Re: [trill] Fwd: Mail regarding draft-ietf-trill-over-ip

Tom Herbert <tom@herbertland.com> Tue, 05 May 2015 18:53 UTC

Return-Path: <tom@herbertland.com>
X-Original-To: trill@ietfa.amsl.com
Delivered-To: trill@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id BFDB91B2F7E for <trill@ietfa.amsl.com>; Tue, 5 May 2015 11:53:26 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.978
X-Spam-Level:
X-Spam-Status: No, score=-1.978 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, FM_FORGED_GMAIL=0.622, RCVD_IN_DNSWL_LOW=-0.7] autolearn=unavailable
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 RRjCOSHE_Y0s for <trill@ietfa.amsl.com>; Tue, 5 May 2015 11:53:22 -0700 (PDT)
Received: from mail-ig0-f178.google.com (mail-ig0-f178.google.com [209.85.213.178]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id EA7801B2F76 for <trill@ietf.org>; Tue, 5 May 2015 11:53:21 -0700 (PDT)
Received: by igbyr2 with SMTP id yr2so111168422igb.0 for <trill@ietf.org>; Tue, 05 May 2015 11:53:21 -0700 (PDT)
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=ex0jXvkuZDnFD9AKBH7p9gnLudQ2dBhV23OV7K1+qIc=; b=IqdcZmMbQ/xafMB6TtNEaQWYxs8cvoGL2gmgDRFK+U5VbQNKHoumrPL9SBnmudDziW wkhXRnSK7DdczXvBH24sxbhX5mG1gvbfp9Rx5o/F2gws63IeTrB06NIwwYhWsd1z6Elk bHcuPjUrN8z3OJ1zc7TSqujJltll1z3CWbwM0nJjaKS20JwonrBquU5Vn+B6jLA0Wvdi HFnK1OT36nsOWJwW1yvxPBHoEbAPyovInJtB2N8MUZlaobz90i9SnPIMsbC93/neZ7uo nnz5z/foYcHrKCZUYOoPDDp2pF5FkuFkW+ydRhkUw1HVSCJp9exjQkdnA8e3nER/xIab Q/OA==
X-Gm-Message-State: ALoCoQnovr2CLyM6Oe5YNl4Wf5ZD946JcEoiP7GkXpAqc2zMW8tsN+GxrsAAlqJ/8khzgP9y/1Qg
MIME-Version: 1.0
X-Received: by 10.50.142.67 with SMTP id ru3mr3668851igb.16.1430852001441; Tue, 05 May 2015 11:53:21 -0700 (PDT)
Received: by 10.107.160.2 with HTTP; Tue, 5 May 2015 11:53:21 -0700 (PDT)
In-Reply-To: <2134F8430051B64F815C691A62D9831832E5AC5F@XCH-BLV-504.nw.nos.boeing.com>
References: <4552F0907735844E9204A62BBDD325E76ABADC85@nkgeml512-mbx.china.huawei.com> <CAF4+nEHSGYa+1DHzwee+RNgkXfZra_Pa9706vqpTGJV71SmDaw@mail.gmail.com> <CAF4+nEFcUL2ieQKCm98_0XxfrrAR0M11irVFfOfqa=92OM1V=A@mail.gmail.com> <5543D870.6080108@isi.edu> <1FEE3F8F5CCDE64C9A8E8F4AD27C19EE0832A468@NKGEML512-MBS.china.huawei.com> <55479A6D.2040403@isi.edu> <1FEE3F8F5CCDE64C9A8E8F4AD27C19EE0832A7B7@NKGEML512-MBS.china.huawei.com> <2134F8430051B64F815C691A62D9831832E5A834@XCH-BLV-504.nw.nos.boeing.com> <5548F132.7050704@isi.edu> <2134F8430051B64F815C691A62D9831832E5A90F@XCH-BLV-504.nw.nos.boeing.com> <5549039C.2020709@isi.edu> <2134F8430051B64F815C691A62D9831832E5ABBE@XCH-BLV-504.nw.nos.boeing.com> <55490B41.2000207@isi.edu> <2134F8430051B64F815C691A62D9831832E5AC5F@XCH-BLV-504.nw.nos.boeing.com>
Date: Tue, 05 May 2015 11:53:21 -0700
Message-ID: <CALx6S35nHEMvaSNis_uPQ6t4rm2NSzFN2Jzoo8WaXj04RdH3NQ@mail.gmail.com>
From: Tom Herbert <tom@herbertland.com>
To: "Templin, Fred L" <Fred.L.Templin@boeing.com>
Content-Type: text/plain; charset="UTF-8"
Archived-At: <http://mailarchive.ietf.org/arch/msg/trill/1cGsbmBEZKXi0u39I2aUFdcuzes>
Cc: "int-area@ietf.org" <int-area@ietf.org>, "sfc@ietf.org" <sfc@ietf.org>, Joe Touch <touch@isi.edu>, "nvo3@ietf.org" <nvo3@ietf.org>, "trill@ietf.org" <trill@ietf.org>, Donald Eastlake <d3e3e3@gmail.com>, Xuxiaohu <xuxiaohu@huawei.com>
Subject: Re: [trill] Fwd: Mail regarding draft-ietf-trill-over-ip
X-BeenThere: trill@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: "Developing a hybrid router/bridge." <trill.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/trill>, <mailto:trill-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/trill/>
List-Post: <mailto:trill@ietf.org>
List-Help: <mailto:trill-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/trill>, <mailto:trill-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 05 May 2015 18:53:26 -0000

