Re: [rtcweb] New use-case proposed

Harald Alvestrand <harald@alvestrand.no> Fri, 11 May 2012 20:52 UTC

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Date: Fri, 11 May 2012 22:52:14 +0200
From: Harald Alvestrand <harald@alvestrand.no>
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Subject: Re: [rtcweb] New use-case proposed
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On 05/11/2012 06:38 PM, Göran Eriksson AP wrote:
>
> 11 maj 2012 kl. 18:21 skrev "Harald Alvestrand"<harald@alvestrand.no>rand.no>:
>
>> I propose to reject this use case because it requires yet another
>> security redesign.
>> The clue is here:
>>
>>> - The keying solution must allow each participants to encrypt to
>>> multiple receivers without any decryption+encryption in the middle node
>>>
>> This means that each participant must use the same encryption keys to
>> all other participants; this in turn means that when someone leaves the
>> group, all participants must change their encryption keys; it also means
>> that as long as shared keys are used for authentication, all
>> participants can impersonate all other participants.
>>
>> In fact, this solution has most of the issues (except for the network
>> layer deployment issue) that leads me to strongly advocate leaving
>> multicast out of scope for this effort.
> You mean for this phase of webrtc std efforts or for ever?
Until we've got an usage scenario with a deployment story that I find 
credible.

The point I'm pretty vehement on - that lack of multicast support should 
not be a blocker for finalizing the specs we are working on.

               Harald