...
*Arpanet
*switched network
*TCP/IP
*spread in the 90's
...
*strict procedure how things are done
*communication between layers
*clearly defined interfaces
*data encapsulation
*example
TCP/IP protocol
*Application
*Transport
*Network
*Physical / Data link
from wikipedia
Physical layer / Data link layer
...
private networks that are not routed
Code Block |
---|
10.0.0.0 - 10.255.255.255 (10/8 prefix)
172.16.0.0 - 172.31.255.255 (172.16/12 prefix)
192.168.0.0 - 192.168.255.255 (192.168/16 prefix)
|
localhost 127.0.0.0/8
"network addresses" ending with 0
"broadcast addresses" ending with 255
routing
nat
configuration
...
*connections through ports
*well known ports <1024 can be found in /etc/services
Code Block |
---|
~$ cat /etc/services
# Network services, Internet style
#
# Note that it is presently the policy of IANA to assign a single well-known
# port number for both TCP and UDP; hence, officially ports have two entries
# even if the protocol doesn't support UDP operations.
#
# Updated from http://www.iana.org/assignments/port-numbers and other
# sources like http://www.freebsd.org/cgi/cvsweb.cgi/src/etc/services .
# New ports will be added on request if they have been officially assigned
# by IANA and used in the real-world or are needed by a debian package.
# If you need a huge list of used numbers please install the nmap package.
tcpmux 1/tcp # TCP port service multiplexer
echo 7/tcp
echo 7/udp
discard 9/tcp sink null
discard 9/udp sink null
systat 11/tcp users
daytime 13/tcp
daytime 13/udp
netstat 15/tcp
qotd 17/tcp quote
msp 18/tcp # message send protocol
msp 18/udp
chargen 19/tcp ttytst source
chargen 19/udp ttytst source
ftp-data 20/tcp
ftp 21/tcp
fsp 21/udp fspd
ssh 22/tcp # SSH Remote Login Protocol
ssh 22/udp
telnet 23/tcp
smtp 25/tcp mail
time 37/tcp timserver
time 37/udp timserver
rlp 39/udp resource # resource location
nameserver 42/tcp name # IEN 116
whois 43/tcp nicname
tacacs 49/tcp # Login Host Protocol (TACACS)
tacacs 49/udp
re-mail-ck 50/tcp # Remote Mail Checking Protocol
re-mail-ck 50/udp
domain 53/tcp # name-domain server
domain 53/udp
mtp 57/tcp # deprecated
tacacs-ds 65/tcp # TACACS-Database Service
tacacs-ds 65/udp
bootps 67/tcp # BOOTP server
bootps 67/udp
bootpc 68/tcp # BOOTP client
bootpc 68/udp
tftp 69/udp
gopher 70/tcp # Internet Gopher
gopher 70/udp
rje 77/tcp netrjs
finger 79/tcp
www 80/tcp http # WorldWideWeb HTTP
www 80/udp # HyperText Transfer Protocol
....snip....
|
...
Application Layer
...
DNS
HTTP
SSH
Tools
ifconfig
sample output of ifconfig
Code Block |
---|
eth0 Link encap:Ethernet HWaddr 00:19:D1:93:AE:EA
inet addr:192.168.10.1 Bcast:192.168.10.255 Mask:255.255.255.0
inet6 addr: fe80::219:d1ff:fe93:aeea/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:20 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:0 (0.0 b) TX bytes:3345 (3.2 KB)
Base address:0x30c0 Memory:90300000-90320000
eth1 Link encap:Ethernet HWaddr 00:80:48:51:A5:31
inet addr:192.168.0.100 Bcast:192.168.0.255 Mask:255.255.255.0
inet6 addr: fe80::280:48ff:fe51:a531/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3364 errors:0 dropped:0 overruns:0 frame:0
TX packets:2897 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3753263 (3.5 MB) TX bytes:488792 (477.3 KB)
Interrupt:21 Base address:0xe800
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:74 errors:0 dropped:0 overruns:0 frame:0
TX packets:74 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:8537 (8.3 KB) TX bytes:8537 (8.3 KB)
|
ip
output of ip route
Code Block |
---|
192.168.0.0/24 dev eth1 proto kernel scope link src 192.168.0.100
192.168.10.0/24 dev eth0 proto kernel scope link src 192.168.10.1
default via 192.168.0.1 dev eth1 metric 100
|
ping
output of ping
Code Block |
---|
ping 65.212.180.178
PING 65.212.180.178 (65.212.180.178) 56(84) bytes of data.
