Privacy-preserving authentication with low computational overhead for RFID systems

Providing secure authentication in a resource limited Radio Frequency Identification (RFID) system is a challenging task. To address this problem, we propose a High-Performance RFID authentication protocol, HPA, based on AVL tree which is a highly balanced binary search tree. In the protocol, each tag of a RFID system is associated to a node on an AVL tree. It shares a unique secret key with the database and each key is stored in a node on the tree. Compared with existing RFID schemes, HPA has two salient features: logarithmic complexity of searching a node and identifying a tag; much lower computational overhead and storage cost. Simultaneously, HPA is secure enough to defend against both passive and active attacks.