.ftp-data svr TCP ) ( 2 LIST ) 27-8 LIST 2) 1176 S O _ R E U S E A D D R 3) <svr4, 1176, bsdi, 21> <svr4, 1176, bsdi, 20> b s d i T C P I P I 4 4) 5 2 M S L <svr4, 1176, bsdi, 20> 5) L I S T 1176 S O _ R E U S E A D D R 1176

325 27 FTP 325 6) S O _ R E U S E A D D R 20 2 M S L (socket pair) 4 2 M S L T C P S Y N 2 M S L B S D S V R 4 30 M S L M S L 1 S Y N T C P S Y Host Requirements RFC P O RT 2 M S L NVT ASCII NVT ASCII - d sun % ftp bsdi Connected to bsdi. 220 bsdi FTP server (Version 5.60) ready. Name (bsdi:retevens); 331 Password required for rstevens. Passord : 230 User rstevens logged in. ftp> get hello.c R E T U R N 200 PORT command successful. 150 Opening ASCII mode data connection for hello.c (38 bytes). 226 Transfer complete. 38 local: hello.c remote: hello.c 42 bytes received in seconds (11 Kbytes/s) 42 f t p > q u i t 221 Goodbye. Sun % ls -l hello.c -rw-rw-r-- 1 rstevens 38 Jul 18 08:48 hello.c 38 sun % wc -l hello.c 4 hello.c 4 42 U n i x \ n NVT ASCII 2 \ r \ n A S C I I 1) 2 ) 2 NVT ASCII B S D / 386 d e b u g

326 326 TCP/IP 1 F T P bsdi & ftp -d slip Connected to slip. 220 slip FTP server (Version 5.60) ready. Name (slip:rstevens): ---> USER rstevns 331 Password required for rstevens. Password : - d R E T U R N ---> PASS XXXX 230 User rstevns logged in. ---> SYST 215 UNIX Type: L8 Version : BSD Remote system type is UNIX. Using binary mode to transfer files. ftp> get hello.c ---> TYPE I 200 Type set to I. ---> PORT 140,252,13,66,4,84 = = PORT command successful. ---> RETR hello.c 150 Opening BINARY mode data connection for hello.c (38 bytes). 226 Transefer complete. 38 bytes received in seconds (1.1 Kbytes/s) 38 ftp> q u i t ---> QUIT 221 Goodbye. F T P S Y S T 215 UNIX Type : L8 8 bit U n i x h e l l o. c TYPE I 38 Host Requirements RFC FTP SYST RFC B S D / 386 AIX SunOS Solaris 2.x 500 SVR Telnet F T P A B O R Te l n e t

327 27 FTP 327 ftp> get a.out ---> TYPE I 8 bit U n i x 200 Type set to I. ---> PORT 140,252,13,66,4, PORT command successful. ---> RETR a.out 150 Opening BINARY mode data connection for a.out (28672 bytes). ^? receive aborted waiting for remote to finish abort 426 Transfer aborted. Data connection closed. 226 Abort successful 1536 bytes received in 1.7 seconds (0.89 Kbytes/s) Unix A B O R

328 328 TCP/IP < I A C, I P, I A C, D M, A, B, O, R, \ r, \ n > T C P Te l n e t Host Requirements RFC D M 54 F T P 3 7 BSD FTP F T P A B O R S TAT Te l n e t ~ 5120

329 27 FTP Te l n e t U n i x F T P F T P Te l n e t F T P Te l n e t F T P FTP F T P F T F T P F T P f t p. u u. n e t F T P F T P a n o n y m o u s sun % ftp ftp.uu.net Connected to ftp.uu.net 220 ftp.uu.net FTP server (Version 2.0WU(13) Fri Apr 9 20:44:32 EDT 1993) ready Name (ftp.uu.net:rstevens): a n o n y m o u s 331 Guest login ok, send your complete addraess as password. Password : Welcome to the UUNET archive. r s t e v e n n o a o. e d u 230- A service of UUNET Technologies Inc, Falls Church, Virginia 230- For information about UUNET, call , or see the files 230- in /uunet-info 230 Guest login ok, access restrictions apply. ftp> cd published/books 250 CWD command successful. ftp> b i n a r y 200 Type set to I. ftp> get stevens.tcpipivl.errata.z 200 PORT command successful. 150 Opening BINARY mode data connection for stevens.tcpipivl.errata.z (150 bytes). 226 Transfer complete. ( ) local: stevens.tcpipivl.errata.z remote: stevens.tcpipivl.errata.z 105 bytes received in 4.1 seconds (0.83 Kbytes/s) ftp> q u i t 221 Goodbye. sun % uncompress stevens.tcpipivl.errata.z sun % more stevens.tcpipivl.errata

330 330 TCP/IP 1 F T P Unix compress( 1 ). Z A S C I I IP FTP F T P D N S D N S I P t r a c e r o u t e I P F T P I P I D N S 1) s l i p 2 I P I P n o a o. e d u 2) b s d i S L I P I P ) s u n b s d i 9. 2 I n t e r n e t s l i p g a t e w a y n e t b s u n s u n 3 I n t e r n e t I P F T P

331 27 FTP F T P I n t e r n e t T C P T C P F T P T C T C P P O RT 2 M S L F T P NVT ASCII NVT ASCII U n i x 8 b i t U n i x F T P I n t e r n e t F T P local: hello.c remote: hello.c 42 bytes received in seconds (11 Kbytes/s)

332 28 SMTP: 28.1 e - m a i l [Caceres et al.1991] T C P SMTP (Simple Mail Transfer Protocol) F T P [Paxson 1993] T C P / I P TCP TCP Internet user agent U n i x M H Berkeley Mail, Elm M u s h T C P M TA Message Transfer Agent U n i x M TA S e n d m a i l M TA M TA M TA T C P RFC 821 [Postel 1982] S M T P T C M TA RFC 822 [Crocker 1982] M TA RFC SMTP M TA NVT ASCII F T P 12 F T P S M T P -v

333 28 SMTP 333 S e n d m a i l M TA S M T P > > > S M T P 3 S M T P MTA(Sendmail) 5 S M T P H E L O M A I L R C T P D ATA Q U I T m a i l s u b j e c t M TA M TA T C P n o a o. e d u S e n d m a i l H E L O s u n. t u c. n o a o. e d u M A I L R C P T R C P T D ATA Q U I T S M T P S M T P S M T

334 334 TCP/IP 1 Received: M e s s a g e - I d: M TA 28-2 SMTP SMTP S M T P 8 5 H E L O M A I L R C P T D ATA Q U I T R S E T

335 28 SMTP 335 V R F Y N O O P O K 200 E X P N V R F Y S e n d m a i l 4.4BSD S e n d m a i l 8 V R F Y.forward T U R N T C P S e n d m a i l S E N D S O M L S A M L M A I L ) e n v e l o p e M TA S M T P MAIL From: <[email protected]> RCPT To: <[email protected]> RFC 821 T C P 2) 9 R e c e i v e d M e s s a g e - I d F r o m D a t a R e p l y - T o X - P h o n e X - M a i l e r T o S u b j e c t RFC 822 X RFC 822 R e c e i v e d 3) b o d y RFC 822 NVT ASCII D ATA D 1000 M TA M TA M TA c o n t e n t D ATA M TA 1 Connecting to mailhost via ether M TA M TA S e n d m a i l M TA. t u c. n o a o. e d u m a i l h o s t h o s t D N S

336 336 TCP/IP 1 sun % host mailhost mailhost.tuc.noao.edu CNAME noao.edu noao.edu A I P D N S 28-3 I n t e r n e t 28-2 MTA MTA MTA MTA Internet MTA MTA MTA MTA 28-3 Internet 4 M TA M M TA M TA m a i l h o s t S M T P M TA I n t e r n e t M TA M TA M M TA S M T P

337 28 SMTP NVT ASCII S M T P NVT ASCII bit 8 bit I n t e r n e t S M T P M I M E M I M E NVT ASCII M TA M Host Requirements RFC 30 4 ~ SMTP M X V R F Y E X P N MX Internet D N S M X M X I n t e r n e t RFC 974 [Partridge 1986 ] M TA M X m l f a r m. c o m I n t e r n e t M X I n t e r n e t M X M TA v MTA ( ) MX SMTP

338 338 TCP/IP 1 M TA M X M X s u n s u n n o a o. e d u S L I P t c p d u m p S L I P D N S 28-4 t c p d u m p 28-4 MX 1 M TA m l f a r m. c o m M X * R R M X 0 R R R R I P 3 ~ 5 m e r c u r y. h s i. c o m S M T P T C P m e r c u r y. h s i. c o m m l f a r m. c o I n t e r n e t M X U U C P M TA M X M TA D N S RFC 974 M TA M X D N S I P M TA D N S C N A M B S D / r s t e v e n m a i l h o s t. t u c. n o a o. e d u M TA S e n d m a i l 1) Sendmail D N S m a i l h o s t. t u c. n o a o. e d u C N A M E C N A M E sun % host -t cname mailhost.tuc.noao.edu mailhost.tuc.noao.edu CNAME noao.edu 2) n o a o. e d u C N A M E D N S 3) Sendmail D N S n o a o. e d u M X sun % host -t mx noao.edu noao.edu M X n o a o. e d u 4) Sendmail D N S n o a o. e d u A I P A n o a o. e d u 3 M X R R 5) S M T P C N A M E M X n o a o. e d u M X

339 28 SMTP 339 A DNS SunOS Sendmail MX MX MX M X s u n D N S M X M X n o a o. e d u S M T P v a n g o g h. c s. b e r k e l e y. e d u s u n. t u c. n o a o. e d u 25 T C P RST SMTP M TA s u n. t u c. n o a o. e d u n o a o. e d T C P R S T S Y N t c p d u m p 28-5 SMTP 1 v a n g o g h s u n 1 I P S Y N 2 v a n g o g h S M T P s u n 2 I P R S T 4 S M T P 1 2 I P 1 host unreachable( ) 2 S M T P I P S Y N I P S Y N 1 50 M X

340 340 TCP/IP VRFY EXPN V R F Y O K E X P N S M T P S e n d m a i l S e n d m a i l S e n d m a i l Te l n e t H E L O b s d i s u n S M T P I P D N S I P I P V R F Y 550 E X P N E X P N V R F Y E X P N S M T P 28.4 SMTP I n t e r n e t I n t e r n e t S M T P A S C I I M I M E

341 28 SMTP SMTP RFC 1425 [Klensin 1993a] S M T P S M T P E S M T P E H L O H E L O 250 S M T P R F C I A N A 4 S M T P 3 S M T P Te l n e t Te l n e t 220 E H L O 250 E X P N S I Z E H E L P RFC 821 E S M T P RFC 821 S I Z E RFC 1427 [Klensin, Freed Moore 1993] MAIL FROM A S C I I I n t e r n e t E S M T P 250 S I Z E B I T M I M E RFC 1426 [Klensin 1993 a ] B O D Y MAIL FROM NVT ASCII 8 bit E H L O 8 B I T M I M E NVT ASCII M I M E M I M 8 bit X A D R X S M T P

