A few years ago, MIT researchers created an innovative cryptographic ID tag several times smaller and much cheaper than traditional RFIDs (radio frequency tags) commonly used to authenticate products. Despite the significant improvements in size, cost, and security this new ID tag brought, it shared a major security vulnerability with RFIDs, where a counterfeiter could remove the tag from a genuine product and attach it to a fake one, thus tricking the authentication system.
To overcome this hurdle, the team developed an antitampering ID tag using terahertz waves, which are smaller and have higher frequencies than radio waves. This new invention provides all the benefits of being small, cheap, and secure, with an added layer of protection against counterfeiting.
The researchers incorporated microscopic metal particles into the glue used to attach the tag to the product. These metal particles interact with terahertz waves to create a unique pattern on the product’s surface, similar to a fingerprint. This specific pattern is used to authenticate the item. If anyone tries to remove the tag and reattach it, the pattern is destroyed, providing a safeguard against tampering.
In addition to enhancing security, the team developed a machine learning model capable of accurately detecting tampering attempts, through identifying similar glue pattern fingerprints with over 99% accuracy. This innovative solution offers distinct benefits for supply chains due to the tag’s low production cost and small size, making it suitable for even the smallest products, such as certain medical devices.
Despite these advancements, the system does face some limitations. Terahertz waves experience significant transmission loss, meaning the sensor must be placed quite close to the tag (about 4 cm) to get an accurate reading. In addition, the angle between the sensor and the tag has to be less than 10 degrees to prevent significant signal degradation.
Moving forward, the research team plans to address these challenges and explore the further potential of terahertz waves. They believe these waves could offer expansive possibilities beyond broadband wireless, including ID validation, security, and authentication applications. The research was sponsored in part by the U.S. National Science Foundation and the Korea Foundation for Advanced Studies.
