RF Activation Seeks to Turn off Theft

By Mary Catherine O'Connor

June 21, 2006—A startup in Emeryville, Calif., has developed an RFID-based technology designed to prevent the theft of DVDs and other types of optical media by using an RFID tag to disable the media until the point of sale, where the media can then be enabled for use. "The system is based on the idea that thieves don't want things that don't work," explains Frank LoVerme, senior vice president of Kestrel Wireless. Kestrel developed the technology and will be working with a DVD manufacturer and a retailer to conduct a pilot test of the system early next year. The company has dubbed the technology radio frequency activation, or RFA.

The UHF tag is attached to the media and linked to an optical shutter made of electrochromic film, a material that changes color when electrical voltage is applied to it. The film, one-fiftieth the thickness of a human hair, can be set to a darkened state by conveying a charge through the tag. Once the film has been darkened, a DVD player's laser is unable to access the disc's startup files, making it unplayable.

Kestrel describes the passive UHF RFID tag attached to the media as "an EPC Class 1 Gen 2 tag with extensions," meaning it meets all Gen 2 air interface specifications, but also has extra memory and output ports to support the optical switch activation/deactivation protocol, as well as the charge needed to toggle the optical film between its darkened and clear states. This protocol supports data encryption, protecting the disc from being activated by an interrogator without access to the encryption keys, stored on a secure Kestrel database.

Using the System in the Retail Supply Chain
According to Kestrel, before leaving the manufacturing facility, the film and tag are attached to each disc—the tag's antenna encircles the plastic ring at the center of the disc—and the film is darkened. An EPC and encrypted keys are encoded to the chip's memory, and a warning sticker is applied to each packaged disc, alerting would-be thieves that it will not function until it is activated at the point of sale. At the retail site, a clerk uses an RFID interrogator to read the tag embedded in the disc. The interrogator sends EPC data from the tag to the POS system, which adds the product to the list of items being purchased. Once the purchase is completed, the POS system sends the encrypted activation key stored on the tag to the Kestrel database, which forwards it on to the interrogator. The clerk can then interrogate the disc a second time to activate it.