IETF Logo Mail Archive

[rtcweb] Feedback for draft-ietf-rtcweb-mdns-ice-candidates-03

Nils Ohlmeier <nohlmeier@mozilla.com> Thu, 04 July 2019 05:26 UTC

Return-Path: <nohlmeier@mozilla.com>
X-Original-To: rtcweb@ietfa.amsl.com
Delivered-To: rtcweb@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 85D951200CE for <rtcweb@ietfa.amsl.com>; Wed, 3 Jul 2019 22:26:45 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2
X-Spam-Level:
X-Spam-Status: No, score=-2 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=mozilla.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 edikojVJBnz3 for <rtcweb@ietfa.amsl.com>; Wed, 3 Jul 2019 22:26:43 -0700 (PDT)
Received: from mail-pf1-x429.google.com (mail-pf1-x429.google.com [IPv6:2607:f8b0:4864:20::429]) (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 10D33120088 for <rtcweb@ietf.org>; Wed, 3 Jul 2019 22:26:42 -0700 (PDT)
Received: by mail-pf1-x429.google.com with SMTP id m30so2358317pff.8 for <rtcweb@ietf.org>; Wed, 03 Jul 2019 22:26:42 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mozilla.com; s=google; h=from:content-transfer-encoding:mime-version:subject:message-id:date :to; bh=cEPgc+6r9NWfaXGQC9XCSo/R0+wySHhcBUkZIspzdBU=; b=gUOBJevDGG0ESxrNnVggeqdlIt7afHGTLidv/iYoJDz0UBKInh8+dEmU0z6NGAS1zq rakdO9fELhchCy3bSqUPBIU11GNd5IwuNCq8XuUmBiKoSYFgYMzKDZAszt95H5lcZcUf x3/7TvJTabAGZeeVmYMgPLnVhetrgLq834WDI=
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:content-transfer-encoding:mime-version :subject:message-id:date:to; bh=cEPgc+6r9NWfaXGQC9XCSo/R0+wySHhcBUkZIspzdBU=; b=l4DEKtzxvVj/5ZkZD5JJ9Zbs7bn1mARWMwZLaL/lzz2PqiO0MuMPvBhqNlQTrSmg79 ehVo85/UBRLycnR0tmNNEJ9PCM2oOzwVigVXVY9SDwB3wSkBfLsD75aoH2WoiflBrqPu CZMFd++GaRCx9Uy6cw8UWh6gQVugEN5t1/OK9BwC0L7bk826zR0yJLv8ZUYCMwR4htcG H+8CKuNhhEVIWK2XGoHzvuFS+OEhmKkW+ife/N/eNh1bQ0Ls0JjBIXJmBYJWCxxnXZqD /1VRNrHlovmbmvXr4tr7pA8mPHHA+abBOzd75O0jX1ANwc/V26zyt14XDKulCfbfbWH6 uRvA==
X-Gm-Message-State: APjAAAVuaXE9zhLyfPT9w18cVldaJXsg8va9A6S9IHX4R+4VRZ5DG5nz lVtUizfUJXPyKvZw0FEekNAORT0D67Q=
X-Google-Smtp-Source: APXvYqwLIspCKs/xYagafm7qxj06aEZ00bY2WFDJHeR6OAPBY0HO7FQSx48HKxYRIZAOJ97pL/E4EQ==
X-Received: by 2002:a65:5888:: with SMTP id d8mr40500270pgu.124.1562218002020; Wed, 03 Jul 2019 22:26:42 -0700 (PDT)
Received: from ?IPv6:2601:647:4600:3f31:3126:36db:8c73:b0d5? ([2601:647:4600:3f31:3126:36db:8c73:b0d5]) by smtp.gmail.com with ESMTPSA id q10sm3543028pgg.35.2019.07.03.22.26.41 for <rtcweb@ietf.org> (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 03 Jul 2019 22:26:41 -0700 (PDT)
From: Nils Ohlmeier <nohlmeier@mozilla.com>
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: quoted-printable
Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\))
Message-Id: <29062AF1-579F-41F2-A2A6-633E4371BF1E@mozilla.com>
Date: Wed, 03 Jul 2019 22:26:40 -0700
To: "rtcweb@ietf.org" <rtcweb@ietf.org>
X-Mailer: Apple Mail (2.3445.104.11)
Archived-At: <https://mailarchive.ietf.org/arch/msg/rtcweb/AVD6LCyaQoy-6Xvlt-8P5fpGDho>
Subject: [rtcweb] Feedback for draft-ietf-rtcweb-mdns-ice-candidates-03
X-BeenThere: rtcweb@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Real-Time Communication in WEB-browsers working group list <rtcweb.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/rtcweb>, <mailto:rtcweb-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/rtcweb/>
List-Post: <mailto:rtcweb@ietf.org>
List-Help: <mailto:rtcweb-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/rtcweb>, <mailto:rtcweb-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 04 Jul 2019 05:26:46 -0000

Hello,

I have concerns regarding the current recommendations in draft-ietf-rtcweb-mdns-ice-candidates-03 regarding the handling of IP addresses in the “c=“ lines.

Section 3.1.2.3 recommends to use mDNS for the connection-address. I think we should reconsider this advice as some SPD parsers handle parsing failures differently depending on line type.
In case of Firefox a parsing failure for the connection line is treated as terminal failure. Where parsing failures for a= lines are expected, as these might contain unknown new features.

Section 4.3 mentions that hostnames in ICE candidates can result in ICE failures, but it does not cover backward compatibility in regards to the c= line.

My recommendation is to change the draft so that it recommends to always use a fixed value, for example IP6 ::1 in all c= lines, if mDNS is in use. Obviously it could also be recommended to use an IP4 address instead. The important point is only to use the same IP consistently in all c= lines and across all instances.
I think the advantage of this is better backwards compatibility, and it will not reveal any more details about the user agent compared to using mDNS names in c= lines.

Best regards
  Nils Ohlmeier

v2.23.0 | Report a Bug | By Email