342 342 TCP/IP 1 E S M T P H E L P S I Z E X E H L O E H L O E S M T P E H L O R S E T H E L O ASCII RFC 1522 [Moore 1993] RFC 822 A S C I I (coded word) =?c h a r s e t?e n c o d i n g?e n c o d e d - t e x t? = c h a r s e t u s - a s c i i i s o x x i s o e n c o d i n g 1) Q q u o t e d - p r i n t a b l e NVT ASCII = 8 b i t 0 x e 9 = E 9 = 20 A S C I I 2) B b i t 4 6 bit 6 b i t 64 NVT ASCII = RFC 1522

343 28 SMTP bit A S C I I 6 bit A S C I I 6 bit A S C I I 6 bit A S C I I bit S W Y g bit S = 0 x 12, W = 0 x 16, Y = 0 x 18 g = 0 x bit 3 8 bit =0x49 =0x66 =0x20 I f A S C I I Internet RFC 822 NVT ASCII RFC 1521 [Borenstein Freed 1993] M I M E I n t e r n e t M I M E S M T P A S C I I M I M E RFC 822 NVT ASCII M I M E SMTP SIZE M I M E A S C I I M I M E M I M E M I M E M TA M I M E 5 M i m e - V e r s i o n : C o n t e n t - T y p e : C o n t e n t - T r a n s f e r - E n c o d i n g :

344 344 TCP/IP 1 C o n t e n t - I D : C o n t e n t - D e s c r i p t i o n : I n t e r n e t Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=us-ascii M I M E 1. 0 A S C I I I n t e r n e t P L A I N T E X T c h a r s e t = U S - A S C I I Te x t M I M E RFC t e x t p l a i n r i c h t e x t e n r i c h e d r i c h t e x t m u l t i p a r t m i x e d p a r a l l e l d i g e s t a l t e n a t i v e m e s s a g e r f c 822 RFC 822 p a r t i a l e x t e r n a l - b o d y a p p l i c a t i o n o c t e t - s t r e a m p o s t s c r i p t P o s t S c r i p t i m a g e j p e g ISO g i f C o m p u S e r v e a u d i o b a s i c 8 bit ISDN v i d e o m p e g ISO MIME C o n t e n t - Ty p e C o n t e n t - Tr a n s f e r- E n c o d i n g RFC ) 7bit NVT ASCII 2) quoted-printable A S C I I 8 bit 1 3) base ) 8bit A S C I I 8 b i t 1 5) binary 8 bit RFC 821 MTA 5 3 N V T A S C I I 8 B I T M I M E S M T P 8 b i t R F C 1521 A S C I I t e x t q u o t e d - p r i n t a b l e i m a g e a u d i o v i d e o octet-stream application b a s e 64 RFC 821 M TA m u l t i p a r t m e s s a g e 7 b i t

345 28 SMTP 345 m u l t i p a r t 28-8 R F C m i x e d N e x t P a r t u s - a s c i i t e x t / p l a i n R F C 2 m u l t i p a r t O t h e r A c c e s s a l t e r n a t i v e 1 O t h e r A c c e s s R F C 2 F T P M I M E F T P R F C 1 RFC MIME multipart

346 346 TCP/IP 1 M I M E M I M E RFC 1521 [ R o s e ] 28.5 S M T P I n t e r n e t NVT ASCII A S C I I S M T P M I M E M I M E 7bit SMTP MTA 28.1 RFC 822 domain literal T C P S M T P T C P H E L O M A I L R C P T D ATA Q U I T 28.4 S M T P 28.5 M X

347 N F S N F S Sun RPC R P N F S N F S N F S R P C N F S I n t e r n e t U D P 29.2 Sun T C P T C P T C P T C P k e e p a l i v e A P I ( s o c k e t ) T L I A P I T C P / I P C T C P U n i x C O B O L A P I T C P P i n g Tr a c e r o u t e D N S T F T P B O O T P S N M P Te l n e t F T P S M T P RPC (Remote Procedure Call) 1) R P C s t u b 2) 3) 4) T L I A P I R P C

348 348 TCP/IP 1 A P I R P C R P C 1) 2) U D P R P C 3) RPC R P C R P C [Stevens 1990] 18 R P C Sun RPC O S F D C E R P C R P Sun RPC Sun RPC 2 RFC 1057 [Sun Microsystems 1988a] Sun RPC Sun RPCIP A P I T C P U D P T I - R P C TLI API (XID) (0) T C P U D P U D P Sun RPC R P C I P U D P U D P R P C X I D X I D X I D 29-1 RPC UDP R P C X I D R P C X I D UDP RPC (2) ( c a l l ) 0 1 R P C 2

349 ( c r e d e n t i a l ) IP 20 UDP ( v e r i f i e r ) D E S R P C (1) Sun RPC (0= ) 400 (procedure parameter) (0= ) U D P U D P U D P T C P T C P 29-2 RPC UDP T C P X I D 4 R P C R P T C P D N S R P C X I D X I D 1 0 R P C 2 R P C 0 U D P T C P R P C T C P X I D XDR: XDR (external Data Representation) R P C R P C X I D X D R RFC 1014 [Sun Microsystems 1987] X D R R P C X D R R P C X D R X I D 4 X D R 4 X D R 29.4 (XID) R P C

350 350 TCP/IP 1 R P C Sun RPC (port mapper) I n t e r n e t T C P U D P T I - R P C T C P U D P T I - R P S V R 4 Solaris 2.2 r p c b i n d U D P 111 T C P 111 R P C T C P 111 U D P 111 R P C R P C 1) PMAPPROC_SET R P C 2) PMAPPROC_UNSET R P C 3) PMAPPROC_GETPORT R P C 4) PMAPPROC_DUMP R P C R P C 1) T C P T C P 111 U D P U D 111 U D P 2) R P C T C P U D P R P C T C P U D P R P C P M A P P R O C _ S E T 3) R P C P M A P P R O C _ G E T P O RT 4) R P C 3 U D P R P C 29-1 U D P U D P R P C 29-2 U D P T C P T C P T C R P C R P r p c i n f o ( 8 ) P M A P P R O C _ D U M P NFS

351 NFS NFS mount daemon T C P 702 U D P 699 lock manager 29.5 NFS N F S F T P 27 F T P N F S N F S N F S N F S Sun RPC N F S N F R P C N F S N F S N F S N F N F S N F S R F C NFS [Sun Microsystems 1988b] [ X / O p e n 1991] Sun RPC X D R N F S [Stern 1991] N F S 3 N F S N F S N F S 1) N F S N F S N F 2) NFS T C P / I P N F S R P C N F S U D P T C P 3) NFS 2049 U D P N F S U D P ) N F S 5) NFS N F S N F S

352 352 TCP/IP 1 U n i x n f s d NFS NFS TCP/UDP IP TCP/UDP IP UDP NFS NFS 6) N F S N F S R P C N F S N F S U n i x N F S b i o d U n i x N F S N F S P C M S - D O S N F S I B M N F S N F S N F S 29-4 N F S R P C N F S , 2, NFS RPC SunOS Solaris SVR4 3 N F S N F S

353 N F S N F N F S [X/Open 1991] 9, N F S N F S (file handle) ( o p a q u e ) N F S N F N F S N F S N F S N F S 2 N F S U n i x i - n o d e i - n o d i-node U n i x m o u n t( 8 ) N F S mount (1) mountd (6) mount (2) RPC (3) RPC (4) R P C (5) RPC 29-5 Unix mount 1) 2) m o u n t d T C P

354 354 TCP/IP 1 U D P 3) m o u n t R P C T C P U D U D P sun 4) 5) m o u n t R P C T C P U D P bsdi U D P I P NFS 6) 7) m o u n t m o u n t 5 N F S 29-6 b s d i :/ u s r s u n / n f s / b s d i / u s r m o u n t m o u n t s u n N F S sun # mount -t nfs bsdi:/usr /nfs/bsdi/usr b s d i N F S / u s r / n f s / b s d i / u s r 29-6 s u n /nfs/bsdi/usr/rstevens/hello.c b s d i / u s r / r s t e v e n s / h e l l o. c NFS N F S 15 N F S N F S U n i x U n i x [Stevens 1992] 4 U n i x N F S 1) GETAT T R 2) SETAT T R

355 ) STAT F S U n i x d f 4) LOOKUP N F S N F S 5) READ ) WRITE 7) CREAT E 8) REMOVE 9) RENAME 10) LINK U n i x 11) SYMLINK 12) READLINK 13) MKDIR 14) RMDIR 15) READDIR U n i x l s N F S P R O C _ UDP TCP N F S U D P T C T C P N F S L A N WA N round-trip time WA N T C P U D P N F S T C P TCP NFS Net/2 NFS U D P T C P [Macklem 1991] T C P 1) N F S T C P 2049 N F S NFS UDP U D P 2049 U D P 2) T C P T C 2049 T C P T C P

356 356 TCP/IP 1 3) T C P k e e p a l i v e 4) T C P 29-6 b s d i / u s r s m i t h / n f s / b s d i / u s r / r s t e v e n s / n f s / b s d i / u s r / s m i t h T C P 5) T C P T C P 6) T C P k e e p a l i v e k e e p a l i v e T C P T C P N F S 29.6 NFS t c p d u m p N F S t c p d u m p R P C U D P N F S U D P R P C t c p d u m p N F S c a t ( 1 ) N F S sun % cat /nfs/bsdi/usr/rstevens/hello.c m a i n () { p r i n t f ("hello, world\n "); } 29-6 s u n N F S /nfs/bsdi/usr b s d i N F S /usr c a t s u n N F S 29-7 t c p d u m p t c p d u m p N F S X I D 1 2 X I D 0 x 7 a a 6 /nfs/bsdi/usr/rstevens/hello.c / n f s / b s d i / u s r N F S 1 G E TAT T R / u s r R P C I P U D P O K I P U D P 96 N F S 100

357 NFS 3 L O O K U P r s t e v e n s 4 O K L O O K U P r s t e v e n s 5 4 h e l l o. c L O O K U P / n f s / b s d i / u s r / r s t e v e n s / h e l l o. c L O O K U P 7 G E TAT T R 9 R E A D R P C R E A D h e l l o. c R P C o p e n 3 R P C 3 1 ~ 6 r e a d 7 ~ 10 N F S N F S sun % cd /nfs/bsdi/usr/rstevens sun % mkdir Mail t c p d u m p 29-8 NFS cd NFS mkdir

