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Re: Non-Last Small IPv6 Fragments

"Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net> Fri, 11 January 2019 13:43 UTC

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From: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net>
To: 神明達哉 <jinmei@wide.ad.jp>
Cc: Timothy Winters <twinters@iol.unh.edu>, IPv6 IPv6 List <ipv6@ietf.org>
Subject: Re: Non-Last Small IPv6 Fragments
Date: Fri, 11 Jan 2019 13:43:03 +0000
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On 10 Jan 2019, at 18:55, 神明達哉 wrote:

> I don't see a reason why an implementation can drop such fragments.
> As you pointed out, the standard protocol doesn't prohibit it.  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, even if there's currently no implementation that
> actually does that.

Well that won’t work as 650 octets is not a multiple of 8 and hence 
the first fragment would be dropped.  You cannot just do size/2; that 
only works for every nth packet size (n to be determined by the reader 
;-) ).

/bz

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