r4.dvi

11 4 2010.5.11 1 1.1 :???? ( : ) ( 1)? 1:? Google Web www.museuhistoriconacional.com.br ping % /sbin/ping www.museuhistoriconacional.com.br PING museuhistoriconacional.com.br (200.198.87.5): 56 data bytes 64 bytes from 200.198.87.5: icmp_seq=0 ttl=228 time=334.865 ms 1

64 bytes from 200.198.87.5: icmp_seq=1 ttl=228 time=328.980 ms 64 bytes from 200.198.87.5: icmp_seq=2 ttl=228 time=324.031 ms 64 bytes from 200.198.87.5: icmp_seq=3 ttl=228 time=327.908 ms ^ trl- % 320msec 160msec 160msec 1.2? ( ) : a. PU b. 1 1 c. 1 d. 1 e. (LAN Local Area Network ) (WAN Wide Area Network ) 1.3 option ( ) (2 ) 2

( m m) LAN 2: ( ) ( 2) ( ) ( ) ( ) 1 LAN 1 LAN WAN ( ) WAN WAN 1-1 (NSPIXP Network Service Provider Internet exchange Point) ( 3) 1.4 3

LAN WAN WAN WAN NSPIXP WAN 3: ( ) ( ) ( ) A B D E F AtoF BtoE AtoF AtoF BtoE BtoE 4: 4 A F D F D F D D 1 1 1 D F 4

B E D B E A F 1 1 (IPv4) (IP ) 4 (32 ) IP 16 4 0 255. 32 (16 ) 0a020205 4 0a 02 05 10.2.2.5 google.co.jp? IP IP 16 1 OS 1.5 /* recv.c -- packet receiving example. */ #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> main(int argc, char *argv[]) { int fd, len, fromlen; char buf[100]; static struct sockaddr_in adr; adr.sin_family = AF_INET; A F E 5

} adr.sin_addr.s_addr = INADDR_ANY; adr.sin_port = htons(atoi(argv[1])); if((fd = socket(pf_inet, SOK_DGRAM, IPPROTO_UDP)) < 0 bind(fd, (struct sockaddr*)&adr, sizeof(adr)) < 0) { perror("socket: "); exit(1); } while(1) { len = recvfrom(fd, buf, 100, 0, 0, &fromlen); if(len < 0) { perror("recvfrom: "); exit(1); } write(1, buf, len); } #include... main fd ( ) len fromlen buf adr fd bind ( ) OS ( ) recvfrom OS recvfrom buf recvfrom write IP ifconfig( /sbin/ifconfig ) ifconfig ( ) % /sbin/ifconfig em0: flags=8843<up,broadast,running,simplex,multiast> mtu 1500 options=3<rxsum,txsum> inet 10.3.25.20 netmask 0xff000000 broadcast 10.255.255.255 ether 00:0f:ea:10:4c:71 media: Ethernet autoselect (1000baseTX <full-duplex>) status: active plip0: flags=8810<pointopoint,simplex,multiast> mtu 1500 lo0: flags=8049<up,loopbak,running,multiast> mtu 16384 inet 127.0.0.1 netmask 0xff000000 % inet(ip ) 127.0.0.1 10.3.25.20 IP IP % gcc -o recv recv.c % recv ( ) 0 65535 1024 ( ) 6

