Is Remote Keyless Entry Any Safer Than It Used to Be?

Clue4All asks: "The time has come for me to start looking for a new car to buy after the winter snows have come and gone. Every car I'm interested in seems to come standard with Remote Keyless Entry with all their models. Has this technology become safer since I last bought a car? I remember seeing a news story years ago about burglars receiving signals used to open garage doors, and Google turned up articles like this from a few years ago. Apparently, some keyless entry systems now use "code hopping," which changes the signal after each use, making copying the signals pretty hard. I've requested information from a few car companies as to whether they employ such technology, what are your findings? Are these safe? I ask because I live in an apartment complex, not that I'd worry about anyone living around me doing something like this, but the thought is still there."

Comments

Security through obscurity

[Sherloqq]

Although I usually do not recommend this approach, consider obtaining security through obscurity.

Factory-installed keyless entry / remote starter systems all come from the same company, so if you get a Dodge Intrepid with an installed system, it will be identical to every other Dodge Intrepid's system. If you're afraid of someone scanning the remote's codes to gain access to your car, consider getting an aftermarket system. They're abundant in today's DYI market, and every automotive store carries a few different brands. Most of them are likely to have varying circuitry, varying frequencies, varying communication protocols, which make it that much harder and impractical for a would-be thief to get a scanner for (instead, get a scanner that caters to a wider "audience", if you will).

Naturally, a thief bent on stealing your car might get frustrated with not being able to crack your remote's code, perhaps to the point of using a jimmy and scratching the precious paint job, or even using a blunt object and simply breaking the glass. But at least your car will still be there :)

Personally, I use a remote system from ICDynamics. It gives me remote start, keyless entry and trunk release options, and that's good enough for me. Gets good range, too (over 300ft), so I can start my car up from the comfort of my home on days like today (a few degrees below freezing).

No, I do not work for them :) I'm just a happy customer.

Re:Multiple Remotes?

[Matt_Bennett]

What if you have multiple remotes?

I read some technical literature on code-hopping remotes- you can have multiple remotes and so forth. A code hopping remote is a one-way device- it only transmits, and it transmits a different code each time you press the button. The reciever knows what the code was the last time you pressed the button, so it knows what the next code should be (they use very, very long pseudo-random sequences).

So what happens if you press the remote when you're too far away, or your 3 year old finds it in the car and presses it merrily for a few miles until he gets bored? If the current code is code N, the next to be transmitted is code N+1, and the next that the reciever will key on will be N+1 to some range of N+X where X is pretty large, but still far smaller than Y, the total number of different codes.

In addition to keying on something in the next group of X codes, another safeguard thats used is to key on two successive remote-keys- lets say my transmitter is out of sequence, say by A - the reciever is looking for a code between N+1 and N+X- it recieves the code N+A (where N+1N+AN+X) It won't key on that, but if the next code it recieves is N+A+1, it knows that it got the right sequence, and will only open after the next keypress.

For multiple remotes, it adds a separate domain to key upon(say, Y to Y+N)- slightly less secure, but of course the more keys there are for any door, the less secure it is.