Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!ames!ucsd!ucsdhub!hp-sdd!hplabs!hpda!hp-sde!hpfcdc!hpldola!hp-lsd!hpcsla!bdale
From: bdale@hpcsla.HP.COM (Bdale Garbee)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: Proxy ARP (was Re: Dumb vs. smart host routing)
Message-ID: <210001@hpcsla.HP.COM>
Date: 27 May 88 22:38:50 GMT
References: <882@kaos.UUCP>
Organization: HP Colorado Springs Division
Lines: 27

/ srg@quick.COM (Spencer Garrett) /  2:15 am  May 18, 1988 /

>Why can't a host just ARP for any destination and expect the
>appropriate gateway(s) to answer?  If there were a hopcount
>field in the ARP record, I think this would solve all the problems.

We (N3CVL, K3MC, and myself) looked very hard about a year ago at 
doing something like this in the KA9Q
Internet Package, to improve the situation on amateur packet radio, where
almost noone can talk directly to anyone else, and so gateway/switch issues
become very important.

I eventually backed away from this idea when it became more clear to me that
a distinction can and perhaps should be maintained between "routing" which
is a logical operation, and "address resolution" which is (to me at least) a
purely physical operation.

However, my recent experience in designing and maintaining a sitewide LAN
at work, including a bunch of discless clusters that for reasons of performance
and cost will be subnetted by putting two ports on each discless server, have
led me to be very interested in Proxy ARP, and other "ARP extensions".  (If only
HP would officially support Proxy ARP in HP-UX... sigh)

My curiosity is up, therefore I also would be interested in comments on 
this subject.

Bdale, N3EUA