Dynamic Query Tree AntiCollision Protocol for RFID Systems Radio frequency identification (RFID) has been widely used in various areas, such as logistics, healthcare, manufacture and so on. However, tag collision problem greatly affects the performance of RFID systems by reducing bandwidth utilization and increasing identification delay etc. In this paper, we propose a dynamic query tree anticollision (DQTA) protocol, which dynamically adjusts the number of subgroups of each collision slot. Based on the number of consecutive colliding bits in tag response k, DQTA splits colliding tags into 2k subgroups. Dividing colliding tags into more appropriate subgroups, the number of collision slots and transmitted message bits are effectively reduced. Comparing with the most related stateofart works, the proposed DQTA protocol can identify tags with less time and fewer transmitting message bits.

An UltraLightweight RFID Mutual Authentication Protocol In some applications of the Internet of Things (IoT), for privacy preserving and authentication of entities, it is necessary to use ultralightweight cryptographic algorithms. In this paper, we propose a new ultralightweight authentication protocol between RFID components, in which only simple operations are used. In this protocol, the server has access to the data gathered by the tag in the same authentication phase through the reader interface, instead of sharing a secret key. The proposed protocol is secure against several attacks, such as replay attacks, denial of service, offline guessing attacks, modification attacks, full disclosure attacks and impersonation attacks, in addition to its practicality when compared to the previously proposed RFID authentication protocols. It also provides anonymity of tags against readers and the other tags involved in the protocol.