Re: [MMUSIC] ICE candidate pairing and NAT64

🔓Dan Wing <> Wed, 24 June 2015 01:21 UTC

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From: 🔓Dan Wing <>
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Date: Tue, 23 Jun 2015 18:21:51 -0700
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Subject: Re: [MMUSIC] ICE candidate pairing and NAT64
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On 23-Jun-2015 12:28 pm, Jonathan Lennox <> 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?


> 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, so it must be relatively possible?