Information confinement, privacy, and security in RFID systems

This paper describes an identification and authentication protocol for RFID tags with two contributions aiming at enhancing the security and privacy of RFID based systems. First, we assume that some of the servers storing the information related to the tags can be compromised. In order to protect the tags from potentially malicious servers, we devise a technique that makes RFID identification server-dependent, providing a different unique secret key shared by each pair of tag and server. The proposed solution requires the tag to store only a single secret key, regardless of the number of servers, thus fitting the constraints on tag's memory. Second, we provide a probabilistic tag identification scheme that requires the server to perform simple bitwise operations, thus speeding up the identification process. The proposed tag identification protocol assures privacy, mutual authentication and resilience to both DoS and replay attacks. Finally, each of the two schemes described in this paper can be independently implemented to enhance the security of existing RFID protocols.