Subject: Re: default route and private networks
To: David Young <dyoung@pobox.com>
From: Jonathan Stone <jonathan@dsg.stanford.edu>
List: tech-security
Date: 04/13/2005 17:43:54
In message <20050413234709.GR6156@che.ojctech.com>, David Young writes:
>On Wed, Apr 13, 2005 at 05:39:34PM -0400, Thor Lancelot Simon wrote:
>> On Wed, Apr 13, 2005 at 12:29:10PM -0500, David Young wrote:
>> >
>> > is preferred.  IPv4 should likewise prefer a private sources (192.168/16,
>> > 10/8, ...) when the destination is private, a link-local (169.254/16)
>> > for link-local destinations, and global source for a global destination.

IPv4 "should" do this?  Who is saying this, and on what authority?
I'm pretty sure this not a SHOULD in the sense of RFC-2119.


>> You want to be careful with this; it takes us even further away from the
>> "strong host model" and may break the assumptions of people who've built
>> certain kinds of firewalls.

Seconded. I would go further and change "may" to "will"; possibly
changing "people" to "some people".



>I don't think so---have you read the patch?
>
>(What is the canonical document on the weak host/strong host model, BTW?
>What are the canonical keywords, for that matter?  Google isn't pulling
>up anything of use.)

RFC-1122 is a common reference.  If you're _that_ under-informed, how
much credence should be given to your opinions on how IPv4 "should"
behave?