Bolt works locally over Bluetooth with no Internet connection. The optional extra thing (Bridge) is if you would like to enable Internet connectivity. A $15 do

Bolt works locally over Bluetooth with no Internet connection. The optional extra thing (Bridge) is if you would like to enable Internet connectivity. A $15 dollar SDR wouldn't do it either. Most electronic locks aren't susceptible to replay attacks unless they're using KeeLoq and it's out of range. You might be able to do another kind of attack with three Ubertooth One's though. We got something like this working in our lab and I talked about it at DefCon 21 in the Wireless Village track - the basic patch is to use corroborate with other data (geo, time, etc.)