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