Re: [v6ops] Some stats on IPv6 fragments and EH filtering on the Internet

Fernando Gont <> Tue, 05 November 2013 00:01 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id A211C21E80FB; Mon, 4 Nov 2013 16:01:27 -0800 (PST)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -2.3
X-Spam-Status: No, score=-2.3 tagged_above=-999 required=5 tests=[AWL=-0.300, BAYES_00=-2.599, J_CHICKENPOX_13=0.6, NO_RELAYS=-0.001]
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id uLn1ndTk1cxb; Mon, 4 Nov 2013 16:01:27 -0800 (PST)
Received: from ( [IPv6:2a00:d10:2000:e::3]) by (Postfix) with ESMTP id 2F22621E82E1; Mon, 4 Nov 2013 16:01:01 -0800 (PST)
Received: from [2001:5c0:1000:a:8000:0:1f85:a0d1] by with esmtpsa (TLSv1:DHE-RSA-CAMELLIA256-SHA:256) (Exim 4.80.1) (envelope-from <>) id 1VdU4p-000255-0i; Tue, 05 Nov 2013 01:00:59 +0100
Message-ID: <>
Date: Mon, 04 Nov 2013 16:00:53 -0800
From: Fernando Gont <>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0
MIME-Version: 1.0
To: Mikael Abrahamsson <>, Fernando Gont <>
References: <> <>
In-Reply-To: <>
X-Enigmail-Version: 1.5.2
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Cc: IPv6 Operations <>, "" <>
Subject: Re: [v6ops] Some stats on IPv6 fragments and EH filtering on the Internet
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: v6ops discussion list <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Tue, 05 Nov 2013 00:01:27 -0000

On 11/04/2013 03:32 PM, Mikael Abrahamsson wrote:
>> Certainly there's *much* more work to be done in this area, but I
>> thought that this could be good food sfor some of the discussions that
>> we were having on the topic.
> "Operators are known to filter IPv6 fragments". This kind of writing

Isn't there a v6ops I-D with similar wording?

> implies intent, right? 

mm... as far as discussion on a number of forums went, apparently
there's intent to do so.

> Most of the "filtering" I would say is due to
> default device behavior, where no intent exists on the operator.

Data? References?

> So I'd
> rather see this changes to "IPv6 fragment header packets are having a
> severely degraded network experience" or something like that.

Well, the preso is out there, already. :-(

> Otherwise, great work. I would like to see traceroute or alike done with
> these kinds of packets headers also, to see where packets are dropped.

Yep. This is in my TODO list. Hopefully we will cooperate with Tim
(Chown) et al to take these measurements further.

Fernando Gont
SI6 Networks
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492