Re: [MMUSIC] ICE candidate pairing and NAT64

🔓Dan Wing <dwing@cisco.com> Wed, 24 June 2015 01:21 UTC

Return-Path: <dwing@cisco.com>
X-Original-To: mmusic@ietfa.amsl.com
Delivered-To: mmusic@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 08BE51B3333 for <mmusic@ietfa.amsl.com>; Tue, 23 Jun 2015 18:21:55 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -14.211
X-Spam-Level:
X-Spam-Status: No, score=-14.211 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, MIME_8BIT_HEADER=0.3, RCVD_IN_DNSWL_HI=-5, SPF_PASS=-0.001, T_RP_MATCHES_RCVD=-0.01, USER_IN_DEF_DKIM_WL=-7.5] autolearn=ham
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 kcLtbVAqDtLu for <mmusic@ietfa.amsl.com>; Tue, 23 Jun 2015 18:21:53 -0700 (PDT)
Received: from alln-iport-2.cisco.com (alln-iport-2.cisco.com [173.37.142.89]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 201F61B3332 for <mmusic@ietf.org>; Tue, 23 Jun 2015 18:21:53 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=1391; q=dns/txt; s=iport; t=1435108913; x=1436318513; h=mime-version:subject:from:in-reply-to:date:cc: content-transfer-encoding:message-id:references:to; bh=t9MlJayAvqh2DbeypPQeCl3qL4pWTi5nGC/A9dFDlYQ=; b=Viy3vOw0kqdCH09OyQ56rkjaYlhNsgeux501rXvo2BkCbT1NZTTht5pH ZPmfof1gY4ThvzRL3Tq4S0j39RUoDETAFPyVYXSKj2vzWm57y6utVpwXw 71HyizZj5niz4h+5GiZWuJxm8Y48zWMR0DOWfDwO7dOB52NyyqB6Daa8j 0=;
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: A0C4CAAgBYpV/5pdJa1bgxBUX4MetimEKwmBZoV4AoFLOBQBAQEBAQEBgQpBA4NeAQEBAwEjVgULCxgCAiYCAlcGE4gnCA22UZZEAQEBAQEBAQEBAQEBAQEBAQEBAQEBF4EhiimEOxgzB4JoL4EUBYx9hwKLUYE6kyCDWyZjgzceMQGCRwEBAQ
X-IronPort-AV: E=Sophos;i="5.13,669,1427760000"; d="scan'208";a="162037575"
Received: from rcdn-core-3.cisco.com ([173.37.93.154]) by alln-iport-2.cisco.com with ESMTP; 24 Jun 2015 01:21:52 +0000
Received: from dhcp-10-155-84-100.cisco.com (dhcp-10-155-84-100.cisco.com [10.155.84.100]) by rcdn-core-3.cisco.com (8.14.5/8.14.5) with ESMTP id t5O1Lpnw010164 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 24 Jun 2015 01:21:52 GMT
Content-Type: text/plain; charset="utf-8"
Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2098\))
From: 🔓Dan Wing <dwing@cisco.com>
In-Reply-To: <CA8D917B-8C7C-42B9-BF65-F7209DFCA15C@vidyo.com>
Date: Tue, 23 Jun 2015 18:21:51 -0700
Content-Transfer-Encoding: quoted-printable
Message-Id: <64FC711B-0B70-4489-A08B-8218DA80BF77@cisco.com>
References: <CA8D917B-8C7C-42B9-BF65-F7209DFCA15C@vidyo.com>
To: Jonathan Lennox <jonathan@vidyo.com>
X-Mailer: Apple Mail (2.2098)
Archived-At: <http://mailarchive.ietf.org/arch/msg/mmusic/hBpdoXbZdEdBKiBuaus03iw8eiU>
Cc: mmusic <mmusic@ietf.org>
Subject: Re: [MMUSIC] ICE candidate pairing and NAT64
X-BeenThere: mmusic@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Multiparty Multimedia Session Control Working Group <mmusic.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/mmusic>, <mailto:mmusic-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/mmusic/>
List-Post: <mailto:mmusic@ietf.org>
List-Help: <mailto:mmusic-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mmusic>, <mailto:mmusic-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 24 Jun 2015 01:21:55 -0000

On 23-Jun-2015 12:28 pm, Jonathan Lennox <jonathan@vidyo.com> wrote:
> 
> Apple’s recent announcement that all iOS apps are soon going to be required to support running behind NAT64 has led me to contemplate what this means for ICE.
> 
> Should ICE endpoints be required and/or recommended to support using RFC 7050 NAT64 prefix discovery to pair local IPv6 candidates which have a NAT64 gateway with remote IPv4 candidates?

Yes.

> What does this do to connectivity check pacing, or to the total number of connectivity checks?

It means an IPv6-only device with a NAT64 has same number of candidates as a dual-stack device.  I would pace and prioritize NAT64 addresses exactly same as IPv4 addresses would be paced and prioritized on a dual-stack host.

> And how many operating systems can support a userspace app doing an RFC 7050 DNS lookup on a per-interface basis?  (Even if you roll your own DNS resolver, you still need to be able to obtain per-interface DNS server configuration information to find the interface’s appropriate DNS64 server.)

Dunno.  MIF was going to solve that.  I will note that dnsmasq appears capable of sending DNS requests out certain interfaces (see the --server option at http://www.thekelleys.org.uk/dnsmasq/docs/dnsmasq-man.html), so it must be relatively possible?

-d