/* send.c -- packet sending example. */ #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> main(int argc, char *argv[]) { int fd; char buf[20]; int len; struct sockaddr_in adr; adr.sin_family = AF_INET; adr.sin_addr.s_addr = INADDR_ANY; if((fd = socket(pf_inet, SOK_DGRAM, IPPROTO_UDP)) < 0 bind(fd, (struct sockaddr*)&adr, sizeof(adr)) < 0) { perror("socket: "); exit(1); } adr.sin_port = htons(atoi(argv[1])); adr.sin_addr.s_addr = inet_addr(argv[2]); while((len = read(0, buf, 20)) > 0) { if(sendto(fd, buf, len, 0, (struct sockaddr*)&adr, sizeof(adr)) < 0) { perror("sendto: "); exit(1); } } } sendto IP % gcc -o send send.c recv % send IP hello. this is a pen.... recv ( trl- ) send % less t aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb ccccccccccccccccccccccccccccccccccccccccccccccccccccccccc ddddddddddddddddddddddddddddddddddddddddddddddddddddddddd aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb... % cat t t t t send recv ( ) aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb ccccccccccccccccccccccccccccccccccccccccccccccccccccccccc 7

ddddddddddddddddddddddddddddddddddddddddddddddddddddddddd... aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb bbbbbbbbbbbbbbbbbbb?...??? ( 4096 ) 2 2.1 (layered architecuture) FAX ( 5) 5: ( )? ( 6) 8

1. 2. 3. 4. 8 5 6 7 3 4 4 2 1 OK 2 OK 4 OK 6 3 5 6: ( ) ( ) 2.2?? ( ) a. a. ( ) a. b. c. d. e. 9

( ) ( ) ( ) ( ) 2.3 OSI ISO( ) (OSI Open System Interconnect) 7 OSI 7 7 Application Application a) Presentation Presentation Session Session b) Transport Transport c) Network Network Network Network d) Data Link Data Link Data Link Data Link e) Physical X Physical Physical Y Physical 7: OSI 7 1. ( e) 2. ( d) 3. ( c) 4. ( b) a OSI 5. / / 6. 7. ( ) 10

( ) ( TP/IP ) 2.4 TP/IP TP/IP TP/IP IPv4 IPv6 IPv4 TP/IP 8 rwho tftp wall telnet ftp smtp nntp rlogin rcp rexec nis NFS Application Presentation Session UDP TP Transport Internet Protocol (IP) Network loopback Ethernet Driver PPP Data Link Ethernet Serial/ADSL Physical 8: TP/IP IP(Internet Protocol) ( ) IP P LAN? IP UDP(User Datagram Protocol) TP(Transmission ontrol Protocol) UDP TP TP/IP 11

3 3.1 LAN LAN (Ethernet) LAN 1970 Xerox IEEE 802.3 ( 2 ) ( 9) Hub Switch 9: Ethernet 1 48 MA MA 1 ( ) ( ) SMA/D(arrier Sense Multiple Access/ollision Detection) SMA/D ( ) Mac ( ) 10Mbps 1Gbps 100m / IP ( 3 ) LAN WPA(Wi-Fi Protected Access) WPA2(Wi-Fi Protected Access 2) WPS(Wi-Fi Protected Setup) ( LAN ) 3 2 10Mbit/ 3 4Mbit/ 3 LAN WEP(Wireless Encription Privacy) 2 12

3.2 option LAN 2 ( ) 2 / PPP (Point-to-Point Protocol) PPP ADSL 8 ( )? A B 2 B A B A A A ( )? 2 (VPN) 3.3 Unix ifconfig ( ) ifconfig netstat -I netstat -I netstat -I 2 ( ) % netstat -I fxp0 1 input (fxp0) output packets errs bytes packets errs bytes colls 13

0 0 0 0 0 0 0 1 0 160 0 0 226 0 2 0 675 3 0 2056 0 3 0 60 2 0 66 0 2 0 0 3 0 0 0 1 0 941 0 0 785 0 3 0 41961 4 0 27492 0 36 0 19145 32 0 17968 0 56 0 67193 50 0 60948 0 33 0 38244 30 0 57064 0 118 0 0 111 0 0 0 2 0 0 2 0 0 0 0 0 0 0 0 0 0 ^ ontrol- % 4 4.1 IP IP TP/IP IP 32 IP IP ( ifconfig IP ) 1 IP IP 32 45 1 ( ) 1 IP IP ( IP ) ( ) IP 1 ( ) IANN(Internet orporation for Assigned Names and Numbers) http://www.icann.org/ JPNI http://www.nic.ad.jp/ 4 32 8 16 24 ( A B ) 5 192.168.0.0 192.168.0.0/24 / 1 32 ( ) 192.168.0.0 netmask 0xffffff00 14

