[Cryptography] Smart electricity meters can be dangerously insecure, warns expert

[Arnold Reinhold]

> On Jan 2, 2017, at 11:37 PM, Peter Gutmann <pgut001 at cs.auckland.ac.nz> wrote:
> 
> Arnold Reinhold <agr at me.com> writes:
> 
>> But we know from the links you supplied previously that companies with
>> serious technical competence, like BT, are eager to supply this market. 
> 
> They're just eager to make money.  Both examples I gave were meant to
> illustrate how totally unrealistic the "solutions" that vendors were
> presenting to power companies were.  And while I would trust BT to provide
> internet and phone service, I sure wouldn't use them to run a smart-meter PKI.
> In fact a PKI is about the last thing I'd use for smart meters ("and now you
> have two problems").  For ready-made off-the-shelf solutions, LoRa would be a
> pretty good start in that area.
> 
> Peter.

Of course they are eager to make money. That’s not evil per-say. I presume large power utilities know how to run competitive procurements for sophisticated technology. Whether they have the skills on board or on tap to evaluate proposed security solutions is another question. I give them a better shot than large retailers, but it’s a concern. 

That said, it’s not clear to me that the PKI proposals are necessarily bad. This is a much simpler problem than the Internet PKI with its hundreds of independent CAs that are each trusted by default. The utility can be its own root CA and can exercise complete control of any second level CAs. Maybe there are simpler solutions. If so I’d expect some firm to bid one. 

I was not familiar with LoRa, but I found this white paper:

 https://labs.mwrinfosecurity.com/assets/BlogFiles/mwri-LoRa-security-guide-1.2-2016-03-22.pdf 

Putting aside long term problems with the fixed symmetric keys it uses, I notice that the LoRa physical layer depends on gateway transceivers "able to transmit over several kilometers.” That means the utility will have to acquire spectrum, assuming it doesn’t want to share the ISM band, and would have to place, connect and maintain dozens of Gateways throughout a city to get total coverage. A solution that uses the existing cellphone network might be more attractive to the utility as the only devices needed to be installed and maintained in the field would be the smart meters themselves. I expect a large utility is competent to make these tradeoffs, if they have access to people with good cryptographic judgement. There’s the rub, in my opinion. Cryptographic standards are set in too many places, with government security agencies having mixed agendas. Perhaps the world needs a Cryptographers' Cabal to provide independent judgement.

Arnold Reinhold