358 358 TCP/IP 1 G E TAT T R 1 ~ 4 G E TAT T R 5 ~ 6 L O O K U P 7 ~ 8 M K D I R O K t c p d u m p N F S O K N F S N F S N F S N F ( s t a t e l e s s ) N F S o p e n c l o s e L O O K U P o p e n L O O K U P N F S s u n N F S s v r 4 / u s r / s h a r e / l i b / t e r m c a p c a t NFS read t c p d u m p 1 ~ R E A D O K U n i x N F S I / O R P C ~ N F S A R P R E A D , 0.87, 1.74, 3.48, 6.96, 13.92, 20.0, 20.0, N F S

359 , 1.75, 3.5, NFS 5

360 360 TCP/IP R P C Idempotent Procedure N F S 29-9 R E A D R P C U D P R E A D R E A D N F S N N R E A D N F S R E A D W R I T E N F S R E M O V E N F S O K N F S N F S N F S G E TAT T R S TAT E S L O O K U P R E A D W R I T E R E A D L I N K R E A D D I R C R E AT E R E M O V E R E N A M E L I N K S Y M L I N K M K D I R R M D I R S E TAT T R U D P N F S N F S [Juszczak 1989] U D P N F S D N S D N S NFS 1993 N F S [Sun Microsystem 1994] V 2 V 1) V2 32 V 3 64 X D R 4 U n i x 12 U n i x 2) V2 R E A D WRITE RPC 8192 V 3

361 U D P I P ) R E A D W R I T E ) G E TAT T R 5) WRITE V 2 W R I T E W R I T E 6) V3 S TAT F S A C C E S S M K N O D U n i x R E A D D I R P L U S F S I N F O F S S TAT PAT H C O N F P O S I X. 1 C O M M I T 29.8 R P C - R P C R P C R P C X D R R P C R P C S u n N F S N F S U D P T C P 2 N F S 15 N F S N F S t c p d u m p N F S X I D t c p d u m p R P C 29.2 U n i x R P C 29.3 R P C N F S

362 362 TCP/IP N F S R E M O V E T C P U D P 29.7 N F S 2049 N F S N F S N F S T C P N N

363 30 TCP/IP 30.1 T C P / I P F i n g e r W h o i s X T C P / I P I n t e r n e t I n t e r n e 30.2 Finger F i n g e r RFC1288 [Zimmerman 1991] F i n g e r F i n g e r 1988 I n t e r n e t R F C 1135 [Reynolds 1989] [Curry 1992] F i n g e r R F C F i n g e r 79 NVT ASCII F T P S M T P U n i x finger ( 1 ) F i n g e r Te l n e t F i n g e r NVT ASCII C R L F Telnet Finger Telnet o ff i c e o ffice phone ( p a s s w o r d )

364 364 TCP/IP 1 Te l n e t F i n g e r 79 R S T 79 Finger I n t e r n e t I P [Cheswick and Bellovin 1994] I n t e r n e t 79 T C P F i n g e r U n i x F i n g e r R F C 1288 f i n g e r ( 1 ) R F C 1288 F i n g e r T C P / I P 30.3 Whois W h o i s W h o i I n t e r N I C r s. i n t e r n i c. n e t D N S I n t e r n e t n i c. d d n. m i l M I L N E T RFC954 [Harrenstein, Stahl,

365 TCP/IP and Feinler 1985] W h o i s W h o i s T C P 43 NVT ASCII W h o i s F i n g e r U n i x whois(1) Te l e n t N I C I n t e r N I C W h o i s n i c. d d n. m i l r s. i n t e r n i c. n e t n i c. d d n. m i l w h o i s -h rs.internic.net Telnet rs.internic.net whois W h o i s Te l n e t s t e v e n s 25 stevens W R S 28 N I N I C I n t e r n e t net B S M T P V R F Y F i n g e r W h o i s I n t e r n e t [Schwartz and Tsirigotis 1991] I n t e r n e t N e t f i n d Te l e n t n e t f i n d b r u n o. c s. c o l o r a d o d s. i n t e r n i c. n e t RFC1309 [We i d e r, Reynolds, and Heker 1992] O S I X. 500 I n t e r n e t F i n g e r W h o i s

366 366 TCP/IP Archie WAIS Gopher Veronica WWW F i n g e r W h o i s I n t e r n e t [Obraczka, Danzig, and Li1993] I n t e r n e t Archie F T P F T P A r c h i e I n t e r n e t F T P A r c h i e F T P F T P A r c h i e Te l n e t a r c h i d s. i n t e r n i c. n e t s e r v e r s A r c h i e WAIS A r c h i e WAIS (Wide Area Information Servers ) WA I S WA I S Te l n e t w a i s q u a k e. t h i n k. c o m Gopher G o p h e r I n t e r n e t A r c h i e WA I S F T P G o p h e r G o p h e r Te l n e t g o p h e r i s. i n t e r n i c. n e t Veronica A r c h i e F T P Ve r o n i c a ( Very Easy Rodent-Oriented Netwide Index to Computerized Archives) G o p h e r Ve r o n i c a G o p h e r G o p h e r Ve r o n i c a G o p h e r B e y o n d InterNIC: Virtual Treasures of the Internet Ve r o n i c a

367 TCP/IP WWW / W W W Te l n e t i n f o. c e r n. c h 30.5 X X (X Window System) X T C P D E C N E T X X T C P X U D P 8 bit [Nye 1992] T C P 150 U n i x X X U n i x T C P T C P U n i x 2-4 T C P I ( l o o p b a c k ) T C P I P U n i x T C P (window manager) Te l n e t F T P X X Te l n e t F T P X T C P n n 0 U n i x / t m p /. X 11 - u n i x / Xn U n i x n T C P n T C P

368 368 TCP/IP 1 A TCP B C 30-1 X X X X A B X C T C P T C P F T P Te l n e t X X T C P Xclock Xclock 1 X T C P X Xt e r m 3 2 X I P T C P 72 X [Droms and Dyksen 1990] X T C P Xscope Xs c o p e X

369 TCP/IP 30-3 A B TCP X C 30-3 x s c o p e X x s c o p e x s c o p e T C P 1 0 x s c o p e x s c o p e 6000 T C P s u n x s c o p e s v r 4 x c l o c k svr4 % DISPLAY=sun:1 xclock -digital -update 5 s u n 5 Thu Sep 9 10:32: x s c o p e - q

370 370 TCP/IP R E S O U R C E _ M A N A G E R X LBX X X X S L I P P P P X L B X 6 X F i n g e r W h o i s F i n g e r W h o i s I n t e r N I C I n t e r n e t A r c h i e WA I S G o p h e r Ve r o n i c a W W W, I n t e r n e t T C P / I P X T C P X s c o p e 30.1 W h o i s 88 A 30.2 W h o i s w h i t e h o u s e. g o v D N S D N x s c o p e X

371 A tcpdump t c p d u m p Van Jacobson Craig Leres Steven McCanne t c p d u m p promiscuous mode 2. 2 t c p d u m p t c p d u m p 4. 4 B S D B S D / 386 S u n O S U l t r i x H P - U X t c p d u m p R E A D M E t c p d u m p 10-8 Solaris 2.2 s n o o p AIX i p t r a c e A.1 BSD B S D U n i x BSD BPF (BSD Packet Filter) t c p d u m p B P F S L I P 2. 4 B P F 2. 7 B P F 1980 Mike Accetta Rick Rashid E n e t J e ffrey Mogul B S D 1983 D E C U l t r i x SunOS 4.1 STREAMS NIT B P F Steven McCanne B P F Van Jacobson [McCanne and Jacobson 1993] Sun NIT A - 1 B P F B P F A - 1 t c p d u m p R A R P 5. 4 t c p d u m p t c p d u m p r a r p d R A R P B P F C P U

372 372 TCP/IP 1 B P F t c p d u m p 1 B P F R A R P r a r p d 0 BPF A-1 BSD B P F B P F R A R P t c p d u m p t c p d u m B P F t c p d u m p % tcpdump tcp port 25 % tcpdump icmp [0]!= 8 and icmp[0]!= 0 25 T C P I C M P p i n g I C M P 6-2 t y p e U n i x t c p d u m p (1) bpf(4) B P F [McCanne and Jacobson 1993] A.2 SunOS SunOS 4.1.x S T R E A M S (pseudo-device driver) (Network Interface Ta p ) N I T [Rago 1993]

373 373 A tcpdump N I T B S D A - 2 N I T A - 1 B P F N I T t c p d u m p N I T B P F SunOS 4.1.x / d e v / n i t n i t _ i f N I T n i t _ i f t c p d u m p n i t _ b u f S T R E A M B P F R A R P A-2 SunOS n i t _ p f A - 2 R A R P t c p d u m p S u n O S t c p d u m p n i t _ p f B P F B P F t c p d u m p B P F N I T A.3 SVR4 S V R 4 DLPI (Data Link Provider Interface) O S I S V R 4 D L P I S V R S u n Solaris 2.x t c p d u m p D L P I S o l a r i s 2. x p f m o d b u f m o

374 374 TCP/IP 1 Solaris 2.x t c p d u m p S u n s n o o p t c p d u m p s n o o p SunOS 4.x e t h e r f i n d t c p d u m p vanilla SVR4 A.4 tcpdump t c p d u m p t c p d u m p 09 : 11 : m s 09 : 11 : B H H : M M : S S 6 10 ms t c p d u m p s u n B S D / 386 b s d i 10 ms 5-1 b s d i 1. 0 B S D / 386 t c p d u m p t c p d u m p 6-11 t c p d u m p t c p d u m p 4-4 t c p d u m p A t c p d u m p t c p d u m p 0 4 A t c p d u m p

375 375 A tcpdump A.5 T e l n e t F T P U n i x / e t c / p a s s w d / e t c / s h a d o w t c p d u m p t c p d u m p t c p d u m p S u n O S N I T B S D / d e v / b p f X X I D t c p d u m p A.6 T C P T C P S u nos 4.4BSD SVR4 t r p t ( 8 ) t r p t t r p s o c k C - D t c p d u m p T C P t c p d u m p

376 B U n i x U n i x [ L e ffler et al. 1989] Sun SPA R C Intel ms RFC1305 [Mills 1992] 7 10 ms R F C 1305 U n i x 10 ms 1 10 ms 10 ms U n i x 10 ms S PA R C N I T t c p d u m p A S PA R C g e t t i m e o f d a y( 2 ) g e t t i m e o f d a y B-1 SPARC ELC g e t i m e o f d a y S PARC ELC B g e t t i m e o f d a y 37 E L C 21 M I P S M I P S M I P S g e t t i m e o f d a y

377 377 B S V R 4 / Unix S V R 4 10 ms B MHz B-2 SVR4/386 gettimeofday S V R m s 0 p r i n t f 9999 S PA R C B - 1 p r i n t f S V R S PA R C 8. 5 BSD/ S PA R C 8253 g e t t i m e o f d a y BSD t c p d u m p S PA R C B S D / 386 ( s u b m i l l i s e c o n d ) S V R 4 / 386 t c p d u m p 10 ms p i n g 7 t r a c e r o u t e 8 S PA R C B S D / 386 S V R 4 / 10 L A N p i n g 7 3 ms SPARC B S D / 386 p i n g BSD/ S V R 4 10 ms t c p d u m p

