An Enhanced Synchronization Approach for RFID private authentication

Radio frequency identification (RFID) technologies are on their highway to pervasive usage. However privacy protection is still an important problem since RFID tags attached to items are so cost constrained. Privacy preserving authentication approaches are proposed to authenticate tags without private information leaking. Previously designed approaches based on synchronization seeks O(1) complexity. While these synchronization based methods are efficient in normal case, they have weak points when desynchronized. When maliciously scanned, information stored in tag and reader goes farther and farther away from each other. An adversary can utilize this point to track a tag. We propose an enhanced synchronization approach for RFID private authentication, ESP, to solve this problem. ESP can eliminate the problem caused by desynchronization attack and help detecting replay attack. Analysis shows that ESP enhances privacy protection while still maintaining the authentication efficiency.