( ) IP IP 32 IP IP(IPv6) IP 128 IPv4 IP ( ) ( ) NAT(Network Address Translation) NAT IP IPv6 ( ) IP ping ping ping IP IP / 4.2 IP ( ) 3? 1-1-1 15

IP 32 ( ) ( 10 ) 1 ( A B ) (default) A B 10: 1 (aggregate) 1 10.1.0.0/24 10.1.255.0/24 256 10.1.0.0/16 1 ( 11) 6 ( ) traceroute 6 1 16

(10.1.0.0/16) 10.1.0.2/24 10.1.0.0/24 10.1.0.1/24 11: ( ) % /usr/sbin/traceroute www.museuhistoriconacional.com.br traceroute to museuhistoriconacional.com.br (200.198.87.5), 64 hops max, 40 byte packets 1 plalagw (210.154.96.161) 1.306 ms 0.429 ms 0.331 ms 2 218.44.77.194 (218.44.77.194) 1.840 ms 1.985 ms 2.325 ms 3 218.44.77.193 (218.44.77.193) 2.499 ms 2.662 ms 2.363 ms 4 218.47.158.169 (218.47.158.169) 2.911 ms 2.537 ms 2.886 ms 5 218.43.251.249 (218.43.251.249) 3.086 ms 3.245 ms 2.493 ms 6 221.184.4.5 (221.184.4.5) 3.155 ms 2.970 ms 2.902 ms 7 210.145.252.153 (210.145.252.153) 3.039 ms 3.567 ms 2.773 ms 8 61.207.0.150 (61.207.0.150) 3.438 ms 2.737 ms 3.447 ms 9 xe-1-3-0.a21.tokyjp01.jp.ra.verio.net (61.120.145.189) 3.708 ms 3.432 ms 2.964 ms 10 xe-1-0-0.r20.tokyjp01.jp.bb.verio.net (61.213.162.229) 11.963 ms 3.381 ms 2.596 ms 11 129.250.4.41 (129.250.4.41) 120.197 ms 117.723 ms 121.253 ms 12 p64-1-3-0.r21.snjsca04.us.bb.verio.net (129.250.5.3) 119.417 ms 118.924 ms 119.250 ms 13 xe-0-2-0.r20.snjsca04.us.bb.verio.net (129.250.2.72) 118.523 ms 118.969 ms 118.863 ms 14 interconnect-eng.sanjose1.level3.net (209.245.146.241) 113.397 ms 117.990 ms 113.287 ms 15 so-3-2-0.bbr2.sanjose1.level3.net (4.68.121.197) 118.736 ms 114.859 ms 120.566 ms 16 as-1-0.mp1.miami1.level3.net (64.159.0.1) 199.557 ms as-0-0.mp2.miami1.level3.net (64.159.3.249) 199.404 ms as-1-0.mp1.miami1.level3.net (64.159.0.1) 205.298 ms 17 ge-9-1.hsa2.miami1.level3.net (64.159.0.22) 195.430 ms unknown.level3.net (64.159.1.178) 200.684 ms ge-9-0.hsa2.miami1.level3.net (64.159.0.14) 199.673 ms 18 unknown.level3.net (63.209.150.98) 199.561 ms 199.290 ms 194.934 ms 19 diveo-tb-mia-stm1.ipb.diveo.net.br (200.215.189.98) 313.151 ms 308.485 ms 313.937 ms 20 h200-215-179-9.ipb.diveo.net.br (200.215.179.9) 307.939 ms 375.406 ms 307.562 ms 21 200.202.113.49 (200.202.113.49) 313.544 ms 308.473 ms 312.274 ms 22 cl-s0-5521040038-cpe.rt.rjo.ipaccess.diveo.net.br (200.198.80.254) 329.319 ms 330.050 ms 323.844 ms 23 anita.visualnet.com.br (200.198.87.5) 328.080 ms 322.645 ms 323.022 ms 17