378 C sock s o c k T C P U D P C s o c k J u e rgen Nickelsen s o c k e t Dave Yo s t s o c k i o s o c k Mike Muuss Terry Slattery t t c p s o c k 1) C-1 s o c k C - 1 s u n b s d i e c h o sun % sock bsdi echo a test line a test line e c h o ^ D 2) s sun % sock -s sun % sock -s ) i 1024 n w sun % sock -i -n12 -w4096 bsdi discard b s d i d i s c a r d 4) i s T C P u U D P TCP s o c k

379 379 C sock b n n c f h i a. b. c. d. p NVT ASCII U D P I a. b. c. d p T C P T C P -s - n - w -r n n -i n p n i - i s P 1 q n T C P T C r n - i s n s u v U D P T C w n - i n A B D E S O _ R E U S E A D D R T C P 2 M S L U D P S O _ B R O A D C A S T I P U D S O _ D E B U G T C P A. 6 t r p t ( 8 ) I P _ R E C V D S TA D D R

380 380 TCP/IP 1 F K U D P U D I P T C P f o r k T C P S O _ K E E PA L I V E 23 L n T C P (linger time) S O _ L I N G E R n N T C P _ N O D E L AY N a g l e O n T C P P n i s i p Q n T C P R n S O _ R C V B U F n T C P U D P U D P S n S O _ S N D B U F n U D P U D P U n n T C P 20. 8

381 D = I D 1.2 D D-1 NSFNET I D 1 27 A k p n o R 10 4 g a t e w a y n e t b C R F C M T U Solaris 2.2 M T U I P 20 T C P 3.7 U D P T C P

382 382 TCP/IP r s h T C P I A R P r s h A R P r s h a r p A R P 4.2 A R P f o o f o A R P f o o t c p d u m p f o o t e m p a r p A R P f o o f o o A R P 4.3 Host Requirement R F C A R P 20 A R P A R P A R A R P o p A R P A R P R A R P R A R P R A R A R P 5.2 R A R P R A R P R A R P I C M P s h o u l d I C M P TO S 0 I C M P TO S TO 6.4 n e t s t a t s 4800 I P S u n O S g e m i n i I C M P

383 383 D SunOS S N M P Solaris 2.2 S N M P n e t s t a t-s / ms p i n g 180 ms / ms x c 0 SLIP END 7.4 C S L I P T C P T C P I P p i n g I C M P 7.5 S PA R C E L C p i n g ms RT T 8 p i n g ms RT T p i n g 8.1 T T L 0 T T L 255 T T L t r a c e r o u t e U D P I C M P I 8 8 U D P I C M P t r a c e r o u t e t r a c e r o u t e I C M P RT T 7 p i n g I C M P p i n g RT T R 1 T T L 2 R 1 1 R 2 T T L 1 0 R 3 R 3 T T L 0 T T L 2 R 3 R 2 R 3

384 384 TCP/IP T T L 1 R 1 T T L 2 R 2 T T L 3 R 3 T T L 4 U D P T T L 1 I C M P T T L 1 T T L I C M P R 3 T T L 1 I C M P I C M T T L 5 T T L 2 T T L R 2 T T L 6 R 1 T T L 7 T T L 1 t r a c e r o u t e T T L 0 1 I C M P RT T T T L R 1 R 2 R 3 T T L I C M P T T L 255 n e t b 255 T T L b u t c h 253 T T L b u t c h n e t b T T L e n s s 142. U T. w e s t n e t. n e t U D P I C M P T T L 1 T T L I C M P U D P t r a c e r o u t e 8.7 p i n g I C M P 7-1 I D I C M P t r a c e r o u t e U D P I D I C M P I U D P I C M P 8.8 p i n g I C M P I C M P t r a c e r o u t e I C M P U D 6-9 U D P t r a c e r o u t e p i n g t r a c e r o u t e p i n g t r a c e r o u t e 8.9 Solaris U D P

385 385 D I C M P RFC 792 [Postel 1981b] N 9.2 s l i p I P s u n b s d i s u n I C M P s v r 4 s v r B S D A R P A R P 4. 2 B S D A R P 9.4 A R P 4. 2 B S D k 4. 2 B S D A R P I P A R ( E t h e r n e t m e l t d o w n ) [Manber 1990] k p n o g a t e w a y R I P 10.3 R I P U D P U D P U D P O S P F I P I P I O S P F split horizon I P U D P 11 U D P U D IEEE I P U D P

386 386 TCP/IP 1 t c p d u m p = S L I P I P 11.6 IP g e m i n i U D P U D SunOS U D P U D P WA N WA N I P I P 12 U D P 12.1 I C M P n e t s t a t - r i f c o n f i g I P 1500 M T U I P N T P 13.2

387 387 D T T L 1 9 s v r 4. t u c. n o a o. e d u i n - a d d r. a r p a D N S D N S D N S 14.4 RFC D N S 14.5 N S 14.6 InterNIC A 15 B I N D A 15.1 T F T P Host Requirements RFC A P I U D P T F T P 15.2 R F C T F T P 15.4 T F T P 512 T F T P ms / R A R P

388 388 TCP/IP 1 R A R P B O O T P I R A R P U D P I I P I P 17.2 I P 17.3 I n t e r n e t NVT ASCII D N S Sun RPC I C M P I I P 8 T C P I C M P T C P TCP U D I S N 32 bit I S N I S N 18.2 s o c k U n i x A S C I I 012 Te l n e t U n i x A S C I I F I N F I N M S L 18.5 T C P s o c k connection closed by peer. T I M E _ WA I T T I M E _ WA I T 18.6 F I N F I N 18.7

389 389 D 18.8 A R P TCP SYN A R P 18.9 s o l a r i s b s d i S Y N A C K 3 T C P F I N 4 5 F I N F I N F I N E O F T C P F I N R S T A C K R S T A C K 6 1 A C K I S N [Crowcroft et al. 1992] U D P T C P = T I M E _ WA I T 2 M S L F I N 2 M S L T I M E _ WA I T R S T T I M E _ WA I ( a s s a s s i n a t i o n ) RFC1337 [Braden 1992a] R F C T I M E _ WA I T R S F I N I P I P T C P I 19.1 N a g l e ms RT T C S L I P I P T C P S L I RT T 14.5 ms RT T 5~10 ms s u n b s d i

390 390 TCP/IP m s m s F 2 F 1 F S Y N 8193 F I N S Y N F I N 20.2 P U S H B S D / 386 T C P P U S H P U S H T C P T C P T C P (ACK compression) (ACK smashing) [Mogul 1993, ] I n t e r n e t A C K S V R 4 RTO 2D 4D 21.3 T F T P / ACK 1 ACK ACK ACK E s l i p b s d i 9600 b/s C S L I P 250 ms b s d i v a n g o g h 250 ms v a n g o g h 200 ms

391 391 D b s d i b s d i 200 ms s u n 18 ms 22.2 F I N S Y N 1 23 T C P F I N k e e p a l i v e k e e p a l i v k e e p a l i v e 23.2 k e e p a l i v e T C P S Y N / Mb/s F D D I 24.5 T C P R F C 1323 B S Y N / K a r n 24.9 T C P T C P E S TA B L I S H ) S Y N F I N 2) S Y N S Y N 3) S Y N F I 1 4) F I N

392 392 TCP/IP 1 F I N S P T T C P RT T S P T 5) F I N T / T C P U D 25 T / T C P U D P T / T C P 25.1 U D P 162 t r a p U D P 161 t r a p S N M P Table Access ms ms ms 26.2 T C P ~ R l o g i n T C P 4 R l o g i n 513 R l o g i n R l o g i n 512 R l o g i n M S L T I M E _ WA I T S Y N (domain literal) I P m a i l

393 393 D r s t e v e n [ ] H E L O M A I L R C P T D ATA Q U I T 28.3 (pipelining) [Rose ] b r a i n - d a m a g e d S M T P B I N D M X t c p d u m p U D P R P C 2049 U D P N F S R P C Te l n e t F T P R P C 29.3 X I D U D P X I D s t u b U D P X I D S V R 4 A R P s u n N F S s u n s u n A R P s u n s v r 4 A R P A R P 29.5 I / O ~ I / O

394 394 TCP/IP 1 I / O 29.6 T C P T C P T C P T C P T C P T C P N F S U D P N F S N F S 29.7 N F S N F S R P C R P C 29.8 N F S T C P 30 I P I P 4 I P 30.1 w h o i s net 88A 64 ~ whois whitehouse-dom h o s t n s l o o k u p D N S 30.3 x s c o p e x s c o p T C P 6000

395 E T C P / I P U D P I P T C P / I P T C P / I P i f c o n f i g I P T C P / I P E.1 BSD/ B S D B S D c o n f i g( 8 ) C IPFORWARDING i p f o r w a r d i n g 0 I P 1 GATEWAY I P F O RWA R D I N G 1 A R P SUBNETSARELOCAL s u b n e t s a r e l o c a l 1 I P 0

396 396 TCP/IP 1 I P E - 1 s u b n e t s a r e l o c a l E-1 subnetarelocal T C P M S S T C P M T U M S S T C P t c p _ m s s d f l t M S S IPSENDREDIRECTS i p s e n d r e d i r e c t s 1 I P I C M P 0 I C M P DIRECTED_BROADCAST 1 0 / u s r / s r c / s y s / n e t i n e t t c p r e x m t t h r e s h A C K 3 t c p _ t t l T C P T T L 60 t c p _ m s s d f l t TCP MSS 512 t c p _ k e e p i d l e k e e p a l i v e 500 ms t c p _ k e e p i n t v l k e e p a l i v e 500 ms t c p _ s e n d s p a c e T C P 4096 t c p _ r e c v s p a c e T C P 4096 u d p c k s u m 0 U D P U D P 0 U D P 0 U D P U D P 1

397 E 397 u d p _ t t l U D P T T L 30 u d p _ s e n d s p a c e U D P U D 9126 u d p _ r e c v s p a c e U D P E.2 SunOS SunOS B S D / 386 C c o n f i g( 8 ) IPFORWARDING i p _ f o r w a r d i n g 1 I P 0 I P 1 1 I P SUBNETSARELOCAL i p _ s u b n e t s a r e l o c a l 1 I P 0 I P E - 1 T C P M T U M S S T C P t c p _ d e f a u l t _ m s s M S S IPSENDREDIRECTS i p _ s e n d r e d i r e c t s 1 I P I C M P 0 I C M P DIRECTED_BROADCAST i p _ d i r b r o a d c a s t 1 0 / u s r / k v m / s y s / n e t i n e t / i n _ p r o t o. c t c p _ d e f a u l t _ m s s TCP MSS 512 t c p _ s e n d s p a c e T C P 4096

