From owner-freebsd-hackers  Wed Sep 20 13:28:59 1995
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Date: Wed, 20 Sep 95 16:28:31 PDT
From: "Ugen J.S.Antsilevich" <ugen@latte.worldbank.org>
Subject: RE: Firewalling one interface using IPFW? 
To: hackers@FreeBSD.ORG, Nate Williams <nate@trout.sri.MT.net>
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As far as i remember my own code( heh, i already forgot it for good)..
you have option "via" or "at" which both allow to set all the firewalls
for one interface only. Other interfaces would not be affected by the 
permissions...

--Ugen