64 bytes from 65.212.180.178: icmp_seq=1 ttl=50 time=396 ms
64 bytes from 65.212.180.178: icmp_seq=2 ttl=50 time=420 ms
64 bytes from 65.212.180.178: icmp_seq=3 ttl=50 time=394 ms
--- 65.212.180.178 ping statistics ---
4 packets transmitted, 3 received, 25% packet loss, time 3010ms
rtt min/avg/max/mdev = 394.577/403.996/420.659/11.838 ms
|
tracepath
output of tracepath
Code Block |
---|
tracepath 65.212.180.178
1: 192.168.0.100 (192.168.0.100) 0.188ms pmtu 1492
1: 192.168.1.2 (192.168.1.2) asymm 36 4.262ms
2: 192.168.1.1 (192.168.1.1) asymm 102 5.671ms
3: 59.92.64.1 (59.92.64.1) asymm 4 119.448ms
4: 218.248.255.10 (218.248.255.10) 141.537ms
5: 218.248.255.10 (218.248.255.10) asymm 4 136.279ms
6: 220.227.53.238 (220.227.53.238) 160.888ms
7: 62.216.145.81 (62.216.145.81) asymm 17 433.441ms
8: so-6-0-0.0.cjr01.ldn004.flagtel.com (62.216.128.145) asymm 16 432.633ms
9: 82.195.188.21 (82.195.188.21) asymm 14 411.295ms
10: sl-bb22-lon-8-0.sprintlink.net (213.206.128.60) asymm 13 418.883ms
11: sl-bb20-nyc-2-0.sprintlink.net (144.232.9.163) asymm 13 433.378ms
12: sl-bb26-nyc-6-0.sprintlink.net (144.232.13.9) asymm 14 415.121ms
13: 144.232.8.194 (144.232.8.194) asymm 15 427.211ms
14: tbr1.n54ny.ip.att.net (12.122.81.10) asymm 22 425.951ms
15: cr1.n54ny.ip.att.net (12.122.16.161) asymm 21 442.912ms
16: cr1.cgcil.ip.att.net (12.122.1.190) asymm 20 429.262ms
17: cr1.st6wa.ip.att.net (12.122.31.162) asymm 19 439.363ms
18: tbr1.st6wa.ip.att.net (12.122.23.154) 445.856ms
19: gbr1.st6wa.ip.att.net (12.122.12.158) asymm 17 440.989ms
20: gar1.ptdor.ip.att.net (12.123.44.121) asymm 15 422.986ms
21: 12.118.177.66 (12.118.177.66) asymm 13 421.216ms
22: po1.ir1.cvo2.kattare.net (204.13.9.2) asymm 14 420.901ms
23: ground1.kattare.com (65.212.180.178) asymm 15 437.003ms reached
Resume: pmtu 1492 hops 23 back 15
|
dig
dig bluelightav.org
Code Block |
---|
; <<>> DiG 9.4.1-P1 <<>> bluelightav.org
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 52347
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2
;; QUESTION SECTION:
;bluelightav.org. IN A
;; ANSWER SECTION:
bluelightav.org. 2724 IN A 65.212.180.178
;; AUTHORITY SECTION:
bluelightav.org. 2724 IN NS ns1.kattare.com.
bluelightav.org. 2724 IN NS ns2.kattare.com.
;; ADDITIONAL SECTION:
ns1.kattare.com. 170390 IN A 69.59.195.60
ns2.kattare.com. 170390 IN A 204.13.11.60
;; Query time: 0 msec
;; SERVER: 192.168.10.1#53(192.168.10.1)
;; WHEN: Sat Apr 12 13:39:40 2008
;; MSG SIZE rcvd: 128
|
content of /etc/network/interfaces
Code Block |
---|
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet static
address 192.168.10.1
network 192.168.10.0
netmask 255.255.255.0
broadcast 192.168.10.255
gateway 192.168.0.1
auto eth1
iface eth1 inet static
address 192.168.0.100
network 192.168.0.0
netmask 255.255.255.0
broadcast 192.168.0.255
gateway 192.168.0.1
|