398 398 TCP/IP 1 t c p _ r e c v s p a c e T C P 4096 t c p _ k e e p l e n 4. 2 B S D k e e p a l i v e 1 t c p _ t t l T C P T T L 60 t c p _ n o d e l a c k 0 A C K 0 t c p _ k e e p i d l e k e e p a l i v e 500 ms t c p _ k e e p i n t v l k e e p a l i v e 500 ms u d p _ c k s u m 0 U D P U D P 0 U D P 0 U D P U D P 0 u d p _ t t l U D P T T L 60 u d p _ s e n d s p a c e U D P U D 9000 u d p _ r e c v s p a c e U D P E.3 SRV4 S V R 4 T C P / I P / e t c / c o n f / p a c k. d / i p / s p a c e. c 5 IPFORWARDING i p f o r w a r d i n g 0 I P 1 I P IPSENDREDIRECTS i p s e n d r e d i r e c t s 1 I P I C M P 0 I C M P t c p _ k e e p i d l e

399 E 399 E.4 Solaris 2.2 Solaris 2.2 U n i x T C P / I P n d d( 1 ) U D P 5 / d e v / i p / d e v / i c m p / d e v / a r p / d e v / u d p / d e v / t c p n d d solaris % ndd /dev/tcp tcp_mss_def 536 solaris # ndd -set /dev/ip ip_forwarding 0 1) i p _ f o r w a r d i n g 2) A R P i f c o n f i g n e t s t a t a r p 3) ms /dev/ip i p _ c k s u m _ c h o i c e I P i p _ d e b u g 0 i p _ d e f _ t t l I P T T L 255 i p _ f o r w a r d _ d i r e c t e d _ b r o a d c a s t s 1 0 i p _ f o r w a r d _ s r c _ r o u t e d 1 0

400 400 TCP/IP 1 i p _ f o r w a r d i n g I P i p _ i c m p _ r e t u r n _ d a t a _ b y t e s I C M P I P 64 i p _ i g n o r e _ d e l e t e _ t i m e I P I R E 30 i p _ i l l _ s t a t u s I P i p _ i p i f _ s t a t u s I P I P i p _ i r e _ c l e a n u p _ i n t e r v a l I P ms 3 0 i p _ i r e _ f l u s h _ i n t e r v a l I P A R P ms 2 0 i p _ i r e _ p a t h m t u _ i n t e r v a l M T U M T U ms 3 0 i p _ i r e _ r e d i r e c t _ i n t e r v a l I C M P I P ms 6 0 i p _ i r e _ s t a t u s I P i p _ l o c a l _ c k s u m 0 I P I T C P U D P I C M P I G M P 1 i p _ m r t d e b u g 1 0 i p _ p a t h _ m t u _ d i s c o v e r y 1 I P M T U 0 I P i p _ r e s p o n d _ t o _ a d d r e s s _ m a s k 0 I C M P 1 i p _ r e s p o n d _ t o _ e c h o _ b r o a d c a s t 1 I C M P 0 i p _ r e s p o n d _ t o _ t i m e s t a m p 0 I C M P 1 i p _ r e s p o n d _ t o _ t i m e s t a m p _ b r o a d c a s t 0 I C M P 1

401 E 401 i p _ r p u t _ p u l l u p s I P 0 i p _ s e n d _ r e d i r e c t s 1 I C M P 0 i p _ s e n d _ s o u r c e _ q u e n c h 1 I C M P 0 i p _ w r o f f _ e x t r a I P 32 /dev/icmp i c m p _ b s d _ c o m p a t 1 I P I I P I C M P 0 i c m p _ d e f _ t t l I C M P T T L 255 i c m p _ w r o f f _ e x t r a I P 32 /dev/arp a r p _ c a c h e _ r e p o r t A R P a r p _ c l e a n u p _ i n t e r v a l A R P A R P ms 5 I A R P i p _ i r e _ f l u s h _ i n t e r v a l a r p _ d e b u g 1 A R P 0 /dev/udp u d p _ d e f _ t t l U D P T T L 255 u d p _ d o _ c h e c k s u m 1 U D P U D P 0 U D P U D P 0 u d p _ l a r g e s t _ a n o n _ p o r t U D P 65535

402 402 TCP/IP 1 u d p _ s m a l l e s t _ a n o n _ p o r t U D P u d p _ s m a l l e s t _ n o n p r i v _ p o r t 1024 u d p _ s t a t u s U D P I P I P u d p _ t r u s t _ o p t l e n u d p _ w r o f f _ e x t r a I P 32 /dev/tcp t c p _ c l o s e _ w a i t _ i n t e r v a l 2 M S L T I M E _ WA I T ms 4 t c p _ c o n n _ g r a c e _ p e r i o d S Y N 500 ms t c p _ c o n n _ r e q _ m a x 5 t c p _ c w n d _ m a x t c p _ d e b u g 1 T C P 0 t c p _ d e f e r r e d _ a c k _ i n t e r v a l A C K 50 ms t c p _ d u p a c k _ f a s t _ r e t r a n s m i t A C K 3 t c p _ e a g e r _ l i s t e n e r s 1 T C P T C P 0 T C P S Y N 0 t c p _ i g n o r e _ p a t h _ m t u 1 M T U I C M P 0 T C P M T U t c p _ i p _ a b o r t _ c i n t e r v a l T C P ms 4 t c p _ i p _ a b o r t _ i n t e r v a l T C P ms 2 t c p _ i p _ n o t i f y _ c i n t e r v a l

403 E 403 TCP IP ms 10 t c p _ i p _ n o t i f y _ i n t e r v a l T C P I P ms 1 0 t c p _ i p _ t t l T C P T T L 255 t c p _ k e e p a l i v e _ i n t e r v a l k e e p a l i v e ms 2 t c p _ l a r g e s t _ a n o n _ p o r t T C P t c p _ m a x p s z _ m u l t i p l i e r M S S 1 t c p _ m s s _ d e f M S S 536 t c p _ m s s _ m a x M S S t c p _ m s s _ m i n M S S 1 t c p _ n a g l i m _ d e f N a g l e M S S T C P _ N O D E L AY 1 N a g l e t c p _ o l d _ u r p _ i n t e r p r e t a t i o n 1 B S D 0 R F C t c p _ r c v _ p u s h _ w a i t P U S H t c p _ r e x m i t _ i n t e r v a l _ i n i t i a l 500 ms t c p _ r e x m i t _ i n t e r v a l _ m a x ms 6 0 t c p _ r e x m i t _ i n t e r v a l _ m i n 200 ms t c p _ r w i n _ c r e d i t _ p c t 50 t c p _ s m a l l e s t _ a n o n _ p o r t

404 404 TCP/IP 1 T C P t c p _ s m a l l e s t _ n o n p r i v _ p o r t 1024 t c p _ s n d _ l o w a t _ f r a c t i o n 0 t c p _ s t a t u s T C P t c p _ s t h _ r c v _ h i w a t 0 t c p _ s t h _ r c v _ l o w a t 0 t c p _ w r o f f _ x t r a I P 32 E.5 AIX A I X n o aix % no -o udp_ttl udp_ttl = 30 a r p t _ k i l l c A R P 20 i p f o r w a r d i n g 1 I P 0 i p f r a g t t l I P 60 i p s e n d r e d i r e c t s 1 I P I C M P 0 I C M P l o o p _ c h e c k _ s u m 1 I P 0 n o n l o c s r c r o u t e 1 0 s u b n e t s a r e l o c a l 1 I P 0 I P E - 1 T C P M T U M S S T C P 536 M S S t c p _ k e e p i d l e

405 E 405 k e e p a l i v e 500 ms t c p _ k e e p i n t v l k e e p a l i v e 500 ms t c p _ r e c v s p a c e T C P t c p _ s e n d s p a c e T C P t c p _ t t l T C P T T L 60 u d p _ r e c v s p a c e U D P u d p _ s e n d s p a c e U D P U D 9216 u d p _ t t l U D P T T L 30 E.6 4.4BSD 4. 4 B S D s y s c t l 8 S N M P M I B vangogh % sysctl net.inet.ip.forwarding net.inet.ip.forwarding = 1 vangogh # sysctl -w net.inet.ip.ttl=128 n e t. i n e t. i p. f o r w a r d i n g 0 I P 1 n e t. i n e t. i p. r e d i r e c t 1 I P I C M P 0 I C M P n e t. i n e t. i p. t t l T C P U D P T T L 64 n e t. i n e t. i c m p. m a s k r e p l 0 I C M P 1 n e t. i n e t. u d p. c h e c k s u m 1 U D P U D P 0 U D P 0 U D P U D P t c p _ k e e p i d l e s u b n e t a r e l o c a l

406 F F T P F T P I n t e r n e t F T P I n t e r n e t F T P I n t e r n e t [LaQuey 1993] [Krol 1992] I n t e r n e t A r c h i e F T P d i r RFC R F C F T P R F C R F C R F C R F C R F BSD Net/ BSD Net/2 T C P / I P Te l n e t F T P f t p. u u. n e t s y s t e m / u n i x / b s d - s o u r c e SLIP 2.4 S L I P f t p. e e. l b l. g o v c s l i p S L I P 2. 5 icmpaddrmask 6.3 icmptime 6.4 ping 7 B S D p i n g f t p. u u. n e t

407 407 F s y s t e m / u n i x / b s d - s o u r c e s / s b i n / p i n g p i n traceroute 8 t r a c e r o u t e f t p. e e. l b l. g o v g r e g o r i o. s t a n f o r d. e d u g w - d i s c o v e r y / n o r d m a r k - r d i s c. t a r S u n gated g a t e d g a t e d. c o r n e l l. e d u traceroute.pmtu 11.7 IP 13 SunOS 4.x U l t r i x I P g r e g o r i o. s t a n f o r d. e d u v m t p - i p U n i x I P BIND 14 B I N D n a m e d f t p. u u. n e t n e t w o r k i n g / i p / d n s / b i n d / b i n d t a r. z 4. 9 g a t e k e e p e r. d e c. c o m p u b / B S D / b i n d / 4. 9 host 14 h o s t n i k h e f h. n i k h e f. n l h o s t. t a r. z dig doc d i g d o c i s i. e d u d i g t a r. Z d o c t a r. Z BOOTP 26 Unix BOOTP l a n c a s t e r. a n d r e w. c m u. e d u p u b TCP 24 T C P PAW S BSD Net/2

