RFID Drivers' Licenses Debated

meganthom writes "How would you feel about having an RFID chip in your driver's license? Virginia is considering just such a measure, largely because several of the 9/11 hijackers were licensed there. Civil rights advocates are obviously unhappy with this turn of events, and it seems the ACLU has already taken the case. Proponents claim it would help law enforcement determine that you are who you claim to be and would make forgeries less common. The Federal government is also considering uniform 'smart card' standards."

Comments

Re:Oh great...

[Dr Reducto]

Just pop your license in the microwave. I think that kills RFID.

Even easier

[Engineer-Poet]

Laminate some aluminum foil to card stock with spray glue. Fold in half. Keep your RFID cards inside unless they're in use; the pair of ground planes will make it effectively impossible to get signal to or from the cards. If you want to be able to flash your card/DL without allowing it to be read without extreme difficulty, put foil on one side of a clear envelope or card holder and keep the card inside.

Another thing to do would be to make a reader-detector, to see who is trying to scan your cards surreptitiously. That would be a great way to embarass people and businesses trying to play Big Brother, and you might even be able to get such snooping prohibited by law.

Re:I'm Born 'n' Bred Virginian

[aardwolf204]

Who modded this funny? Maybe it was the tin foil keyword filter. I'm a Virginian thats seriously thinking about moving way up north if things get much worse.

Re:Read distance depends on the reader

[dgatwood]

A lot depends on the antenna (i.e. the RFID itself) not just the reader.

Not really. To a limited extent, yes, but not as much as you might expect.

I use what I suspect are the same key cards that the grandparent (great grandparent?) poster uses at work. Most of the readers require nearly physical contact. The ones on the garage downstairs, however, to avoid people having to get out of their car, can read those same badges from... I believe 24 inches, if memory serves. Basically, as soon as I get my badge near the car window, it beeps.

The device is passive. It reacts to an RF (or in the case of most badges, magnetic) signal by modulating that signal and bouncing it back. The range, AFAIK, is limited mainly by the transmission power of the reader. Granted, there are other issues, like the ability to get something resembling line-of-sight to the RFID tag (i.e. curvature of the Earth limits), the ability to distinguish between a potentially large number of RFID tags within that range, and multipath distortion problems, but those still won't prevent a range of several feet under most conditions.

There's probably also some fairly high power limit beyond which you would smoke the card if you got too close to the reader, but if you lower that limit enough on your cards to force all RFID readers to only work in close proximity, odds are the devices would have a high failure rate just from "natural" phenomena... like standing too close to your microwave or even walking outside on a day when you can see the aurora borealis.

Grounding is not required

[Engineer-Poet]

A faraday cage has to be grounded. A piece of aluminum foil in a cloth pocket is not.

Wrong. A Faraday cage does not have to be grounded to isolate anything inside, any more than a dipole antenna has to be grounded to radiate. What the foil surfaces would provide is a pair of "image planes" which suppress currents in anything nearby; a pair of them spaced closely is going to provide a very large amount of attenuation.

If you want an example of this, cut out a small piece of aluminum foil, one inch by four or so. Tune a hand-held AM radio to a strong station. Now put the foil over the housing near the loopstick antenna; the reception will die. Doesn't take much, does it?