Why use Proxy ARP with subnetting?
The applications for using Proxy ARP with subnetting are fairly specific. In my case, I had a wireless Ethernet card that plugs into an 8-bit ISA slot. I wanted to use this card to provide connectivity for a number of machines at once. Being an ISA card, I could use it on a Linux machine, after I had written an appropriate device driver for it – this is the subject of another document. From here, it was only necessary to add a second Ethernet interface to the Linux machine and then use some mechanism to join the two networks together. For the purposes of discussion, let network 0 be the local Ethernet connected to the Linux box via an NE-2000 clone Ethernet interface on eth0. Network 1 is the main network connected via the wireless Ethernet card on eth1. Machine A is the Linux box with both interfaces. Machine B is any TCP/IP machine on network 0 and machine C is likewise on network 1. Normally, to provide the connectivity, I would have done one of the following: • Used the IP-Bridge s
