Net Tools : How to observe the net

ifconfig : know your IP Number(s) and interface(s)

> ifconfig

lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
inet6 ::1 prefixlen 128
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1
inet 127.0.0.1 netmask 0xff000000
gif0: flags=8010<POINTOPOINT,MULTICAST> mtu 1280
stf0: flags=0<> mtu 1280
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
tunnel inet -->
inet6 fe80::203:93ff:fe85:3724%en0 prefixlen 64 scopeid 0x4
ether 00:03:93:85:37:24
media: autoselect (10baseT/UTP <half-duplex>) status: active
supported media: none autoselect 10baseT/UTP <half-duplex> 10baseT/UTP <half-duplex,hw-loopback> 10baseT/UTP <full-duplex> 10baseT/UTP <full-duplex,hw-loopback> 100baseTX <half-duplex> 100baseTX <half-duplex,hw-loopback> 100baseTX <full-duplex> 100baseTX <full-duplex,hw-loopback> 1000baseTX <full-duplex> 1000baseTX <full-duplex,hw-loopback> 1000baseTX <full-duplex,flow-control> 1000baseTX <full-duplex,flow-control,hw-loopback>
en1: flags=8822<BROADCAST,SMART,SIMPLEX,MULTICAST> mtu 1500
tunnel inet -->
ether 00:30:65:1d:23:48
media: autoselect (<unknown type>) status: inactive
supported media: autoselect
ppp0: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1492
inet 203.221.196.72 --> 203.221.196.1 netmask 0xffffff00