Re: [rtcweb] Summary of ICE discussion

Magnus Westerlund <magnus.westerlund@ericsson.com> Wed, 05 October 2011 08:06 UTC

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Date: Wed, 5 Oct 2011 10:09:32 +0200
From: Magnus Westerlund <magnus.westerlund@ericsson.com>
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To: Bernard Aboba <bernard_aboba@hotmail.com>
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Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] Summary of ICE discussion
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Hi,

good that my summary lets us move forward.

A question on this attack. How common is it that these STUN servers use
other ports than 3478? Would a rule about that port mitigate the issue,
even if it could result in connectivity failures in cases where the NAT
external port is 3478 by chance?

In addition does these public servers use the username and password
convention from ICE? Isn't that what prevents STUN server deployed for
just determining your server reflexive candidate from actually respond
correctly to a connectivity check? As ICE do concatenate one part
generated by one peer with a part generated by the other peer I don't
see this as an issue as long as the random username fragment is
generated by the browser not the JS.

Cheers

Magnus Westerlund

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