FastRIPP: RFID Privacy Preserving protocol with Forward Secrecy and Fast Resynchronization.

In the next future Radio Frequency IDentification (RFID) systems will be so pervasive that everyone will wear (maybe unawares) a kit of personal tags. However, a major con- cern that prevents a wide diffusion of this emerging technology is privacy. Several proposed protocols try to solve the privacy issue, but are exposed to many others security flaws, such as denial of service or lack of forward secrecy. One recently proposed solution addressing all these problems is RIPP-FS: an RFID identification protocol that guarantees privacy, authentication and forward secrecy, allowing the reading of many tags at once. While efficient, RIPP-FS requires some extra computations on the tag side when a tag misses several consecutive queries from the reader. In this paper we propose FastRIPP, an efficient protocol that significantly reduces the exposed overhead. This improvement is inspired by an efficient hash traversal amortization technique that uses fractal hash sequence representation. We analyzed the performances of the proposed protocol compared with the original version of RIPP-FS. The results of extensive simulations confirm the gain of performance of the proposed protocol. Finally, note that the proposed solution could be adopted by other RFID identification protocols as well.