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

Ole Troan <otroan@employees.org> Fri, 27 July 2018 20:28 UTC

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From: Ole Troan <otroan@employees.org>
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Date: Fri, 27 Jul 2018 22:28:24 +0200
Cc: Fernando Gont <fernando@gont.com.ar>, Tom Herbert <tom@herbertland.com>, "internet-area@ietf.org" <int-area@ietf.org>, "intarea-chairs@ietf.org" <intarea-chairs@ietf.org>
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To: Brian E Carpenter <brian.e.carpenter@gmail.com>
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Subject: Re: [Int-area] WG Adoption Call: IP Fragmentation Considered Fragile
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> On 27 Jul 2018, at 22:12, Brian E Carpenter <brian.e.carpenter@gmail.com> wrote:
> 
> Fragmentation, (PL)PMTUD, extension headers, and innovative
> L4 protocols are very possibly not viable on the open Internet.
> At least, we can't assume that they will work on arbitrary paths.
> Sad but apparently true.

Hasn’t this been discussed ad infinitum in the ossification work?
If you want to generalize, nothing is guaranteed to work across an arbitrary path in the Internet. 

So what? This is part of a tussle and it would be making a self fulfilling prophecy for us to take all policy based filtering or other brokenness into consideration when designing protocols. 

Ole