Re: Review of draft-ietf-tram-turn-server-discovery-08

Ralph Droms <rdroms.ietf@gmail.com> Wed, 07 September 2016 10:42 UTC

Return-Path: <rdroms.ietf@gmail.com>
X-Original-To: ietf@ietfa.amsl.com
Delivered-To: ietf@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 7A30612B306; Wed, 7 Sep 2016 03:42:09 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.699
X-Spam-Level:
X-Spam-Status: No, score=-2.699 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com
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 5AOUT9mOIGQQ; Wed, 7 Sep 2016 03:42:07 -0700 (PDT)
Received: from mail-qk0-x231.google.com (mail-qk0-x231.google.com [IPv6:2607:f8b0:400d:c09::231]) (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 AC57512B2F8; Wed, 7 Sep 2016 03:42:06 -0700 (PDT)
Received: by mail-qk0-x231.google.com with SMTP id w204so7343205qka.0; Wed, 07 Sep 2016 03:42:06 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:mime-version:from:in-reply-to:date:cc:message-id:references :to; bh=tTazVfJBiQ4lisx6tGDY0nzJJIeyDvszgL9UmqCwwGA=; b=qrN0AJEXghnIsK239RcjdiZXNgRtbovNAsMebZqssKUacOEvkoiUNl1IgR9PEjooky QFsXCiQe7c0zq8vUmRNwmuOBKkg6+PdjZWz/Q17mUjFoASQf7/9+0K8rVzKaTWmloyAz aGizN7jq8RWAnZaXuCD/v1KYxftTZ8nw38Kilsc/914Ag8MCXOddKRnDdcLNGl3kRXow EU9diveaVlBx7g0D7SyMic1SW1zLNP7qW5HuHg8Q1Hcoh+rO5zEJvwLbQRhyCtQyiQAU 5XR5T5ZcWbLWOAZFifhlb6Q6QexxsLM1Vld8PLXBD4raqFOh9GE7shI+vztILHheScco PPIw==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:mime-version:from:in-reply-to:date:cc :message-id:references:to; bh=tTazVfJBiQ4lisx6tGDY0nzJJIeyDvszgL9UmqCwwGA=; b=Lhpwm90IySrlDYbywvw21STtohbzCNfvDw23KX1AQ3KN3FCppGktkIp18E8HlHyHej qpaon8R3eo9wZ6FbtJMB9E/VOrdvRi2SGnywzFYTBuf8Oi84dJXwey43z4Sa7U/ByXfS UYuUBQ8IkR32XoBClQP1Rrk++TdewTkO+r+W6OQD9pp1zZICm9avoVtw8dO9zsyDZH6l Qw4JhVi5x1jxJ+bHY0OKdM5Bm3+0Y3XTUedEjGIYj8xuvxqU5wp1f8qhOFo4mszrYB5T BIV31l3DFFT6xBXS327I2P/pkED82YfmvuWt8yjkaplKZmb9h8OhFeh4/UaG98+w0M8y iH5g==
X-Gm-Message-State: AE9vXwP5X+io6k4ooo/cjE9I85UgxhmugvpfIzi5iaCqhEJWvDTe1Z5rjWrG+SUqJNqb4g==
X-Received: by 10.55.6.148 with SMTP id 142mr17270282qkg.142.1473244925864; Wed, 07 Sep 2016 03:42:05 -0700 (PDT)
Received: from rtp-vpn1-766.cisco.com ([173.38.117.73]) by smtp.gmail.com with ESMTPSA id 6sm20723110qke.5.2016.09.07.03.42.04 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 07 Sep 2016 03:42:04 -0700 (PDT)
Subject: Re: Review of draft-ietf-tram-turn-server-discovery-08
Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\))
Content-Type: multipart/signed; boundary="Apple-Mail=_51208538-35A8-4B27-8C2A-11FFD413C54B"; protocol="application/pgp-signature"; micalg=pgp-sha256
X-Pgp-Agent: GPGMail
From: Ralph Droms <rdroms.ietf@gmail.com>
In-Reply-To: <3f00a2b2173b4c3794c39349ba21aa84@XCH-RCD-017.cisco.com>
Date: Wed, 7 Sep 2016 06:42:04 -0400
Message-Id: <03E7D42F-0107-410C-A96F-CEFF221B1301@gmail.com>
References: <7194DC7F-E802-42B2-AA6C-94D02167D89D@gmail.com> <89c07464407c404ea8543bcb3c3dc88e@XCH-RCD-017.cisco.com> <2EE5CFE0-F2A9-40AE-AAF2-D5DAFEA614CF@gmail.com> <8de72f2dba854efea00cd49d2b4d7923@XCH-RCD-017.cisco.com> <F08210DA-F45B-4AE7-8824-5E989310E855@piuha.net> <C4DE113C-E570-4E31-A660-765DC2406596@gmail.com> <3f00a2b2173b4c3794c39349ba21aa84@XCH-RCD-017.cisco.com>
To: "Tirumaleswar Reddy (tireddy)" <tireddy@cisco.com>
X-Mailer: Apple Mail (2.3124)
Archived-At: <https://mailarchive.ietf.org/arch/msg/ietf/JfjwsQ-autXjBi7ZWZ4Zq5uKCy0>
Cc: "draft-ietf-tram-turn-server-discovery.all@ietf.org" <draft-ietf-tram-turn-server-discovery.all@ietf.org>, "Review Area gen-art@ietf.org Team" <gen-art@ietf.org>, IETF discussion list <ietf@ietf.org>
X-BeenThere: ietf@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: IETF-Discussion <ietf.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ietf>, <mailto:ietf-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ietf/>
List-Post: <mailto:ietf@ietf.org>
List-Help: <mailto:ietf-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ietf>, <mailto:ietf-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 07 Sep 2016 10:42:09 -0000

