MIT Researchers Build Tiny Tamper-Proof ID Tag Utilizing Terahertz Waves

A few years ago, MIT researchers invented a cryptographic ID tag - but like traditional RFID tags, "a counterfeiter could peel the tag off a genuine item and reattach it to a fake," writes MIT News. "The researchers have now surmounted this security vulnerability by leveraging terahertz waves to develop an antitampering ID tag that still offers the benefits of being tiny, cheap, and secure."They mix microscopic metal particles into the glue that sticks the tag to an object, and then use terahertz waves to detect the unique pattern those particles form on the item's surface. Akin to a fingerprint, this random glue pattern is used to authenticate the item, explains Eunseok Lee, an electrical engineering and computer science (EECS) graduate student and lead author of a paper on the antitampering tag. "These metal particles are essentially like mirrors for terahertz waves. If I spread a bunch of mirror pieces onto a surface and then shine light on that, depending on the orientation, size, and location of those mirrors, I would get a different reflected pattern. But if you peel the chip off and reattach it, you destroy that pattern," adds Ruonan Han, an associate professor in EECS, who leads the Terahertz Integrated Electronics Group in the Research Laboratory of Electronics. The researchers produced a light-powered antitampering tag that is about 4 square millimeters in size. They also demonstrated a machine-learning model that helps detect tampering by identifying similar glue pattern fingerprints with more than 99 percent accuracy. Because the terahertz tag is so cheap to produce, it could be implemented throughout a massive supply chain. And its tiny size enables the tag to attach to items too small for traditional RFIDs, such as certain medical devices... "These responses are impossible to duplicate, as long as the glue interface is destroyed by a counterfeiter," Han says. A vendor would take an initial reading of the antitampering tag once it was stuck onto an item, and then store those data in the cloud, using them later for verification." Seems like the only way to thwart that would be carving out the part of the surface where the tag was affixed - and then pasting the tag, glue, and what it adheres to all together onto some other surface. But more importantly, Han says they'd wanted to demonstrate "that the application of the terahertz spectrum can go well beyond broadband wireless." In this case, you can use terahertz for ID, security, and authentication. There are a lot of possibilities out there."

Read more of this story at Slashdot.