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

Ole Troan <otroan@employees.org> Tue, 31 July 2018 12:37 UTC

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From: Ole Troan <otroan@employees.org>
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Date: Tue, 31 Jul 2018 14:27:59 +0200
Cc: Tom Herbert <tom@herbertland.com>, "internet-area@ietf.org" <int-area@ietf.org>, intarea-chairs@ietf.org
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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,

>> The need for fragmentation cannot be completely
>> eliminated and we do need it to work. Devices that do things to
>> prevent correct operation still need to be fixed, and it would be
>> productive for the draft to include statements on how some of the
>> sub-problems problems can be fixed (like using flow label for ECMP
>> instead of ports).
> 
> On that we agree. That’s my key concern - how to do this in a way that doesn’t effectively kill off IP fragmentation for the rest of us.

For IPv4 it’s an unfortunate side-effect of the fact that we are out of IPv4 addresses. As we continue to increase the ratio of users per IPv4 address, IPv4 fragmentation, or any protocol that isn’t TCP or UDP are not going to work well in the public IPv4 Internet.
IPv4 Internet Architecture is evolving as a consequence of address run-out. I think we’ve pretty much explored the solution space for IPv4 sharing mechanisms, so I think you just have to accept this new and unimproved (sic) IPv4 Internet architecture.

Cheers,
Ole