> On Sep 6, 2016, at 11:34 PM 9/6/16, Tirumaleswar Reddy (tireddy) <tireddy@cisco.com> wrote:
> 
> Hi Ralph,
> 
> Please see inline [TR]
> 
> From: Ralph Droms [mailto:rdroms.ietf@gmail.com <mailto:rdroms.ietf@gmail.com>]
> Sent: Thursday, September 1, 2016 4:36 PM
> To: Jari Arkko <jari.arkko@piuha.net <mailto:jari.arkko@piuha.net>>
> Cc: Tirumaleswar Reddy (tireddy) <tireddy@cisco.com <mailto:tireddy@cisco.com>>; draft-ietf-tram-turn-server-discovery.all@ietf.org <mailto:draft-ietf-tram-turn-server-discovery.all@ietf.org>; Review Area gen-art@ietf.org <mailto:gen-art@ietf.org> Team <gen-art@ietf.org <mailto:gen-art@ietf.org>>; IETF discussion list <ietf@ietf.org <mailto:ietf@ietf.org>>
> Subject: Re: Review of draft-ietf-tram-turn-server-discovery-08
> 
> I just completed a quick review of draft-ietf-tram-turn-server-discovery-08.  The DNS Service Discovery section is much improved.  I have a couple of comments on the revised text:
> 
> 
> I suggest adding a reference to the IANa "Service Name and Transport Protocol Port Number Registry", http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=Turn <http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=Turn>, as the source of the service  names "turn" and "turns".
> 
> [TR] Will refer to RFC5766 which introduced the above service names.

OK.

> 
> While the example DNS records for "exampleco TURN Server" are technically correct, they would most likely be generated by the DNS-SD/mDNS library in a server, rather than appearing in a DNS server zone file somewhere.  For clarity, it might be better to use the unicast DNS versions of the DNS-SD records by substituting "example.com <http://example.com/>" for "local".
> 
> [TR] May be I am missing something, https://tools.ietf.org/html/rfc6763#section-4.1.1 <https://tools.ietf.org/html/rfc6763#section-4.1.1> says the instance name will not be machine-generated and will be a user-friendly name.

Right - the instance name, in this case "example TURN Server", is a configured, user-friendly name.  But the responses to mDNS queries for, e.g., _turn._udp.local. and "exampleco TURN Server"._turn._udp.local. will be generated by the DNS-SD/mDNS code on the host providing the service instance.

It's just a minor point...

> 
> In my opinion, the details in section 5.1 are redundant with and (possibly) not identical to the specification in RFC 6762 and RFC 6763.  Specifically, Figure 1 includes a typo; there should be separate A/AAAA query and reply messages.  More generally, DNS-SD/mDNS servers may return the SRV, TXT, A and AAAA records in the first reply, as an optimization.  I think it would be better, in this document, to specify simply that TURN servers and clients use the message exchanges specified in those RFCs for TURN server discovery.
> 
> [TR] Sure, will remove the figure.

OK.

- Ralph

> 
> Thanks and Regards,
> -Tiru
> 
> 
> 
> 
> - Ralph
> 
> 
> On Sep 1, 2016, at 4:05 AM, Jari Arkko <jari.arkko@piuha.net <mailto:jari.arkko@piuha.net>> wrote:
> 
> Ralph, Tiru — thanks for the updates and the review. I’ve looked at the change draft and I think it is fine now.
> 
> Jari
> 
>