I had wondered about this before.

(basically tmps can be used to monitor more than your tire pressure)

http://www.hexview.com/sdp/node/44

 

LOL... trying to live off the grid huh!

RFID money.. from RFID blog.


Edit:
1. I think the thread need to be moved.
2. At this moment, TPMS signals used in automotive industry is considered very weak in strength. A part of my job is to play with a TPMS scanner. An very ez way to point out, a signal only can be detected fome the sensor sitting next to the scanner, but not the sensor in the next tire. LOL!

 

Everyone already has a unique ID in big bold letters attached to the outside of your car, the license plate bolted to your bumper! There are already systems that some agencies use that take pictures of cars and OCR the license plates and run the plates. Even if some nefarious person read some unique information off of your tpms it isn't giving anything more away really.
I agree the close proximity needed to read the id makes the risk almost zero. I suppose gas stations or other the drive through window at the in-N-out burger could use it to be annoying, instead of asking me for my order maybe they could figure out it was me and ask me if I wanted my usual, but again they could do the same by taking a picture of the license plate.
Also adding encryption to the tpms communication would also use up the teeny battery in the tpms that much faster and make them slightly more expensive to make.

 

Add encryption to do what? Encrypt the pressure data? That's not the problem. The unit ID can't be encrypted to make it impossible to uniquely identify the sender. This is no different than an IP header not being encrypted. Sure you can encrypt the contents of the packet, but the header info is and always must be clear text. If it isn't, then every router in the path needs to decrypt the header info with a key shared across the entire network.

Your TPMS is no different. The unique ID can't be encrypted in a way that prevents identification.

Sorry, it's a non-issue.

 

Yes encrypt the pressure data and any other data that tpms would be programmed to transmit in the future.

Yes everyone knows that a header can't be encrypted, but it's payload can. I only care about payload and not identifiers. LIke the reader above stated that my license plate does that already. But it doesn't transmit things like rate of speed/ gps/ etc (which i know tpms currently don't do that, but could be made to do that very easy.. yes they could put other devices on our car that do the same thing. Just thought the article brought up something interesting that i had thought about before.