IETF Logo Mail Archive

Re: Running code (Was: I-D Action: draft-ietf-6man-ipv6only-flag-03.txt)

Simon Hobson <linux@thehobsons.co.uk> Sun, 28 October 2018 08:57 UTC

Return-Path: <linux@thehobsons.co.uk>
X-Original-To: ipv6@ietfa.amsl.com
Delivered-To: ipv6@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 033B712785F for <ipv6@ietfa.amsl.com>; Sun, 28 Oct 2018 01:57:56 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.9
X-Spam-Level:
X-Spam-Status: No, score=-1.9 tagged_above=-999 required=5 tests=[BAYES_00=-1.9] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id eDSqInY_zE-6 for <ipv6@ietfa.amsl.com>; Sun, 28 Oct 2018 01:57:54 -0700 (PDT)
Received: from patsy.thehobsons.co.uk (patsy.thehobsons.co.uk [80.229.10.150]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id E5B72126CC7 for <ipv6@ietf.org>; Sun, 28 Oct 2018 01:57:53 -0700 (PDT)
X-Quarantine-ID: <mwgexkbupSsW>
X-Virus-Scanned: Debian amavisd-new at patsy.thehobsons.co.uk
X-Amavis-Alert: BAD HEADER SECTION, Header line longer than 998 characters: References: <CA[...]
Received: from simons-macbookpro.thehobsons.co.uk (Simons-MacBookPro.thehobsons.co.uk [192.168.137.111]) by patsy.thehobsons.co.uk (Postfix) with ESMTPSA id 044101BC37 for <ipv6@ietf.org>; Sun, 28 Oct 2018 08:57:45 +0000 (UTC)
Content-Type: text/plain; charset="us-ascii"
Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2104\))
Subject: Re: Running code (Was: I-D Action: draft-ietf-6man-ipv6only-flag-03.txt)
From: Simon Hobson <linux@thehobsons.co.uk>
In-Reply-To: <308494108c0b466f91a9314f7d9367bc@boeing.com>
Date: Sun, 28 Oct 2018 08:57:45 +0000
Content-Transfer-Encoding: quoted-printable
Message-Id: <8E339E1C-6AC9-4012-AA63-1A39D64EEDAB@thehobsons.co.uk>
References: <CAFU7BASO_ByzbanhLKnWV280O_fASd-8W+ujpj3sN6d2-whw2w@mail.gmail.com> <C46C990E-0A4F-4731-8CB1-FD204858935E@consulintel.es> <9B53019C-3506-4C9E-AFCF-D6125FA1A65B@gmail.com> <1157b739-3a66-8d45-e3e1-e5f904dfb9bc@asgard.org> <a00607f9-7ced-f889-b5cb-c2fe16367d73@si6networks.com> <66759b73-0a22-e1a9-49db-21154e8e1267@gmail.com> <37ba23b3-df19-9c2a-bdbe-ba7a99d72d05@si6networks.com> <0d6008a4-337b-2ccb-2d9f-837f786eca65@gmail.com> <bfa4397a-aa7a-1184-4147-4cbfbfd13603@si6networks.com> <8C587906-F0EE-4A61-9046-2BF AC52588C0@isc.org> <E8DE18B5-94FC-411C-A310-E49A382E0079@thehobsons.co.uk> <e0fa8fad1b4249c9af79788323b0a922@boeing.com> <3A03A073-72E2-43A8-90A4-5C29DF445361@thehobsons.co.uk> <27fdbd71125842d888c5136684bf6e7b@boeing.com> <9A4368D6-E4B1-474C-9838-B584AF6D70C8@thehobsons.co.uk> <a3a2d823c38f44d48b301e2ca657e352@boeing.com> <6EE067A5-3536-4EDD-80D9-D98783DE57CE@thehobsons.co.uk> <0be69133e9a34199b5796410684ab226@boeing.com> <d84bab3c-3ad8-2338-1af1-3fe2b277db6c@innovat ionslab.net> <308494108c0b466f91a9314f7d9367bc@boeing.com>
To: "ipv6@ietf.org" <ipv6@ietf.org>
X-Mailer: Apple Mail (2.2104)
Archived-At: <https://mailarchive.ietf.org/arch/msg/ipv6/MXghIc0-lTK1cfRNcIFkx1B1I4s>
X-BeenThere: ipv6@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "IPv6 Maintenance Working Group \(6man\)" <ipv6.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ipv6>, <mailto:ipv6-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ipv6/>
List-Post: <mailto:ipv6@ietf.org>
List-Help: <mailto:ipv6-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ipv6>, <mailto:ipv6-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sun, 28 Oct 2018 08:57:56 -0000

Manfredi (US), Albert E <albert.e.manfredi@boeing.com> wrote:

>> OK, explain how the device is to know whether or not it should be turning on IPv4 to see if there's an IPv4 printer it needs to talk to ?
> 
> That should occur when you set up the printer, when you load the printer driver. In my own experience, I have had to enter the actual IP address, EVEN OF enterprise printers, when the DNS for some reason or other didn't contain its name. So that's one way the host can determine to use IPv4, for that printer.

You are still looking at this in a "this is my known network" manner.

You go onto a network you've not been on before, how does your device know whether it should be using IPv4 to look for a printer via mDNS ? If you turn on IPv4 to look for what could be a non-existent printer then you've missed the opportunity to save power, if you don't then you may not know about a printer that should be available to you.
There is no set of heuristics that will solve that for you. If you think there is, then write it down !

v2.23.0 | Report a Bug | By Email