Re: [Int-area] WG Adoption Call: IP Fragmentation Considered Fragile

Ole Troan <otroan@employees.org> Fri, 27 July 2018 12:37 UTC

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Date: Fri, 27 Jul 2018 14:37:34 +0200
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Cc: Wassim Haddad <wassim.haddad@ericsson.com>, "internet-area@ietf.org" <int-area@ietf.org>, "intarea-chairs@ietf.org" <intarea-chairs@ietf.org>
To: Joe Touch <touch@strayalpha.com>
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Subject: Re: [Int-area] WG Adoption Call: IP Fragmentation Considered Fragile
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Joe,

> I still think it would be useful for this doc to describe how tunnels interact with fragmentation (per draft-ietf-intarea-tunnels), which seems to be something I’ve noted several times before.

There's nothing intrinsic in tunnels that require network layer fragmentation. The current IP in IP / GRE etc tunnel implementations do, but in principle we could design tunnel fragmentation/reassembly above the network layer.

> I’m also still not thrilled with the title I’d be happier with “IP fragmentation still not supported per requirements”, and I’d have to see where this goes with final recommendations.

If we were to conclude that IP fragmentation is done at the wrong layer...

Cheers,
Ole