Subject: [L2tpext] Suresh Krishnan's Discuss on draft-ietf-l2tpext-keyed-ipv6-tunnel-07: (with DISCUSS)

From: "Suresh Krishnan" <[email-masked]>
Date: Wed, 02 Nov 2016 21:04:30 -0700

Suresh Krishnan has entered the following ballot position for
draft-ietf-l2tpext-keyed-ipv6-tunnel-07: Discuss

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DISCUSS:
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* Section 5
I am having a hard time seeing how fragmentation is expected to work 

   It is NOT RECOMMENDED for routers implementing this specification to
   enable IPv6 fragmentation (as defined in section 4.5 of RFC2460) for
   keyed IP tunnels.  IP fragmentation issues for L2TPv3 are discussed
   in section 4.1.4 of RFC3931.

And that specific section of RFC3931 recommends using RFC2473 to tunnel
the packets which again ends up using the RFC2460 fragment header that
this draft is trying to forbid.

So, can you please clarify exactly what happens when the size of the
packet to be tunneled exceeds the MTU?