Re: [MLS] TreeKEM: An alternative to ART

Benjamin Kaduk <kaduk@mit.edu> Thu, 10 May 2018 23:25 UTC

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Date: Thu, 10 May 2018 18:25:12 -0500
From: Benjamin Kaduk <kaduk@mit.edu>
To: Alexey Ermishkin <scratch@virgilsecurity.com>
Cc: mls@ietf.org
Message-ID: <20180510232511.GD84491@kduck.kaduk.org>
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Subject: Re: [MLS] TreeKEM: An alternative to ART
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On Wed, May 09, 2018 at 11:38:06PM +0500, Alexey Ermishkin wrote:
> Hello everyone,
> 
> There’s a use case which I think should be taken into consideration. 
> 
> IoT.
> 
> I myself had no idea about it but it turns out IoT devices often communicate in groups like one group for one apartment/room/building, etc. And they do broadcasting all the time to each other.
> 
> Prerequisites is that every device knows either other device’s public keys or a root key that signs each of them so that could establish trust.
> 
> The second thing that I know is that right now there’s a complex procedure which involves transmitting a symmetric group key to each member of the group using whatever they have now like ECIES.
> 
> And I believe MLS can help with that.

Perhaps.  I'll note that I did raise IoT at the BoF, and the sense
of the room seemed to be that it was out of scope.  That said, the
draft charter should be going out for community review real soon
now, and we can certainly have a discussion then.

> So, my question is, in terms of resources, what would be the better choice for such medium sized but low on CPU and RAM groups? Is it ART or TreeKEM? 

(The above should not be construed as a request to not explore the
answers to these questions.)

-Ben