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

Toerless Eckert <tte@cs.fau.de> Sun, 26 August 2018 21:29 UTC

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Date: Sun, 26 Aug 2018 23:29:13 +0200
From: Toerless Eckert <tte@cs.fau.de>
To: Joel Jaeggli <joelja@bogus.com>
Cc: Mikael Abrahamsson <swmike@swm.pp.se>, int-area <int-area@ietf.org>, intarea-chairs@ietf.org
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Subject: Re: [Int-area] WG Adoption Call: IP Fragmentation Considered Fragile
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On Sat, Aug 25, 2018 at 01:46:47PM -0700, Joel Jaeggli wrote:
> It's actually not that useful if it's an icmp message. because it's
> going to fail in many cases where it has to be hashed to a destination.
> just  like non-initial fragements do...
> 
> 4821 gets you there with tcp.

Its meant to support 4821 in good networks. Its fine to always have
higher layer solutions that spend a lot of effort to work
in the worst possible networks below them, but that should not mean
that do not try to make the network below work better. That's all
that ICMP means to do - on the premise that we should open a door
of allowing networks NOT to support fragmented packets.

Cheers
    Toerless

> > Of course. Will take a decade to get ubiquitously deployed, but
> > neither IPv4 nor IPv6 will go away, only the problems with fragmentation
> > will become worse and work if we do not have an exit strategy like this.
> It's not going to be ubiquitously deployed because it's not going to work.
> > If we don't try an exit strategy like this, we will just get what
> > Joe said, the complete segmentation of the Internet with more and
> > more L4 or even higher layer proxies.
> >
> > Btw: +1 for adopting the doc as a WG item, but primarily because everything
> > before section 7 is on a way to become a good read of reality. Section
> > 7 recommendations is only a faith based exercise (praying) as long as it tries to
> > get the job done primarily by appealing to application developers.
> >
> > Cheers
> >     Toerless
> >
> >
> >
> > _______________________________________________
> > Int-area mailing list
> > Int-area@ietf.org
> > https://www.ietf.org/mailman/listinfo/int-area
> >

pub   DSA 1024/B67F56B2 2003-08-11 Joel Jaeggli <joelja@bogus.com>
> sub ELG-E 4096/29407F92 2003-08-11