Offline grouping proof protocol for RFID systems

Several grouping proof protocols have been proposed over the years but they are either found to be vulnerable to certain attacks or do not comply with EPC Class-1 Gen-2 (C1G2) standard because they use hash functions or other complex encryption schemes. Also, synchronization of keys, forward security, proving simultaneity, creating dependence, detecting illegitimate tags, eliminating unwanted tag processing and denial-of-proof (DoP) attacks have not been fully addressed by many. Our protocol addresses these important gaps and is based on Quadratic Residues property where the tags are only required to use XOR, 128-bit Pseudo Random Number Generators (PRNG) and Modulo (MOD) operations which can be easily implemented on low-cost passive tags and hence achieves EPC C1G2 compliance.