[netext] draft-ietf-netext-logical-interface-support -- multiple incompatible MTU advertisements?

"Charles E. Perkins" <charliep@computer.org> Wed, 16 November 2011 02:23 UTC

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Date: Tue, 15 Nov 2011 18:23:42 -0800
From: "Charles E. Perkins" <charliep@computer.org>
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Subject: [netext] draft-ietf-netext-logical-interface-support -- multiple incompatible MTU advertisements?
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Hello folks,

At the meeting this morning, a question was raised
about the proper behavior on a logical interface if
more than one value of MTU were advertised on any of
the links of the interface.  This was discussed in
the IPv6 working group.  IIRC, the sense of the
discussion was that this was simply an error.
See section 6.2.7 of RFC 4861.

In the case for logical interfaces, it seems to
me that (a) a device can pick the MTU for whatever
router advertisement it is using and (b) for the
purposes of multicast across all links the source
should pick the minimum of all advertised values.

Charlie P.

Charlie P.