MIT researchers have developed an anti-tampering ID tag that provides improved security compared to traditional radio frequency ID (RFID) tags that are commonly used for authentication.
The new tag, which is smaller, cheaper, and more secure than RFIDs, uses terahertz (THz) waves for authentication. However, like traditional RFIDs, it faced a vulnerability where counterfeiters could peel the tag off an authentic item and attach it to a fake one.
To overcome this flaw, researchers mixed small metal particles into the glue used to stick the tag to the product. When THz waves are shone on the tag, they reflect differently based on the orientation, size, and location of these particles, creating a unique pattern akin to a fingerprint.
Counterfeiters could potentially destroy this pattern by peeling off and reattaching the tag. The design includes multiple slots so waves can hit different points on the object’s surface, capturing more information on the random distribution of the particles.
A vendor would take an initial reading of the anti-tampering tag once it was stuck to an item, storing these data for later verification. Furthermore, a machine-learning model has been demonstrated to have at least a 99% accuracy in identifying similar glue-pattern fingerprints.
Despite its many benefits, the new technology is not without its limitations. For instance, due to high levels of loss during transmission, the THz wave sensor needs to be about four centimeters from the tag to get an accurate reading.
Additionally, researchers found that if the angle between the sensor and tag is over 10 degrees, the THz signal will degrade too much. The team plans to address these shortcomings in future work, with the hope of inspiring other researchers of the potential applications of THz waves.
The research, partly supported by the U.S. National Science Foundation and the Korea Foundation for Advanced Studies, was conducted by a team led by Eunseok Lee, an electrical engineering and computer science graduate student. The paper will be presented at the IEEE Solid State Circuits Conference.
