Re: [trill] AD review and progressing of draft-ietf-trill-rfc6439bis-03

Donald Eastlake <> Wed, 21 December 2016 00:14 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id 017AB1296C6; Tue, 20 Dec 2016 16:14:09 -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 autolearn_force=no
Authentication-Results: (amavisd-new); dkim=pass (2048-bit key)
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id ezsNofUYW0bf; Tue, 20 Dec 2016 16:14:08 -0800 (PST)
Received: from ( [IPv6:2607:f8b0:4001:c0b::22b]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by (Postfix) with ESMTPS id 37EA8129B4A; Tue, 20 Dec 2016 16:14:08 -0800 (PST)
Received: by with SMTP id 75so18967202ite.1; Tue, 20 Dec 2016 16:14:08 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=RGgZRO5zt0IjzOToBpK5e4rWnFtYeKGZQNNsKAIWcwY=; b=Fmcs0tDVo1Yyly11AQfzrGpUCIpyk8LmKFXNqfgk3bThtJVjBh18diIpvTDRSi642d HA8Obz9/4naxL2/1gEfiGZEdXvsIbqUAeYC5gGZtda4tB7fou3LY+707bLJxgC4V4sye BC3M/UHRyn+5AuAAxeyKy1DPjGC9TYZXRimIzBmgiUEVj0XkWcaoEZVNykOYAjh0phIV fQ8hQ++vi9Q7R06uj9bkZiwxziXha/HdW6c06OrXFdsD4NqtiYYj7/kgQBMneqhRUPTX 3lkAAjWSGg9Ep0pFB8ZU6bRzjfA/Qdq+D1oiemNq1y+hQZvOmG+/k0zix1/aEFnstRaF jQ3Q==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=RGgZRO5zt0IjzOToBpK5e4rWnFtYeKGZQNNsKAIWcwY=; b=Sby4HAH9sDv2Nx6b9or5aql1VtwCPECqI6b7+X4O49d+CgaBtJE9g4sIPaKV3aGeqE /knSQQbRVxEiWa3FyYoT/JHNSE8TmtBJ4PtSln0jejXipKlj2qwNLOVHNheZm1vJVSBY yi2/8V81+Pjj0CGW6YVVuWRznCCoyT13xoS8bYhyJ7ewJkT2tIFNUbaxtRnY3U8D80hB fM/Ce74RTP5isR0d13IBAsjkYKjvyBnVjeZ+cKiDaQlv7hyIjzEY0Aj4lgDGkCitI7Ff Re70Ilr+SrAYCmQP839MTsbwON2ZKmGmC0efCk8pGodWgIsZwVfmovhpRhrvPRGWwJoj T7mw==
X-Gm-Message-State: AIkVDXInu/zA6+Xt3c//qxufRR6+sZmy6VozuuQmcfYY6oaYNfvTku56/jyqWpnqgwUKK5ORvRr/1kz7VfqHYg==
X-Received: by with SMTP id x63mr2825472itg.14.1482279247473; Tue, 20 Dec 2016 16:14:07 -0800 (PST)
MIME-Version: 1.0
Received: by with HTTP; Tue, 20 Dec 2016 16:13:51 -0800 (PST)
In-Reply-To: <>
References: <>
From: Donald Eastlake <>
Date: Tue, 20 Dec 2016 19:13:51 -0500
Message-ID: <>
To: Alia Atlas <>
Content-Type: text/plain; charset=UTF-8
Archived-At: <>
Cc:, "" <>
Subject: Re: [trill] AD review and progressing of draft-ietf-trill-rfc6439bis-03
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: "Developing a hybrid router/bridge." <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Wed, 21 Dec 2016 00:14:09 -0000

Hi Alia,

On Tue, Dec 20, 2016 at 5:28 PM, Alia Atlas <> wrote:
> As is customary, I have done my AD review of draft-ietf-trill-rfc6439bis-03.
> First, I would like to thank the authors - Donald, Yizhou, Mohammed, Ayan and Fengwei - for their work on thsi well-written document.
> I do not have any specific comments on the draft from my review.   I have requested IETF Last Call and placed the draft on the January 19 telechat.

Thanks for you review of this draft and of

> I am slightly concerned by the complexity and number of different options that TRILL has in most aspects - but given that there is WG consensus and plans to implement, I am merely expressing my concerns.

I would guess you are primarily talking about the various methods by
which the Designated RBridge on a link can appoint forwarders in a
loop safe way. The design in the TRILL base protocol (RFC 6325) used
the non-framentable Appointed Forwarders TLV in non-fragmentable IS-IS
Hello PDUs that have a limited size. This was recognized as a problem.
So when IS-IS was extended to provide link (circuit) local link state
in RFC 7356, the forwarder appointment mechanism was specified via the
link local link state. There is additional complexity in making this
backwards compatible. It would have been cleaner to do it that way
from the start but the link local link state was not available.

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

> Regards,
> Alia