RE: [2.4 PATCH] bugfix: ARP respond on all devices

On Maw, 2003-08-19 at 13:02, Richard Underwood wrote:

	ARP is local to a broadcast net. The ARP standard explicitly
prohibits responding to an ARP request on a different interface.

Correct, but we don't do that

	If you broadcast a request asking for a reply on an entirely
different subnet, you're asking for trouble. You REDUCE the likelyhood of a
successful ARP reply, not increase it.

You increase it and you shortcut on shared lans. Thats really a seperate
issue to the question of which source is used. If you loopback someone
elses address on your own lo device I'm not suprised weird shit happens,
put the alias on eth0 where it belongs.

	All you can possibly achieve by sending REQUESTS from the wrong IP
number is assist screwed up networks where you've got multiple subnets on
the same copper and cause a shed-load of security issues.

Not in general. If you are using ARP your lan is hardly "secure". For
most situations the trust across multiple aggregated lans is the same,
if it isnt people use vlan (which rarely helps 8))