4.3 DNS IP IP ( ) Unix /etc/hosts IP ( OS ) 127.0.0.0 localhost 192.168.0.1 piyo01... IP IP LAN IP? IP DNS(Domain Name System) (DNS UDP IP ). ( ) www.gssm.otsuka.tsukuba.ac.jp www.gssm.otsuka.tsukuba.ac.jp DNS DNS (TLD Top-Level Domain) TLD.jp.ac.jp.co.jp.ac.jp.tsukuba.ac.jp DNS.otsuka.tsukuba.ac.jp DNS IP ( ) 18

TLD.jp( ).uk( ) TLD.com( ).edu( ) gtld(generic TLD TLD) IP IANA gtld IANA (.com VeriSign ) TLD ( JPRS) gtld DNS ( IP ) nslookup DNS nslookup IP % /usr/sbin/nslookup www.yahoo.co.jp. Server: utogw.gssm.otsuka.tsukuba.ac.jp Address: 192.50.17.2 Non-authoritative answer: Name: www.yahoo.co.jp Addresses: 202.229.198.216, 203.141.35.113, 210.81.150.5 % IP 3 WWW IP DNS? DNS DNS DNS? DNS DNS 5 5.1 UDP TP TP UDP 2 UDP IP UDP UDP ( IP ) ( ) (best effort) UDP UDP ( ) 19

TP (reliable) TP / ( ) TP W TP 01101 11011 11100 11011 00011 10010 checksum=10010 sender 9 8 7 6 5 4 1ok 2ok 3ok receiver 12: TP 5.2 IP ( ) ( ) 20

TP UDP 16 0 1023 (well-konwn ports) TP UDP ( IANA ) Unix /etc/services TP UDP netstat -f inet netstat -f inet TP UDP % netstat -f inet less Active Internet connections Proto Recv-Q Send-Q Local Address Foreign Address (state) tcp4 0 0 sma.nfsd smp.798 ESTABLISHED tcp4 0 0 sma.nfsd smri06.1019 ESTABLISHED tcp4 0 0 sma.49244 smr04.x11 ESTABLISHED tcp4 0 0 sma.canna smm.36645 ESTABLISHED tcp4 0 0 sma.nfsd smr04.1017 ESTABLISHED tcp4 0 0 sma.canna smri21.50085 ESTABLISHED tcp4 0 0 sma.nfsd smri21.999 ESTABLISHED tcp4 0 0 sma.nfsd smri17.1011 ESTABLISHED tcp4 0 0 sma.nfsd smr05.987 ESTABLISHED tcp4 0 0 sma.nfsd utogw.788 ESTABLISHED tcp4 0 0 localhost.smtp *.* LISTEN udp4 0 0 localhost.ntp *.* udp4 0 0 sma.ntp *.* udp4 0 0 localhost.1019 localhost.1022 % tcp4 udp4 IPv4 TP UDP. /etc/services TP ( ) 6 OSI 7 3 TP/IP ( ) TP/IP ( ) 21

TP/IP 7 4-1. WWW /sbin/ping (ping ) Windows 4-2. /usr/sbin/traceroute Windows tracert 4-3. nslookup IP WWW 4-4. send.c/recv.c ifconfig -a IP 2 netstat -f inet netstat 1 4-5. send.c/recv.c 3 4-6. netstat -f inet TP/IP netstat Windows netstat -a 4-7. netstat 1 1 Windows netstat -e 1 : (4-1 4-2 4-3) rlogin utogw utogw Windows ( ) 7 7 : recv.c send.c 2 2 22