[30070] in North American Network Operators' Group
Re: RFC 1918
daemon@ATHENA.MIT.EDU (Steven M. Bellovin)
Fri Jul 14 15:54:01 2000
From: "Steven M. Bellovin" <smb@research.att.com>
To: gary miller <gem@rellim.com>
Cc: Bennett Todd <bet@rahul.net>, nanog@merit.edu
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Date: Fri, 14 Jul 2000 15:47:22 -0400
Message-Id: <20000714194722.AD3EA35DC2@smb.research.att.com>
Errors-To: owner-nanog-outgoing@merit.edu
In message <Pine.LNX.4.21.0007141236200.16371-100000@ns1.aplatform.com>, "Gary
E. Miller" writes:
>
>Yo Bennet!
>
>Sounds like circular reasoning:
>
>Path MTU discovery is broken beacuse poeple use RFC1918 addresses in routers.
>
>Since Path MTU discovery is broken then there is no need to follow RFC1918.
No -- 1918 addresses would only break PMTU if folks did ingress or
egress filtering for 1918 addresses. A much bigger cause of the
breakage firewalls that block the ICMP message. And most people don't
notice or care, because there's been so little need for PMTU in recent
years. But that will change, as assorted tunneling technologies become
more popular.
--Steve Bellovin
