There are varies of RFID authentication schemes have been proposed. Most of them address on privacy issues over the tag and the user, however, they are still vulnerable to different attacks and with some weaknesses. In addition, the readers and the back-end server are considered as a single entity for these typical RFID schemes, hence, the communication channel is assumed to be secure. Recently, a concept of mobile reader has been proposed in which the reader is possessed by the user and is equipped inside a mobile device.The mobile RFID reader possessor can extract the information about the tagged objects by communicating
with the back-end server through an insecure channel; consequently, a secure RFID authentication is needed.In this paper, two RFID authentication schemes are proposed for the reader-portable RFID environment.These schemes not only provide a novel usage of RFID system, but resolve privacy threats while a mobile reader is not authorized to acquire every tag’s information.