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

Fernando Gont <fernando@gont.com.ar> Fri, 27 July 2018 12:50 UTC

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To: Joe Touch <touch@strayalpha.com>, Wassim Haddad <wassim.haddad@ericsson.com>
Cc: "internet-area@ietf.org" <int-area@ietf.org>, "intarea-chairs@ietf.org" <intarea-chairs@ietf.org>
References: <F227637E-B12D-45AA-AD69-74C947409012@ericsson.com> <0466770D-C8CA-49BB-AC10-5805CFDFB165@strayalpha.com>
From: Fernando Gont <fernando@gont.com.ar>
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Date: Fri, 27 Jul 2018 14:38:26 +0200
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Subject: Re: [Int-area] WG Adoption Call: IP Fragmentation Considered Fragile
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Hi, Joe,

On 07/26/2018 04:14 AM, Joe Touch wrote:
> Hi, all,
> 
> 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.
> 
> 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.
> 
> But I agree *some* statement is worthwhile here. My primary concern is that if we’re not careful, endorsing the status quo will only ensure nothing changes.

FWIW, I see and understand your point. However, based on the operational
implications of fragmentation, it believe it is *extremely* unlikely
that the situation improves (if at all possible).

So my take is that this I-D rather than endorsing the status quo, is
essentially warning possible users of what it may happen with their
fragmented traffic.

Side coments:

It would all seem that there are two operating environments:
* Controlled environments, where you can somehow make all this work
* Public internet, which is more of a "fingers crossed" thing (if anything).

I'm not saying that I'm happy with the outcome, but rather that I think
that from an engenering point of view, it all looks like this ship has
sailed, and we should probably figure out how to deal with those cases
where fragmentation is actually needed.

Thanks!

Cheers,
-- 
Fernando Gont
e-mail: fernando@gont.com.ar || fgont@si6networks.com
PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1