Secure yoking proof protocol for RFID systems

In this paper, we propose a secure yoking proof protocol for RFID passive tags based on Zero Knowledge. The protocols that have been proposed earlier are either found to be vulnerable to certain attacks or do not comply with EPC standard for passive tags because they use complex encryption schemes. Also, the unique design requirements of yoking/grouping proofs have not been fully addressed by many. Our protocol addresses these important security and design gaps in yoking proofs. The proposed protocol uses pseudo random squares and quadratic residuosity to realize the zero knowledge property. Tag operations are limited to functions such as modulo (MOD), exclusive-or (XOR) and 128-bit Pseudo Random Number Generators (PRNG). Passive tags are capable of these operations and hence the protocol achieves EPC compliance and also meets the necessary security requirements.