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

Mikael Abrahamsson <swmike@swm.pp.se> Fri, 27 July 2018 08:21 UTC

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Date: Fri, 27 Jul 2018 10:21:20 +0200 (CEST)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: Tom Herbert <tom@herbertland.com>
cc: "Templin (US), Fred L" <Fred.L.Templin@boeing.com>, "internet-area@ietf.org" <int-area@ietf.org>, "intarea-chairs@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 Thu, 26 Jul 2018, Tom Herbert wrote:

> I don't understand what would be platform specific. Can you elaborate?

On one platform iperf3 sends MTU minus header sized UDP packet, without IP 
fragmentation (so ~1400 bytes UDP payload). On the other platform iperf3 
sends 8k UDP packets, fragmented by the IP stack if MTU is less than 8k.

I have no idea if this is an iperf3 version difference or platform 
specific, but this is what I see in my tcpdump:s.

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se