Improved yoking proof protocols for preserving anonymity

In emerging RFID applications, the yoking proof provides a method not only to ensure the physical proximity of multiple objects but also to verify that a pair of RFID tags has been scanned simultaneously by a reader. Previous studies have focused on generating the yoking proof, but have not been successful in preserving the anonymity of tags. In this paper, we address two attacks on tracking RFID tags and propose a new yoking proof protocol to improve anonymity of the tags. For better practicality, we also present authenticated yoking proof generation against DoS attacks on the system. Our analysis shows that the proposed protocols achieves improved anonymity effectively. Specifically, the protocols require the least number of computational steps and modules in a tag, while preserving its anonymity.