408 408 TCP/IP 1 u x c. c s o. u i u c. e d u p u b / t c p l w. s h a r. z ISODE SNMP S N M P ISODE 8.0 f t p. u u. n e t n e t w o r k i n g / o s i / i s o d e MIME 28.4 M e t a M a i l M I M E t h u m p e r. b e l l c o r e. c o m p u b / n s b M I M E Sun RPC 29.2 RPC 4.0 A P I f t p. u u. n e t s y s t e m s / s u n / s e x t a p e / r p c 4. 0 T I - R P C TLI API f t p. u u. n e t n e t w o r k i n g / r p c Sun NFS 29 N F S BSD Net/2 tcpdump A t c p d u m p f t p. e e. l b l. g o v t c p d u m p t a r. z BSD A.1 B S D t c p d u m p sock C ttcp t t c p T C P U D P F T P f t p. s g i. c o m s g i / s r c / t t c p f t p. u u. n e t p u b l i s h e d / b o o k s / s t e v e n s. t c p i p i v 1. t a r. z

409 R F C I n t e r n e t F T P Albitz, P., and Liu, C DNS and BIND. O Reilly & Associates, Sebastopol, Calif. A l e xa n d e r, S., and Droms, R DHCP Operations and BOOTP Vendor Extensions, RFC1533, 30 pages(oct.). Almquist, P Type of Service in the Internet Protocol Suite, RFC1349, 28 pages (July). I P Almquist, P., ed Requirements for IP Routers, Internet Draft (Mar. ). RFC 1009[Braden and Postel 1987] R F C R F C 1 I n t e r n e t F T P j e s s i c a. s t a n f o r d. e d u r r e q R F C Bellovin, S. M Private Communication. B h i de, A., Elnozahy, E. N., and Morgan, S. P A Highly Available Network File Server, P roceeding of the 1991 Winter USENIX Co n f e re n c e, pp , Dallas, Te x. A R P 4. 7 B o r enstein, N., and Freed, N MIME (Multipurpose Internet Mail Extensions) Part One: Mechanisms for Specifying and Describing the Format of Internet Message Bodies, RFC 1521, 81 pages (Sept.). R F C RFC 1341 R F C H RFC 1341 Borman, D. A., ed Telnet Linemode Option, RFC 1184, 23 pages (Oct.). B o r man, D. A IP Bandwidth Limits, Message-ID A A b e r s e r k l y. c r a y. c o m >, Usenet, comp.protocols.tcp-ip Newsgroup (Jan.) T C P B o r ma n, D. A TCP/IP Performance at Cray Research, P roceeding of the Tw e n t y - t h i rd Internet Engineering Task Forc e, pp (Mar.), San Diego Supercomputer Center, San Diego, Calif. Borman, D. A., ed. 1993a. Telnet Environment Option, RFC 1408, 7 pages (Jan.). Te l n e t B o r ma n, D. A. 1993b. A Practical Perspective on Host Networking, i n Internet System Handbook, eds. D. C. Lynch and M. T. Rose, pp Addison-We s l e y, Reading, Mass. Host Requirements R F C

410 410 TCP/IP 1 B r a den, R. T., ed. 1989a. Requirements for Internet Hosts Communication Layers, R F C 1122, 116 pages (Oct.). R F C I P T C P U D P B r a den, R. T., ed. 1989b. Requirements for Internet Hosts Application and Support, R F C 1123, 98 pages (Oct.). R F C Te l n e t F T P T F T P S M T P D N S B r a den, R. T. 1989c. Perspective on the Host Requirements RFCs, RFC 1127, 20 pages ( O c t. ). R F C I E T F B r a den, R. T. 1992a. T I M E - WAIT Assassination Hazards in TCP, RFC1337, 11 pages (May). T I M E _ WA I T R S T B r a den, R. T. 1993b. Extending TCP for Tr a n s a c t i o n s C o n c e p t s, RFC 1379, 38 pages ( N o v. ). T / T C P B r a den, R. T. 1992c. Extending TCP for Tr a n s a c t i o n s Functional Specification, I n t e r n e t Draft, 32 pages (Dec.). T / T C P B r a den, R. T., Borman, D. A., and Partridge, C Computing the Internet Checksum, RFC 1071, 24 pages (Sept.). I P I C M P I G M P U D P T C P B r a den, R. T., and Postel, J. B Requirements for Internet Gateways, RFC1009, 55 pages (June). R F C R F C [Almquist 1993] C a c eres, R., Danzig, P. B., Jamin, S., and Mitzel, D. J Characteristics of Wi d e - A r e a TCP/IP Conversations, Computer Communication Review, vol. 21, no. 4, pp ( S e p t. ). Callon, R TCP and UDP with Bigger Addresses (TUBA), A Simple Proposal for Internet Addressing and Routing, RFC 1347, 9 pages (June). C a s e, J. D., Fedor, M. S., Schoffstall, M. L., and Davin, C Simple Network Management ( S N M P ), RFC 1157, 36 pages (May). S N M P C a s e, J. D., McCloghrie, K., Rose, M. T., and Wa l d b u s s e r, S An Introduction to Ve r s i o n 2 of the Internet-Standard Network Management Framework, RFC 1441, 13 pages (Apr. ). S N M P v 2 11 S N M P v 2 R F C C a s e, J. D., and Partridge, C Case Diagrams: A First Step to Diagrammed Management Information Bases, Computer Communication Review, vol. 19, no. 1, pp (Jan.). S N M P C a s ne r, S., and Deering, S. E First IETF Internet Audiocast, C o m p u t e r Communication Review, vol. 22, no. 3, pp (July).

411 411 I n t e r n e t I E T F P o s t S c r i p t F T P v e n e r a. i s i. e d u p u b / i e t f - a u t o c a s t - a r t i c l e. p s m b o n e / f a q. t x t I n t e r n e t M B O N E C h e riton, D. P VMTP: Versatile Message Transaction Protocol, RFC 1045, 123 pages ( F e b. ). C h e swick, W. R., and Bellovin, S. M F i rewalls and Internet Security: Repelling the Wi l y H a c k e r. Addison-We s l e y, Reading, Mass. C l a rk, D. D Window and Acknowledgement Strategy in TCP, RFC 813, 22 pages ( J u l y ). R F C C l a rk, D. D The Design Philosophy of the DARPA Internet Protocols, C o m p u t e r Communication Review, vol. 18, no. 4, pp (Aug.). I n t e r n e t C o me r, D. E., and Stevens, D. L I n t e r n e t w o r k i n g w i t h TCP/IP: Vol. III: C l i e n t - S e rv e r P rogramming and Applications, BSD Socket Ve r s i o n. Prentice-Hall, Englewood Cliffs, N.J. C o o p e r, A. W., and Postel, J. B The US Doman, RFC 1480, 47 pages (June). D N S. u s C r o ck e r, D. H Standard for the Format of ARPA Internet Text Messages, RFC 822, 47 pages ( A u g. ). S M T P C r o ck e r, D. H Evolving the System, in Internet System Handbook, eds. D. C. Ly n c h and M. T. Rose, pp Addison-We s l e y, Reading, Mass. A R PA N E T I n t e r n e t I n t e r n e t Croft, W., and Gilmore, J Bootstrap Protocol (BOOTP), RFC 951, 12 pages (Sept.). Crowcroft, J., Wakeman, I., Wang, Z., and Sirovica, D Is Layering Harmful?, I E E E Network, vol. 6, no. 1, pp (Jan.) C u r ry, D. A U N LX System Security: A Guide for Users and System Administrators. A d d i s o n - We s l e y, Reading, Mass. U n i x 4 5 D a l ton, C., Watson, G., Banks, D., Calamvokis, C., Edwards, A., and Lumley, J A f t e r- b u r n e r, IEEE Network, vol. 7, no. 4, pp (July). T C P D a n zig, P. B., Obraczka, K., and Kumar, A An Analysis of Wide-Area Name Server Tr a ff i c, Computer Communication Review, vol. 22, no. 4, pp (Oct.). 24

412 412 TCP/IP 1 D N S 20 WA N P o s t S c r i p t F T P c a l d e r a. u s c. e d u p u b / d a n z i g / d n s. p s. z Deering, S. E Host Extensions for IP Multicasting, RFC 1112, 17 pages (Aug.). I P I G M P Deering, S. E., ed ICMP Router Discovery Messages, RFC 1256, 19 pages (Sept.). D e e ring, S. E., and Cheriton, D. P Multicast Routing in Datagram Internetworks and Extended LANs, ACM Transactions on Computer Systems, vol. 8, no. 2, pp (May). Dixon, T Comparison of Proposals for Next Version of IP, RFC 1454, 15 pages (May). S I P, PIP T U B A Droms, R Dynamic Host Configuration Protocol, RFC 1541, 39 pages (Oct.). D r oms, R., and Dyksen, W. R Performance Measurements of the X Window System C o m m u n i c a t ion Protocol, S o ft w a re Practice & Experience, vol. 20, pp (Oct.). X T C P F e d or, M. S G ATED: A Multi-routing Protocol Daemon for Unix, P roceeding of the 1988 Summer USENIX Confere n c e, pp , San Francisco, Calif. Finlayson, R Bootstrap Loading using TFTP, RFC 906, 4 pages (June). F i n l ayson, R., Mann, T., Mogul, J. C., and Theimer, M A Reverse Address Resolution P r o t o c o l, RFC 903, 4 pages (June). Floyd, S Private Communication. F o r d, P. S., Rekhter, Y., and Braun, H-W Improving the Routing and Addressing of IP, IEEE Network, vol. 7, no. 3, pp (May). C I D R F u l l er, V., Li, T., Yu, J.Y., and Varadhan, K Classless Inter-Domain Routing (CIDR): An Address Assignment and Aggregation Strategy, RFC 1519, 24 pages (Sept.). C I D R G e r ich, E Guidelines for Management of IP Address Space, RFC 1466, 10 pages ( M a y ). I P B C G u r witz, R., and Hinden, R I P Local Area Network Addressing Issues, IEN 212, 11 pages (Sept.) I P H a r renstein, K., Stahl, M. K., and Feinler, E. J N I C N A M E / W H O I S, RFC 954, 4 pages ( O C T. ). Hedrick, C. L. 1988a. Routing Information Protocol, RFC 1058, 33 pages (June). Hedrick, C. L. 1988b. Telnet Terminal Speed Option, RFC 1079, 3 pages (Dec.). H e d rick, C. L., and Borman, D. A Telnet Remote Flow Control Option, RFC 1372, 6 pages (Oct.).

