A motion sensor in the remote could mitigate the issue and maintain convenience.
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Thieves boosting signal from key fobs inside homes to steal vehicles
121–130 of 449 posts
Re: Thieves boosting signal from key fobs inside homes to steal vehicles
#122A motion sensor in the remote could mitigate the issue and maintain convenience.
How battery intensive are accelerometers? The last fob I had required a battery change once every year or so already, increasing that frequency could be quite annoying. And I'd rather not have yet another device I need to regularly charge.
Re: Thieves boosting signal from key fobs inside homes to steal vehicles
#123A good solution to that problem are UWB radios with timestamping (like the Decawave DW1000), which let you measure the time it takes for the signal to travel. You can then place physical limits on the proximity, rather than assuming that a strong radio signal means proximity.
Coupled with a cryptographic authentication protocol these solve the issue quite nicely.
Re: Thieves boosting signal from key fobs inside homes to steal vehicles
#124I already put mine in a metalic bag for the night, or just press the "lock" button twice which disables the keyless entry system entirely. Manufacturers really need to hurry up and implement more accurate timing detection in the keys - it should be absolutely trivial to detect how far away the key is based on the response time, but for some reason manufacturers don't do this yet. Edit: I also know people who take the…
« it should be absolutely trivial to detect how far away the key is based on the response time » It's not possible. A keyfob has a relatively slow R/F communication channel, less than 1 Mbit/s (at best) because it's constrained by power. Thus the "length" of a bit transmitted over the air is 300 meters or more. The receiver needs to demodulate "300 meters" of R/F signal to recover a single bit. A difference of +/- 10…
It is absolutely possible. As I wrote elsewhere in the comments, you need to use radios with timestamping that can measure the distance (10cm accuracy is achievable). See for example Decawave DW1000 radios.
Use those and you can base your distance estimation on time measurement, rather than signal strength. Amplifiers won't help.
Re: Thieves boosting signal from key fobs inside homes to steal vehicles
#125Earlier quoted context omitted.
Since most car manufacturers seem to be vulnerable (to my knowledge), I assume all or most buy the same COTS keyfob + electronic lock product. Much like Takata airbags or Bosch ECUs. Being a step away from the problem probably helps keep that OEM manufacturer from strapping in and solving it. They don't feel any pain from it.
The vulnerability is pretty much inherent to the idea. No amount of encryption can protect you from a relay attack. The only foolproof mitigation is to enforce a short round trip time to ensure the fob is actually close to the car, but with the short distances involved that means the fob has to generate and transmit a response within a few nanoseconds.
Can't you stop the car if the key is not present in the car? I guess the thieves could fake it with long distance transmission of the signal, but that would be more difficult and the further the car drives away from the actual key, the easier if becomes to detect the timing delay.
Re: Thieves boosting signal from key fobs inside homes to steal vehicles
#126Earlier quoted context omitted.
Insurance companies pressure drivers who have these misfeatures, drivers pressure car manufactures. See also: discounts for anti-theft tech and airbags.
The latest insurance "incentive" is a tracking device in your car that tracks when and where you drive, how fast, how hard you corner and stop, etc. I've declined this but expect that insurers will push for it to become mandatory. They would love to be able to charge unsafe drivers more money, and in the abstract I don't have a problem with that, but the tracking is creepy.
No no no, they would love to charge everyone more until they prove to be safe drivers — ready to withdraw the discount at the first doubt.
This is why I am not going to get one, nor a “smart” water or electricity meter: give more data to corporations, and you can be sure that they will use it against you.
Re: Thieves boosting signal from key fobs inside homes to steal vehicles
#127It seems to me like there is often just as much creativity in thievery as there is in entrepreneurship.
It is astonishing the lengths some people will go to not earn a honest salary.
Re: Thieves boosting signal from key fobs inside homes to steal vehicles
#128Earlier quoted context omitted.
So if you accidentally drop your keys while entering, or your passenger departs with your key, the car should lock itself 2 minutes later while you are driving?
Yeah, sounds reasonable to me. Either of those situations should already be solved. My car at least yells if the key goes away when the car is on and if you’re dumb enough to keep driving and that’s kinda on you.
No, it is not reasonable for the car to stop suddenly without the key. Even if it stops by going into an emergency limp mode, this could seriously endanger the occupants by leaving them in a dangerous traffic situation, a dangerous location, or with other issues.
This is why every car company has examined it and chosen to not do it.
This feature actually saved huge inconvenience for us once. While visiting the other coast for wife's mom in the hospital, we used one of her parent's cars to drive to the airport with her brother to drive it back. We get out at the airport, get luggage, hugs, bye, head into terminal -- with the key still in her purse. Car running, doesn't notify him until too late to chase. If it stopped after 2min, he'd be stuck somewhere outside an airport 100mi away from anyone he knew. Instead, he just drove it home, got & used the other key for a few days, and we mailed back the first key when we arrived.
Things that seem reasonable at first....
Re: Thieves boosting signal from key fobs inside homes to steal vehicles
#129ive tested a couple of things to see if they would block the signal by putting the keys in the container and then standing next to the car and trying to open the door
kids Lunch box would not block, small metal garbage can, would not block, cookie tin would not block. All would block if you lined the edge with aluminum foil before putting the top on.
foil lined Potato chip bag would block.
Wrapping in enough aluminum foil will block the signal
Those faraday bags are convenient, but I park in the garage so Im not that worried. Garage door openers now have lock switches which prevent the door from being opened using any opener.
Re: Thieves boosting signal from key fobs inside homes to steal vehicles
#130ive tested a couple of things to see if they would block the signal by putting the keys in the container and then standing next to the car and trying to open the door kids Lunch box would not block, small metal garbage can, would not block, cookie tin would not block. All would block if you lined the edge with aluminum foil before putting the top on. foil lined Potato chip bag would block. Wrapping in enough aluminum…
"Garage door openers now have lock switches which prevent the door from being opened using any opener."
More info on this? Mine is older and doesn't have anything like it.