TCP/IP 详解 卷1 ch4 ARP

1. ARP : if you are the owner of this IP address, please respond to me with your hardware address (48 bits).

2. ARP cache

/home/a/j/nomad2:arp -a
Net to Media Table: IPv4
Device   IP Address               Mask      Flags   Phys Addr
------ -------------------- --------------- ----- ---------------
e1000g0 192.168.1.1          255.255.255.255       00:14:f6:44:2a:27
e1000g0 x4100.unix-center.net 255.255.255.255 SP    00:14:4f:45:f1:96
e1000g0 BASE-ADDRESS.MCAST.NET 240.0.0.0       SM    01:00:5e:00:00:00

arp for IP address that are not reachable

/home/a/j/nomad2:telnet 192.168.1.13
Trying 192.168.1.13...
telnet: Unable to connect to remote host: Connection refused
/home/a/j/nomad2:arp -a
Net to Media Table: IPv4
Device   IP Address               Mask      Flags   Phys Addr
------ -------------------- --------------- ----- ---------------
e1000g0 192.168.1.11         255.255.255.255       00:14:4f:1e:3f:9c
e1000g0 192.168.1.13         255.255.255.255       00:18:8b:f8:15:31
e1000g0 192.168.1.1          255.255.255.255       00:14:f6:44:2a:27
e1000g0 192.168.1.40         255.255.255.255       00:1d:09:f1:d2:d6
e1000g0 192.168.2.8          255.255.255.255       00:1d:09:0c:3d:94
e1000g0 x4100.unix-center.net 255.255.255.255 SP    00:14:4f:45:f1:96
e1000g0 192.168.1.12         255.255.255.255       00:18:8b:f8:14:4d
e1000g0 192.168.2.6          255.255.255.255       00:1d:09:0c:37:d4
e1000g0 192.168.2.7          255.255.255.255       00:1d:09:0c:3a:ef
e1000g0 192.168.2.199        255.255.255.255       00:0c:29:8e:e7:0f
e1000g0 192.168.2.219        255.255.255.255       08:00:27:84:d3:ca
e1000g0 192.168.2.221        255.255.255.255       08:00:27:8e:79:0a
e1000g0 BASE-ADDRESS.MCAST.NET 240.0.0.0       SM    01:00:5e:00:00:00

3. using tcpdump (in another machine) to check the ARP machanism

4. ARP proxy for routers