Researchers at MIT have developed a cryptographic ID tag that is significantly smaller, cheaper, and more secure than traditional radio frequency identification (RFID) tags. The new tag is based on the use of terahertz waves which are smaller and have much higher frequencies than radio waves.
The innovation overcomes a major security flaw common with RFIDs where a counterfeiter could remove the tag from an authentic item and reattach it to a fake one. The new anti-tampering tag counters this risk by incorporating microscopic metal particles in the adhesive used to attach the ID to an object. When terahertz waves are shone on the tag, they reflect a unique pattern back, akin to a fingerprint. If the tag is removed and reattached, the unique reflective pattern is destroyed, alerting security systems to potential counterfeiting.
Machine learning is used to detect tampering by identifying this unique fingerprint with an accuracy of over 99%.
Unlike traditional RFIDs which may be too large for some applications, the new antitampering tag is only 4 square millimeters in size, meaning it can be applied to much smaller items, including certain medical devices. Furthermore, the tag is cheap to produce, making it viable for widespread use throughout supply chains.
To verify an item, an initial reading of the tag is taken once it is attached to an item, and that data is stored in the cloud to be used later for verification.
However, the technology has its limitations. The recordable range of terahertz waves is only about 4 centimeters, meaning the sensor that authenticates the tag must be very close to it. In addition, the angle between the sensor and the tag must be less than 10 degrees or the terahertz signal will degrade too much. Despite these challenges, the researchers are optimistic about the potential of terahertz waves in ID, security, and authentication solutions.
The research was partly funded by the U.S. National Science Foundation and the Korea Foundation for Advanced Studies. The researchers plan to continue their work to overcome the limitations of the technology and are hopeful that the success of their project will inspire further innovations in the use of terahertz waves.
