Re: [Isis-wg] Fwd: New Version Notification for draft-franke-isis-over-ipv6-00.txt

Donald Eastlake <> Mon, 23 November 2015 05:09 UTC

Return-Path: <>
Received: from localhost ( []) by (Postfix) with ESMTP id 630EF1B364F for <>; Sun, 22 Nov 2015 21:09:52 -0800 (PST)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -1.75
X-Spam-Status: No, score=-1.75 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, SPF_PASS=-0.001] autolearn=no
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id uV1WEOfwmYHf for <>; Sun, 22 Nov 2015 21:09:50 -0800 (PST)
Received: from ( [IPv6:2607:f8b0:4003:c06::231]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by (Postfix) with ESMTPS id 7C9641B364B for <>; Sun, 22 Nov 2015 21:09:50 -0800 (PST)
Received: by oiww189 with SMTP id w189so111204625oiw.3 for <>; Sun, 22 Nov 2015 21:09:49 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type; bh=CwJ5kVFrD/L9SScmrJmnBh4fFiyVxml4c5xvZ9x+/LQ=; b=ksRwMmJ5wyzAnSsQwrsBpMaW1Ja7Flk8v8aGwYBoARAdnfZ8Bo9x2g444MbUUsTlBh YMhgCuT+cJxXaevpCFxnCN0xUsOiDK6OrSU2/SS3oiYCcnVlmk95tOpPA6fvPNu26aOC CEescHt7gUecojsMVXPPrVtwmil5K8od/PAzRWXHcTCo7if25utDK6wGgMzE4SQz016J qsn2byi3WBkwMUF+J6TMfKNnhO+pVtAH5N0kmoSclMXqmLihx/ci/L/kI9R18caZaDuy j39CJWoBz7xHoQWeBxJyj0naWA5Gnk68QFfLPVD7JsCQmbBvh67L4qRty4KLqsuoidWR 8UlA==
X-Received: by with SMTP id dm1mr16333516oeb.16.1448255389720; Sun, 22 Nov 2015 21:09:49 -0800 (PST)
MIME-Version: 1.0
Received: by with HTTP; Sun, 22 Nov 2015 21:09:35 -0800 (PST)
In-Reply-To: <>
References: <> <>
From: Donald Eastlake <>
Date: Mon, 23 Nov 2015 00:09:35 -0500
Message-ID: <>
To: Christian Franke <>
Content-Type: text/plain; charset=UTF-8
Archived-At: <>
Cc: isis mailing list <>
Subject: Re: [Isis-wg] Fwd: New Version Notification for draft-franke-isis-over-ipv6-00.txt
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: IETF IS-IS working group <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Mon, 23 Nov 2015 05:09:52 -0000


In order to be able to treat an IP network as a link type between
TRILL routers, TRILL needs to be able to send TRILL IS-IS packets
between TRILL routers in a manner that does not interact with use of
IS-IS within the IP network. So I've thought a fair amount about IS-IS
over IP. There has been a TRILL WG draft on this for some time.

I think you are right that the correct thing for IPv6 is to use the
port's IPv6 address as the SNPA.

Your isis-over-ipv6 draft says that SNPAs don't occur on the wire,
just within IS-IS routers. But I believe they occur in IS-IS Hellos.
See TLV #6, referred to as "IIS Neighbors" in IANA's TLV table and
shown in ISO/IEC 10589-2002 Second Edition in Clause 9.5, item "a",
page 68. I just checked and that IS-IS TLV is specified as being
limited to 48-bit SNPAs. Looking further, the ISO/IEC standard seems
to have a TLV #7, shown in item "b" on that page for specifying
neighbor SNPAs and that TLV #7 does have an SNPA length field so they
could be some other length. Maybe I'm confused, but, it appears that
the IETF has re-assigned TLV #7 to be Instance Identifier (RFC6822).
Since you say there are interoperable implementations of your draft,
am I confused or do they have some solution to the above problem?
Perhaps, since Hellos are link local, the implementations just use
fixed size 128-bit SNPAs in their IIS Neighbors TLVs over IPv6,
contrary to the ISO specification, and this was left out of the draft?

(This is not a problem for TRILL over IP as TRILL uses the TRILL
Neighbor TLV (#145, RFC 7176) which does provide an SNPA length

 Donald E. Eastlake 3rd   +1-508-333-2270 (cell)
 155 Beaver Street, Milford, MA 01757 USA

On Fri, Jul 3, 2015 at 2:50 PM, Christian Franke
<> wrote:
> Dear all,
> In this new draft, I'd like to propose an alternative method to transmit
> IS-IS PDUs. By using IPv6 as transport, it makes the protocol less
> dependent on specific link-layers.
> There are two interoperable free software implementations for this which
> will be published until the IETF in Prague and which will be presented
> there during Bits-N-Bites.
> I'd be happy to receive your feedback.
> -Christian
> -------- Forwarded Message --------
> Subject: New Version Notification for draft-franke-isis-over-ipv6-00.txt
> Date: Fri, 03 Jul 2015 11:27:10 -0700
> From:
> To: Christian Franke <>rg>, Christian Franke
> <>
> A new version of I-D, draft-franke-isis-over-ipv6-00.txt
> has been successfully submitted by Christian Franke and posted to the
> IETF repository.
> Name:           draft-franke-isis-over-ipv6
> Revision:       00
> Title:          IS-IS over IPv6
> Document date:  2015-07-03
> Group:          Individual Submission
> Pages:          5
> URL:
> Status:
> Htmlized:
> Abstract:
>    In this draft, a method to transmit IS-IS PDUs as IPv6 packets is
>    described.  While the default encapsulation of IS-IS is specified
>    directly on top of the link-layer, making it necessary for IS-IS to
>    be specified for each link-layer it should be used on, the proposed
>    method allows for IS-IS to run on any link-layers supporting IPv6.
> Please note that it may take a couple of minutes from the time of submission
> until the htmlized version and diff are available at
> The IETF Secretariat
> _______________________________________________
> Isis-wg mailing list