US Patent 9489785 RFID secure authentication

Authentication systems and methods for a population of devices each associated with an RFID tag are described. For each device, a secret key is combined cryptographically with a publicly-readable unique identifier (UID) of an RFID tag to obtain a unique authorization signature. The RFID tag is prepared utilizing the unique authorization signature as memory-access and/or tag-operation password(s). The systems and methods may safeguard against attacks whereby compromise of a single tag will not compromise the entire population of devices and may reduce or eliminate the use of inappropriate surgical devices during a surgical procedure.