413 413 H o r nig, C Standard for the Transmission of IP Datagrams over Ethernet Networks, RFC 894, 3 pages (Apr. ). H u i tema, C IAB Recommendation for an Intermediate Strategy to Address the Issue of S c a l i n g, RFC 1481, 2 pages (July). C I D R I A B J a c obson, V Congrestion Avoidance and Control, Computer Communication Review, vol. 18, no. 4, pp (Aug.). T C P P o s t S c r i p t F T P f t p. e e. l b l. g o v c o n g a v o i d. p s. z J a c obson, V. 1990a. Compressing TCP/IP Headers for Low-Speed Serial Links, RFC , 43 pages (Feb.). C S L I P, T C P I P S L I P J a c obson, V. 199b. Modified TCP Congestion Avoidance Algorithm, April 30, 1990, end2end-interest mailing list (Apr. ). J a c obson, V. 1990c. Berkeley TCP Evolution from 4.3-Tahoe to 4.3-Reno, P roceeding of the Eighteenth Internet Engineering Task Forc e, p. 365 (Sept.), University of British Columbia, Va n c o u v e r, B.C. J a c obson, V., and Braden, R. T TCP Extensions for Long-Delay Paths, RFC 1072, 16 pages (Oct.). T C P RFC 1323 J a c obson, V. Braden, R. T., and Borman, D. A TCP Extensions for High Performance, RFC 1323, 37 pages (May). PAW S J a c obson, V., Braden, R. T., and Zhang, L TCP Extensions for High-Speed Paths, R F C 1185, 21 pages (Oct.). R F C RFC 1323 T C P J u s zczak, C Improving the Performance and Correctness of an NFS Server, P roceedings of the 1989 Winter USENIX Confere n c e, pp , San Diego, Calif. N F S K a n t o r, B BSD Rlogin, RFC 1282, 5 pages (Dec.). R l o g i n K a r n, P., and Partridge, C Improving Round-Trip Time Estimates in Reliable Tr a n s p o r t P r o t o c o l s, Computer Communication Review, vol. 17, no. 5, pp. 2-7 (Aug.). K a r n P o s t S c r i p t F T P s i c s. s e p u b / c r a i g / k a r n - p a r t r i d g e. p s K a t z, D Proposed Standard for the Transmission of IP Datagrams Over FDDI N e t w o r k s, RFC 1188, 11 pages (Oct.).

414 414 TCP/IP 1 F D D I I P A R P K e n t, C. A., and Mogul, J. C Fragmentation Considered Harmful, C o m p u t e r Communication Review, vol. 17, no. 5, pp (Aug.). K e n t, S. T U.S. Department of Defense Security Options for the Internet Protocol, RFC 1108, 17 pages (Nov. ). K l e inrock, L The Latency / Bandwidth Tr a d e o ff in Gigabit Networks, I E E E C o m m u n i c a t i o n s M a g a z i n e, vol. 30, no. 4, pp (Apr. ). K l e nsin, J., Freed, N., and Moore, K SMTP Service Extension for Message Size D e c l a r a t i o n, RFC 1427, 8 pages (Feb.). K l e nsin, J., Freed, N., Rose, M. T., Stefferud, E. A., and Crocker, D. 1993a. SMTP Service E x t e n s i o n s, RFC 1425, 10 pages (Feb.). K l e nsin, J., Freed, N., Rose, M. T., Stefferud, E. A., and Crocker, D. 1993b. SMTP Service Extension for 8bit-MIME Tr a n s p o r t, RFC 1426, 6 pages (Feb.). Krol, E The Whole Internet. O Reilly & Associates, Sebastopol, Calif. I n t e r n e t L a Qu e y, T The Internet Companion: A Beginner s Guide to Global Networking. Addison- We s l e y, Reading, Mass. I n t e r n e t L e ff le r, S. J., and Karels, M. J Trailer Encapsulations, RFC 893, 3 pages (Apr. ). L e ff le r, S. J., McKusick, M. K., Karels, M. J., and Quarterman, J. S The Design and Implementation of the 4.3BSD UNIX Operating System. Addison-We s l e y, Mass. 4.3BSD Unix Ta h o e 4. 3 B S D L o u gheed, K., and Rekhter, Y A Border Gateway Protocol 3 (BGP-3), RFC 1267, 35 pages (Oct.). Ly n ch, D. C Historical Perspective, in Internet System Handbook, eds. D. C. Ly n c h and M. T. Rose, pp Addison-We s l e y, Reading, Mass. I n t e r n e t A R PA N E T M a cklem, R Lessons Learned Tuning the 4.3BSD Reno Implementation of the NFS P r o t o c o l, P roceedings of the 1991 Winter USENIX Confere n c e, pp , Dallas, Te x. T C P U D P N F S M a l kin, G. S. 1993a. RIP Version 2: Carrying Additional Information. RFC 1388, 7 pages ( J a n. ). Malkin, G. S. 1993b. Traceroute Using an IP Option, RFC 1393, 7 pages (Jan.). t r a c e r o u t e I C M P M a l lo r y, T., and Kullberg, A Incremental Updating of the Internet Checksum, R F C 1141, 2 pages (Jan.). I n t e r n e t M a nb e r, U Chain Reactions in Networks, IEEE Computer, vol. 23, no. 10, pp ( O c t. ).

415 M c Canne, S., and Jacobson, V The BSD Packet Filter: A New Architecture for User- Level Packet Capture, P roceeding of the 1993 Winter USENIX Confere n c e. Pp , San Diego, Calif. B S D B P F S u n N I T P o s t S c r i p t F T P f t p. e e. l b l. g o v p a p e r s / b p f - u s e n i x 93. p s. Z M c Cloghrie, K., and Rose, M. T Management Information Base for Network Management of TCP/IP-based Internets: MIB-II, RFC 1213 (Mar. ). M c Gr e g o r, G PPP Internet Protocol Control Protocol (IPCP), RFC 1332, 12 pages ( M a y ). T C P / I P P P P N C P M i l ls, D. L Network Time Protocol (Version 3): Specification, Implementation, and A n a l y s i s, RFC 1305, 113 pages (Mar. ). M o ckapetris, P. V. 1987a. Domain Names: Concepts and Facilities, RFC 1034, 55 pages ( N o v. ). D N S M o ckapetris, P. V. 1987b. Domain Names: Implementation and Specification, RFC 1035, 55 pages (Nov. ). D N S M o gul, J. C E fficient Use of Workstations for Passive Monitoring of Local Area N e t w o r k s, Computer Communication Review, vol. 20, no. 4, pp (Sept.). M o gul, J. C Holy Tu r b o c h a rger Batman, (evil cheating), NFS async writes, M e s s a g e - ID 1992Mar PA.dec.com, Usenet, comp.protocols.nfs Newsgroup (Mar. ). N F S 40 I n t e r n e t M o gul, J. C IP Network Performance, in Internet System Handbook, eds. D. C. Ly n c h and M. T. Rose, pp Addison-We s l e y, Reading, Mass. T C P / I P Mogul, J. C., and Deering, S. E Path MTU Discovery, RFC 1191, 19 pages (Apr. ). M o gul, J. C., and Postel, J. B Internet Standard Subnetting Procedure, RFC 950, 18 pages (Aug.). M o ore, K MIME (Multipurpose Internet Mail Extensions) Part Two: Message Header Extensions for Non-ASCII Te x t, RFC 1522, 10 pages (Sept.). 7 bit ASCII RFC 822 A S C I I M o y, J OSPF Version 2, RFC 1247, 189 pages (July). Nagle, J Congestion Control in IP/TCP Internetworks, RFC 896, 9 pages(jan.). N a g l e N y e, A., ed The X Window System, Volume 0: X Protocol Reference Manual, Third

416 416 TCP/IP 1 E d i t i o n. O Reilly & Associates, Sebastopol, Calif. O b r acezka, K., Danzig, P. B., and Li, S Internet Resource Discovery Services, I E E E C o m p u t e r, vol. 26, no. 9, pp (Sept.). I n t e r n e t A l e x A r c h i e G o p h e r I n d i e K n o w b o t N e t f i n d P r o s p e r o WA I S W W W X. 500 P o s t S c r i p t FTP c a l d e r a. u s c. e d u / p u b / k o b r a c z k / i e e e c o m p u t e r. p s. z P a p adopoulos, C., and Parulkar, G. M Experimental Evaluation of SunOS IPC and TCP/IP Protocol Implementation, IEEE/ACM Transactions on Networking, vol. 1, no. 2, pp (Apr. ). Partridge, C Mail Routing and the Domain System, RFC 974, 7 pages (Jan.). D N S M X Partridge, C Gigabit Networking. Addison-We s l e y, Reading, Mass. 1 Gb/s P a r t ridge, C., and Pink, S A Faster UDP. IEEE/ACM Transactions on Networking, Vo l. 1, no. 4, pp (Aug.). U D P 30 % P a x son, V Empirically-Derived Analytic Models of Wide-Area TCP Connections: Extended Report, LBL-34086, Lawrence Berkeley Laboratory and EECS Division, University of California, Berkeley (June) T C P P o s t S c r i p t F T P f t p. e e. l b l. g o v W A N - T C P - m o d e l s. 1. p s. Z W A N - T C P - m o d e l s. 2. p s. Z Perlman, R I n t e rconnections: Bridges and Routers. Addison-We s l e y, Reading, Mass. P l u m m e r, D. C An Ethernet Address Resolution Protocol, RFC 826, 10 pages (Nov. ). Postel, J. B User Datagram Protocol, RFC 768, 3 pages (Aug.). Postel, J. B., ed. 1981a. Internet Protocol, RFC 791, 45 pages (Sept.). Postel, J. B. 1981b. Internet Control Message Protocol, RFC 792, 21 pages (Sept.). Postel, J. B., ed. 1981c. Transmission Control Protocol, RFC 793, 85 pages (Sept.). Postel, J. B Simple Mail Transfer Protocol, RFC 821, 68 pages (Aug.). Postel, J. B TCP and IP Bake Off, RFC 1025, 6 pages (Sept.). T C P / I P Postel, J. B., ed Internet Official Protocol Standards, RFC 1600, 36 pages (Mar. ). I n t e r n e t R F C R F C P o s tel, J. B., and Reynolds, J. K. 1983a. Telnet Protocol Specification, RFC 854, 15 pages ( M a y ).