On Tue, May 5, 2015 at 11:47 AM, Templin, Fred L
<Fred.L.Templin@boeing.com> wrote:
> Hi Joe,
>
>> -----Original Message-----
>> From: Joe Touch [mailto:touch@isi.edu]
>> Sent: Tuesday, May 05, 2015 11:26 AM
>> To: Templin, Fred L; Xuxiaohu; Donald Eastlake; trill@ietf.org
>> Cc: nvo3@ietf.org; int-area@ietf.org; sfc@ietf.org
>> Subject: Re: [trill] Fwd: Mail regarding draft-ietf-trill-over-ip
>>
>>
>>
>> On 5/5/2015 11:04 AM, Templin, Fred L wrote:
>> > Hi Joe,
>> >
>> >> -----Original Message-----
>> >> From: Joe Touch [mailto:touch@isi.edu]
>> >> Sent: Tuesday, May 05, 2015 10:54 AM
>> >> To: Templin, Fred L; Xuxiaohu; Donald Eastlake; trill@ietf.org
>> >> Cc: nvo3@ietf.org; int-area@ietf.org; sfc@ietf.org
>> >> Subject: Re: [trill] Fwd: Mail regarding draft-ietf-trill-over-ip
>> >>
>> >>
>> >>
>> >> On 5/5/2015 9:39 AM, Templin, Fred L wrote:
>> >>> Hi Joe,
>> >> ..
>> >>>> IP in UDP adds only port numbers and an Internet checksum.
>> >>>>
>> >>>> That doesn't address fragmentation; if outer fragmentation is assumed,
>> >>>> IPv4 needs to be rate-limited to avoid ID collisions and the Internet
>> >>>> checksum is insufficient to correct those collisions.
>> >>>
>> >>> Right - that is why we have GUE. But, when these functions are not
>> >>> needed GUE can perform header compression and the result looks
>> >>> exactly like IP in UDP.
>> >>
>> >> That seems impossible.
>> >
>> > Not impossible - Tom Herbert provided the solution:
>> >
>> > http://www.ietf.org/mail-archive/web/int-area/current/msg04593.html
>>
>> That is allocating bits (or bit patterns) from the IP header.
>>
>> The solution provided - to check for 0x01 - is incorrect. IP can have
>> versions that include 0x10 and 0x11.
>
> The version field in both IPv4 and IPv6 have that bit set to 1. If GUE
> then deems that bit to indicate "direct IP encapsulation, then there
> is no need for a GUE header of length greater than 0.
>
> You may say that future IP protocol versions might not have that bit
> set in the version field. But, the version bits for IPv4 and IPv6 will
> never change (by definition) and we do not see a new IP protocol
> version replacing IPv4 or IPv6 on the near-term horizon.
>
> Even if a new IP protocol version emerged with the "direct IP
> encapsulation" bit set to 0, that version can still be accommodated
> by GUE. It's just that direct encapsulation cannot be used and a
> non-zero-length GUE header is needed.
>
Or just define a simple version translation as part of encapsulation.
So for IPv8:

0x1000->0x0101 on encapsulation
0x0101->0x1000 on decapsualtion

> Thanks - Fred
> fred.l.templin@boeing.com
>
>> The only solution would be to say that if the first three bits were 0,
>> then it's not an IP packet - but that would require reassigning 0x0000
>> and 0x0001 for GUE purposes.
>>
>> Although that's possible, I don't see why we would allocate IP versions
>> to GUE message types.
>>
>> Joe
>
> _______________________________________________
> trill mailing list
> trill@ietf.org
> https://www.ietf.org/mailman/listinfo/trill