common clock. In the proposed approach although it is considered that cluster head ( a group leader ) is non-malicious but it may be malicious. A malicious cluster head will not report exact time as which it sends reference packets to all intended receivers, i.e. it will send a false time to all receivers. This false time will be used by group members for synchronisation. Hence all group nodes will synchronise to false time. This can be overcome by fixing the initial sender node as non-malicious. The proposed approach is able to overcome from external as well as internal attacker problems is group synchronisation. The external attacks are resolved with the help of MAC message authentication codes and the use of private keys and the internal attacks is finding out on the basis of send and receive time. Fei et …show more content…
RFID is a non-contact automatic identification technology through wireless radio frequency recognizing. RFID authentication protocols; ESAP and WISP are vulnerable to the timing attack. Inspired by the monotonically increasing timestamp mechanism in the two protocols, we present a novel mutual security authentication protocol TMAP which can resist desynchronization attacks amongst other things, especially timing attack. The protocol TMAP provides mutual authentication for the server and the reader, decreases the computation both of the tag and the server and operates in the mobile RFID systems, which is promising practical application especially in the mobile internet and cloud computing developing rapidly nowadays. Due to the limitation of energy, computing and storage resources of RFID tags, the mature encryption algorithm and authentication mechanisms in the field of communication security cannot be transplanted to the low cost RFID system directly. The TMAP protocol operates in mobile RFID system on assumption that the channel between the server and the reader is not