RFID Presentation

         imported      ic.ac.uk · Tech · Geek · RFID

For anyone interested, the slides for my RFID presentation are here.

RFID Basics!

         imported      ic.ac.uk · Tech · Geek · RFID

So, at the moment, I’m writing a presentation about the operation and the security implications of RFID. During the course of the random searches around the internet, I’ve found that there’s a lot of really, really cool work going with respect to RFID. Even more great than the output on the subject is who is studying it. Lots of really cool observations are coming out of the open source friendly community - some of the best presentations on the subject are from presentations at CCC. Along with projects like OpenPCD, this output is pretty cool!

However, that’s not really the point of this post. During the course of reading around, I’ve found that whilst there’s a lot of information around - there’s also a lot of FUD that surrounds that information. My presentation is trying to give people (with some physics background) a simple idea of what RFID is, and particularly how it works. Given that I’ve already done a quick summary of how RFID works, I figured I’d blog about it, so that I can add to the mush of material that you just can’t reference online.

I’ll discuss a high frequency system - since cards such as MIFARE (which e.g. Oyster uses) work at around 13.56MHz. The RFID system consists of two elements - the reader, and the tag. Tags come in a number shapes - active, passive, and semi-passive. Really, it’s the passive tags that I’m interested in. The image below shows the anatomy of a (simple) passive tag. It’s composed of an antenna - running around the card, an IC, and a substrate that they’re both attached to.