Re: [Discuss-gnuradio] Car alarms and garage door openers

[Daniel O'Connor]

On Tuesday 06 June 2006 05:59, Matt Ettus wrote:
> After the Wired article today, I've received a couple of email from
> people who are concerned that the USRP could be used to clone their
> keyfob transmitters for car alarms and garage doors.  I'm not concerned,
> since there are already many ways to do this (just check the back of
> pupular science magazine).  However, I am curious about it.  I know that
> we can capture and play back any rf signal.  The question is whether
> that replayed signal would result in the door being unlocked.  I was
> under the impression that most of those systems allow an unlock code to
> only be used once, but does anyone out there know for sure?

"It depends"
Some car systems are pretty sophisticated and cycle through codes to prevent 
replay attacks.

AFAIK most garage door openers are pretty simple, although I guess it would be 
fairly easy to check by listening to one and seeing what, if anything, 
changes from press to press.

Microchip make a tx/rx pair that has funky crypto (although I haven't looked 
at how good it really is).

Don't forget dorbells! I have a 433MHz wireless doorbell which could be cloned 
8-)

-- 
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
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