An authentication protocol for secure tag-reader communication

RFID (Radio Frequency IDentiflcation) is recently becoming popular, and plays an important role in ubiquitous society due to its deploying convenience and economic efficiency. Furthermore, RFID nowadays comes into the spotlight as a technology to substitute the barcode system. RFID technology, on the other hand, is jeopardized from various attacks and problems preventing widespread RFID deployment. We focus ourselves on designing a secure and efficient protocol for authentication between tag and reader in a RFID system. There must be a tradeoff between scalability and untraceability. However, we try to keep the constant computational time in back-end server regardless of the number of tags when designing an untraceable protocol.