On Tue, Oct 25, 2016 at 10:40:40PM -0700, Chuck Hast wrote:
> I have a "Wifi thermostat" from Honeywell, the drawback
> is you have to connect the thing to the cloud, for some
> reason the thermostat can reach the server ...

Your satellite connection is, in effect, up to a million
miles long.  Signals to the Honeywell server and back
travel through the satellite twice, up and down, and that
is half a second right there.  Then there is queueing time.
You share the limited satellite channel with thousands of
others simultaneously, and you wait your turn.  That can
add many seconds to the delays if the channel is congested.

I doubt that Honeywell's subcontracted Chinese engineers
even thought about delays through satellites when they
designed the timeout and retry response on your thermostat.
Even if the timeout was programmable, you probably need
to use the remotely managed GUI to change it.

I'd take it back, and avoid net-connected controllers 
until you get optical fiber.  But then, I would never
expose a life-and-death appliance (which furnaces can be)
to the internet.  A malicious cracker could dial up the
furnace to maximum temperature on a hot summer day, or
permanently disable it during freezing temperatures.

If the thermostat was more intimately involved in furnace
operation (like direct control of gas feed and ignition),
it could turn your house into a fuel-air bomb, like the
one that took down the Murrah building in OKC in 1995.
Someday, state-sponsored cyberterrorists may firebomb
whole cities with a few well-hidden exploits like that.

Keith

-- 
Keith Lofstrom          [email protected]
-----
Don't waste your vote in 2016!  Give it to the Republicans
and Democrats, and they will gladly waste it for you!
_______________________________________________
PLUG mailing list
[email protected]
http://lists.pdxlinux.org/mailman/listinfo/plug

Reply via email to