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

[Jonathan Thornburg]

> Jerry Leichter <leichter at lrw.com> asked:
> 
> Do smart meters have a remote shutdown capability?  I don't know. 

On Sun, Jan 01, 2017 at 04:51:42PM +0000, Peter Gutmann wrote:
> No.  They're built to be as cheap, compact, and low-power as possible.  All
> they are is a minimal switchmode power supply powering an SoC with some power
> sensing capabilities and a radio modem.  Adding heavy-duty power control
> circuitry capable of switching, potentially, three-phase power, or at the
> least several tens of amps (so thousands of kVA) of single-phase power, isn't
> going to happen.

It's usually a lot more than "several tens of amps".  A single circuit
is typically 15 amps in Canada/USA, and a house may have 10 to 20 of these.
My home in Canada (built/wired in the 1980s) has a 200-amp service entrance.
Power-switching for that would require some hefty hardware.

-- 
-- Jonathan Thornburg <jthorn at astro.indiana.edu>
   Dept of Astronomy & IUCSS, Indiana University, Bloomington, Indiana, USA
   "There was of course no way of knowing whether you were being watched
    at any given moment.  How often, or on what system, the Thought Police
    plugged in on any individual wire was guesswork.  It was even conceivable
    that they watched everybody all the time."  -- George Orwell, "1984"