Scalable RFID security protocols supporting tag ownership transfer

We identify privacy, security and performance requirements for RFID protocols, as well as additional functional requirements such as tag ownership transfer. Many previously proposed protocols suffer from scalability issues because they require a linear search to identify or authenticate a tag. In support of scalability, some RFID protocols, however, only require constant time for tag identification, but, unfortunately, all previously proposed schemes of this type have serious shortcomings. We propose a novel scalable RFID authentication protocol based on the scheme presented in [1], that takes constant time to authenticate a tag. We also propose secret update protocols for tag ownership and authorisation transfer. The proposed protocols possess the privacy, security and performance properties and meet the requirements for secure ownership transfer identified here.