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Re: Non-Last Small IPv6 Fragments

Carsten Bormann <cabo@tzi.org> Thu, 10 January 2019 23:30 UTC

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Subject: Re: Non-Last Small IPv6 Fragments
From: Carsten Bormann <cabo@tzi.org>
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Date: Fri, 11 Jan 2019 00:30:45 +0100
Cc: Timothy Winters <twinters@iol.unh.edu>, IPv6 IPv6 List <ipv6@ietf.org>
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To: 神明達哉 <jinmei@wide.ad.jp>
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On Jan 10, 2019, at 19:55, 神明達哉 <jinmei@wide.ad.jp> wrote:
> 
> I
> would even consider it "reasonable" (not just "allowed by the
> standard") if an implementation divides a 1300-octet packet into two
> 650-octet fragments (ignoring common header overhead for brevity)
> instead of 1280 + 20,

Actually, something more on the side of 20 + 1280 might also be a useful choice.

https://tools.ietf.org/html/draft-bormann-lwig-6lowpan-virtual-reassembly-00#section-4

That said, that example is more useful for adaptation layer fragmentation as in 6LoWPAN, and I fully sympathize with an IP implementation that might want to reject silly fragments.

Grüße, Carsten

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