Re: [TLS] [Cfrg] 3DES diediedie

Philip Levis <> Wed, 07 September 2016 00:32 UTC

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Date: Tue, 06 Sep 2016 17:32:02 -0700
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To: Dave Garrett <>
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Cc: Derek Atkins <>,,, Hilarie Orman <>
Subject: Re: [TLS] [Cfrg] 3DES diediedie
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The market is moving to ARM Cortex Ms, in part because of their clean I/O architecture and good SoC support. An M0 with integrated BLE chipset is easily <1$ today at small scale. Extrapolate a few years and to volume of millions between large companies rather than small startups.  Software like mBed OS and 6lowpan support helps too. 

You or I might not want chips in our light bulbs, but some people will, and so it is part of the Internet landscape we need to keep in mind. 

Phil [sent from a phone]

> On Sep 6, 2016, at 5:17 PM, Dave Garrett <> wrote:
>> On Tuesday, September 06, 2016 04:40:30 pm Derek Atkins wrote:
>> Ben Laurie <> writes:
>>>    An ARM is far too much hardware to throw at "read sensor/munge data/send
>>>    data".
>>> The question is not "how much hardware?" but "price?" - with  ARMs including h
>>> /w AES coming in at $2 for a single unit, its hard to explain why you\d want
>>> to use a less powerful CPU...
>> Because this is a light bulb that sells for $6-10.  Adding $2 to the price
>> is just completely unreasonable.  The price point needs to be pennies.
>> Note that this is just one example, but yes, these level of products are
>> getting "smarter" and we, as security professionals, should encourage
>> "as strong security as possble" without getting the manufacturers to
>> just say "sorry, too expensive, I'll go without."  (which is,
>> unfortunately, exactly what's been happening)
> Personally, I'd just say "stop putting chips in light bulbs", instead. Companies making these things are unfortunately just not going to be making good security decisions. Bad or no security is cheaper than competent security, and selling light bulbs with bad security is not illegal. We'll be more successful focusing our effort on dealing with light bulb botnets than trying to get people to make secure "smart" light bulbs. There is no good solution on our end, and debating the price of chips for light bulbs is not a good way to make security decisions in TLS.
> Dave
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