By Mary Catherine O'Connor
Sept. 18, 2009—Morgan Hill, Calif.
RFID hardware manufacturer
Alien Technology has announced a new security application designed to make RFID tags made with its Higgs 3
chip impossible to clone. The feature, known as Dynamic
Authentication, relies on a challenge/response algorithm to verify that a tag is authentic, explains Victor Vega, Alien's marketing director.
Alien began producing the Higgs 3 chip in April 2008 (see
Alien Technology Announces New EPC Gen 2 Chip), and while the chip has had the dynamic authentication capability since then, the company is now making available the
reader software needed to unlock the functionality. "We designed the Higgs 3 chip with layered security features," Vega says. The firm's intention was to make the features available in a staggered manner. "Rather than add all the security features to the chip at once, we layered them. The idea is that when it comes to security, we always want to stay one step ahead [of the fraudsters]."
The algorithm is a custom command that verifies the authenticity of a Higgs 3
EPC Gen 2 UHF passive tag by querying the chip. It is referred to as a dynamic authentication, because in response to a query from the
interrogator, the chip will change select different bits within its response each time it is verified. Only an authentic Higgs 3 chip will respond to the query this way, Vega explains. End users who have tags with Higgs 3 chips—even if those tags are already encoded and deployed in, say, a closed-loop asset-tracking application—can begin using the custom command by requesting a special application
protocol interface (
API) from Alien. Today, that API is available only for Alien's EPC Gen 2 RFID readers, but Vega says Alien will share that API work with other EPC Gen 2 reader manufacturers so that end users can deploy the command on those devices.
According to Vega, the dynamic authentication is the most robust custom command for the Higgs 3 chip, building on the already-available Higgs 3 security. These include the use of a 96-bit
tag identification number (TID) that is factory-programmed into the chip when it is fabricated. This number consists of 32 bits of data indicating the chip's maker and model (as required by the Gen 2 standard), and 64 bits for a unique ID number.
Alien Technology is not the first EPC Gen 2 chipmaker to program unique chip IDs—designed to be used in combination with an EPC or another unique number that the end user encodes to the tag
memory in order to authenticate a tag—into its products. But the Higgs 3, Vega says, is the first Gen 2 chip to use a 96-bit TID containing a 64-bit unique ID number (other makers have utilized up to 32 bits for this identifier).