417 417 Te l n e t R F C Te l n e t P o s tel, J. B., and Reynolds, J. K. 1983b. Telnet Binary Tr a n s m i s s i o n, RFC 856, 4 pages ( M a y ). Postel, J. B., and Reynolds, J. K. 1983c. Telnet Echo Option, RFC 857, 5 pages (May). P o s tel, J. B., and Reynolds, J. K. 1983d. Telnet Suppress Go Ahead Option, RFC 858, 3 pages (May). Postel, J. B., and Reynolds, J. K. 1983e. Telnet Status Option, RFC 859, 3 pages (May). P o s tel, J. B., and Reynolds, J. K. 1983f. Telnet Timing Mark Option, RFC 860, 4 pages ( M a y ). P o s tel, J. B., and Reynolds, J. K File Transfer Protocol (FTP), RFC 959, 69 pages ( O c t. ). P o s tel, J. B., and Reynolds, J. K Standard for the Transmission of IP Datagrams over IEEE 802 Networks, RFC 1042, 15 pages (Apr. ). IEEE 802 I P A R P P u s ateri, T IP Multicast Over Token-Ring Local Area Networks, RFC 1469, 4 pages ( J u n e ). Rago, S. A UNIX System V Network Pro g r a m m i n g. Addison-We s l e y, Reading, Mass. T L I R e k ht e r, Y. and Gross, P Application of the Border Gateway Protocol in the Internet, RFC 1268, 13 pages (Oct.). R e k ht e r, Y., and Li, T An Architecture for IP Address Allocation with CIDR, R F C 1518, 27 pages (Sept.). Reynolds, J. K The Helminthiasis of the Internet, RFC 1135, 33 pages (Dec.) I n t e r n e t Reynolds, J. K., and Postel, J. B Assigned Numbers, RFC 1340, 138 pages (July). I n t e r n e t R F C R F C R o mk e y, J. L A Nonstandard for Transmission of IP Datagrams Over Serial Lines: S L I P, RFC 1055, 6 pages (June). R o s e, M. T The Open Book: A Practical Perspective on OSI. Prentice-Hall, Englewood C l i ffs, N.J. O S I 8 A S N. 1 B E R R o s e, M. T The Internet Message: Closing the Book with Electronic Mail. P r e n t i c e - H a l l, Englewood Cliffs, N.J. I n t e r n e t M I M E R o s e, M. T The Simple Book: An Introduction to Internet Management, Second Edition. Prentice-Hall, Englewood Cliffs, N.J. S N M P v 2 1 S N M P v 1 R o s e, M. T., and McCloghrie, K Structure and Identification of Management

418 418 TCP/IP 1 Information for TCP/IP-based Internets, RFC 1155, 22 pages (May). S N M P v 1 S M I R o s en b e rg, W., Kenney, D., and Fisher, G U n d e r s t a n d i n g D C E. O Reilly & Associates, Sebastopol, Calif. O S F R o u th i e r, S. A Implementation Experience for SNMPv2, The Simple Ti m e s, vol. 2, no. 4, pp. 1-4 (July-Aug.). S N M P v 1 S N M P v 2 h e l p s t - s u b s c r i p t i o n s i m p l e - t i m e s. o r g S c h ry v e r, V. J Info on High Speed Transport Protocols Requested, M e s s a g e - I D [email protected], Usenet, comp.protocols.tcp-ip Newsgroup (May). F D D I T C P S c h wartz, M. F., and Tsirigotis, P. G Experience with a Semantically Cognizant Internet White Pages Directory To o l, Journal of Internetworking Research and Experience, vol. 2, no. 1, pp (Mar. ). F T P f t p. c s. c o l o r a d o. e d u p u b / c s / t e c h r e p o r t s / s c h w a r t z / PostScript/ White.Pages.ps.Z Simpson, W. A The Point-to-Point Protocol (PPP), RFC 1548, 53 pages (Dec.). P P P Sollins, K. R The TFTP Protocol (Revision 2), RFC 1350, 11 pages (July). S t a l lings, W Handbook of Computer-Communications Standards, Vo l u m e 2: Local Network S t a n d a rd s. Macmillan, New Yo r k. IEEE 802 S t a l lings, W S N M P, SNMPv2, and CMIP: The Practical Guide to Network-Management S t a n d a rd s. Addison-We s l e y, Reading, Mass. S N M P v 1 S N M P v 2 Stern, H Managing NFS and NIS. O Reilly & Associates, Sebastopol, Calif. N F S Stevens, W. R UNIX Network Pro g r a m m i n g. Prentice-Hall, Englewood Cliffs, N.J. U n i x T L I S t e v ens, W. R Advanced Programming in the UNIX Enviro n m e n t. Addison-We s l e y, Reading, M a s s. U n i x Sun Microsystems XDR: External Data Representation Standard, RFC 1014, 20 pages ( J u n e ). Sun Microsystems. 1988a. RFC: Remote Procedure Call, Protocol Specification, Version 2, RFC 1057, 25 pages (June). Sun Microsystems. 1988b. NFS: Network File System Protocol Specification, RFC 1094, 27 pages

419 419 ( M a r. ). 2 Sun NFS Sun Microsystems N F S: Network File System Version 3 Protocol Specification. Sun Microsystems, Mountain Vi e w, Calif. P o s t S c r i p t F T P f t p. u u. n e t n e t w o r k i n g / i p / n f s / N F S 3. s p e c. p s. Z Ta n enbaum, A. S Computer Networks, Second Edition. Prentice-Hall, Englewood Cliff s, N. J. Topolcic, C Status of CIDR Deployment in the Internet, RFC 1467, 9 pages (Aug.). Tsuchiya, P. F On the Assignment of Subnet Numbers, RFC 1219, 13 pages (Apr. ). I D I D Ullmann, R TP/IX: The Next Internet, RFC 1475, 35 pages (June). I n t e r n e t VanBokkelen, J Telnet Te r m i n a l - Type Option, RFC 1091, 7 pages (Feb.). Waitzman, D Telnet Window Size Option, RFC 1073, 4 pages (Oct.). Wa i tzman, D., Partridge, C., and Deering, S. E Distance Vector Multicast Routing P r o t o c o l, RFC 1075, 24 pages (Nov. ). Wa rnock, R. P Need Help Selecting Ethernet Cards for Very High Performance Throughput Rates, Message-ID< [email protected]> Usenet, comp.protocols.tcp-ip Newsgroup (Sept.) T C P We i de r, C., Reynolds, J. K., and Heker, S Technical Overview of Directory Services Using the X.500 Protocol, RFC 1309, 16 pages (Mar. ). Wi me r, W Clarifications and Extensions for the Bootstrap Protocol, RFC 1542, 23 pages (Oct.). X/Open P rotocols for X/Open Internetworking: X N F S. X/Open, Reading, Berkshire, U.K. Sun RPC X D R N F S N F S N F S X/ O p e n XO / C A E / 91 / 030 Zimmerman, D. P Finger User Information Protocol, RFC 1288, 12 pages (Dec.)

420 ACK (ACKnowledgment) TCP API (Application Programming Interface) ARP (Address Resolution Protocol) A R PA N E T (Defense Advanced Research Project Agency NETwork) ( ) AS (Autonomous System) ASCII (American Standard Code for Information Interchange) ASN.1 (Abstract Syntax Notation One) 1 BER (Basic Encoding Rule) BGP (Border Gateway Protocol) BIND (Berkeley Internet Name Domain) I n t e r n e t BOOTP (BOOTstrap Protocol) BPF (BSD Packet Filter) BSD CIDR (Classless InterDomain Routing) CIX (Commercial Internet Exchange) CLNP (ConnectionLess Network Protocol) CRC (Cyclic Redundancy Check) CSLIP (Compressed SLIP) S L I P CSMA (Carrier Sense Multiple Access) DCE (Data Circuit-terminating Equipment) DDN (Defense Data Network) DF (Don t Fragment) IP DHCP (Dynamic Host Configuration Protocol) DLPI (Data Link Provider Interface) DNS (Domain Name System) DSAP (Destination Service Access Point) DSLAM (DSL Access Multiplexer) DSSS (Direct Sequence Spread Spectrum) DTS (Distributed Time Service) DVMRP (Distance Vector Multicast Routing Protocol) EBONE (European IP BackbONE) I P EOL (End of Option List) EGP (External Gateway Protocol) EIA (Electronic Industries Association)

421 421 FCS (Frame Check Sequence) FDDI (Fiber Distributed Data Interface) FIFO (First In, First Out) FIN (FINish) TCP FQDN (Full Qualified Domain Name) FTP (File Transfer Protocol) HDLC (High-level Data Link Control) HELLO IAB (Internet Architecture Board) Internet IANA (Internet Assigned Numbers Authority) Internet ICMP (Internet Control Message Protocol) Internet IDRP (InterDomain Routing Protocol) IEEE (Institute of Electrical and Electronics Engineering) IEN (Internet Experiment Notes) IESG (Internet Engineering Steering Group) Internet IETF (Internet Engineering Task Force) Internet IGMP (Internet Group Management Protocol) Internet IGP (Interior Gateway Protocol) IMAP (Internet Message Access Protocol) Internet IP (Internet Protocol) I RTF (Internet Research Task Force) Internet IS-IS (Intermediate System to Intermediate System Protocol) ISN (Initial Sequence Number) ISO (International Organization for Standardization) ISOC (Internet SOCiety) Internet LAN (Local Area Network) LBX (Low Bandwidth X) X LCP (Link Control Protocol) LFN (Long Fat Net) LIFO (Last In, First Out) LLC (Logical Link Control) LSRR (Loose Source and Record Route) MBONE (Multicast Backbone On the InterNEt) Internet MIB (Management Information Base) MILNET (MILitary NETwork) MIME (Multipurpose Internet Mail Extensions) I n t e r n e t MSL (Maximum Segment Lifetime) MSS (Maximum Segment Size) M TA (Message Transfer Agent)

422 422 TCP/IP 1 MTU (Maximum Transmission Unit) NCP (Network Control Protocol) NFS (Network File System) NIC (Network Information Center) NIT (Network Interface Tap) S u n NNTP (Network News Transfer Protocol) NOAO (National Optical Astronomy Observatories) NOP (No Operation) NSFNET (National Science Foundation NETwork) NSI (NASA Science Internet) I n t e r n e t NTP (Network Time Protocol) NVT (Network Virtual Terminal) OSF (Open Software Foudation) OSI (Open Systems Interconnection) OSPF (Open Shortest Path First) PAWS (Protection Against Wrapped Sequence number) PDU (Protocol Data Unit) POSIX (Portable Operating System Interface) PPP (Point-to-Point Protocol) PSH (PuSH) TCP RARP (Reverse Address Resolution Protocol) RFC (Request For Comments) Internet RIP (Routing Information Protocol) RPC (Remote Procedure Call) RR (Resource Record) RST (ReSeT) TCP RTO (Retransmission Time Out) RTT (Round-Trip Time) SACK (Selective ACKnowledgment) SLIP (Serial Line Internet Protocol) I n t e r n e t SMI (Structure of Management Information) SMTP (Simple Mail Transfer Protocol) SNMP (Simple Network Management Protocol) SSAP (Source Service Access Point) SSRR (Strict Source and Record Route) SWS (Silly Window Syndrome) SYN (SYNchronous) TCP TCP (Transmission Control Protocol) TFTP (Trivial File Transfer Protocol)

423 423 TLI (Transport Layer Interface) TTL (Ti m e - To-Live) TUBA (TCP and UDP with Bigger Addresses) T C P U D P Telnet UA (User Agent) UDP (User Datagram Protocol) URG (URGent) TCP UTC (Coordinated Universal Time) UUCP (Unix-to-Unix CoPy) Unix U n i x WAN (Wide Area Network) WWW (World Wide Web) XDR (external Data Representation) XID (transaction ID) XTI (X/Open Transport Layer Interface) X/ O p e n