3.1 Design goal

Our design goals are set to achieve as follows:

• Defending against impersonation activities:
  It is required to be computationally impossible for the adversary, such as eavesdropper, malicious inside attacker, or malicious owner of RFID reader, to impersonate a smart tag that has not been compromised. In addition, if a smart tag has been reported loss or stolen, the stolen tag should be revoked such that the adversary should not be able to use this stolen tag to impersonate the identity of original owner to gain access.
• Strong Authentication
  Even when the RFID readers verify the legitimacy of smart tags, the identity of smart tags should remain anonymous during any communication transmission involved with the tag.
• Low-resource Consumption
  The proposed scheme has low computational, communication and storage overheads.