Speaking to a packed and sweaty crowd this afternoon, RFID researcher Melanie Rieback explained the technology behind RFID Guardian, a personal firewall she’s developing that will protect your privacy in an world where your clothes, library books, and passport contain RFID tags. You can see the latest completed version of the Guardian above — it’s an ordinary circuitboard with two antennae and powerful onboard processors. It intercepts signals from RFID readers that are attempting to get information from, say, the RFID in your passport. Like a software firewall, it won’t let those signals reach your RFID unless you want them to — for example, if you’re passing through customs.

“You can set the Guardian to selectively block your RFIDs,” Rieback explained. So if you don’t want anybody snooping on the RFID in your credit card, but you don’t mind if they read the one in your Nikes, you can use the Guardian to stop only signals that query your credit card. This device should prove a boon to privacy advocates who fear that people will be tracked everywhere when RFIDs become ubiquitous in most consumer items, key cards, and IDs.


Right now the Guardian is a prototype, but Rieback’s working on compact version that will be available commercially in six months to a year for about 100 Euro. Simply clip the Guardian to your belt, and you can set it up to prevent people from reading your RFID tags and snarfing your personal data. As she fielded questions from the audience after her lecture (see right), Rieback explained the ins and outs of the chipset she’d chosen as well as why she’d become interested in this work. She wants to protect consumer privacy, as well as alert the RFID industry to some of the dangers that crop up when technology makes it easy for malicious individuals to make off with personal data or track a victim’s location.

In the future, Rieback predicted, the RFID Guardian could be something you download to your next generation smart phone. Think of it as a do-not-call list for RFIDs. — Annalee Newitz