Massively Parallel Identification of Privacy-Preserving Vehicle RFID Tags

This article proposes a massively parallel identification scheme of vehicle RFID tags. These tags use a pseudo-random identifier, which is the output of a hash function fed by a fixed secret key that uniquely identifies the tag and by two random challenges that change on each tag activation. The use of random challenges makes it extremely difficult for someone not knowing the secret key of a tag to track its multiple activations. For someone knowing all valid keys, finding out the key that generated a specific tag response requires a time-consuming exhaustive search, if the number of valid keys is large. This can be performed in a very efficient way on a general purpose graphics processing unit. Our simulations show that on a very demanding scenario a single Tesla S1070 system can identify in near real-time the tags generated by 100 single-lane highway RFID readers.