Re: [Cfrg] 3DES diediedie

Ilari Liusvaara <ilariliusvaara@welho.com> Mon, 29 August 2016 13:39 UTC

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Date: Mon, 29 Aug 2016 16:38:49 +0300
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: "David McGrew (mcgrew)" <mcgrew@cisco.com>
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Subject: Re: [Cfrg] 3DES diediedie
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On Mon, Aug 29, 2016 at 12:44:42PM +0000, David McGrew (mcgrew) wrote:
> 
> The malleability of the term IoT is causing trouble here.   Slide 6
> of Daniel’s talk is quite revealing.  To my thinking, by definition
> IoT devices are connected to the Internet in some way.

Yes, the variability of capabilities of IoT devices is extreme. From
devices that just barely can run some cipher gated to PSK, to ones
that can easily run TLS without any hacks to save resources.

There is no way to make TLS realistically work for the first kind,
since just the flexibility of TLS would impose unreasonable burden,
even if profiled down.

If one limits oneself to the low end, I would think that anything
that can realistically handle any profile of TLS can probably handle
a real symmetric cipher (>=128 blocks, >=128 bit keys).


-Ilari