The security and privacy of RFID (Radio Frequency Identification) systems becomes an important subject especially for low cost RFID tags. A lot of authentication protocols were proposed to insure the security and in the same time meet the resource limitations. In this paper, we proposed an ultralight weight authentication approach based on permutation, XOR and rotation functions. As a result, the computational complexity and communication cost will be reduced as well as increase performance. Finally, our approach proves that the protocol is a lightweight, resistant to known attacks and has an effective security mechanism based on an analytical method.