A Novel Secure Pairwise and Groupwise Synchronizing Scheme in WSN

Existing solutions yet for time synchronization in sensor networks are not resilient to malicious behavior from external attackers or internally compromised nodes. The feasibility of a pulse-delay attack (external attack), whereby an attacker can introduce arbitrarily long delays in the packet propagation time directly can affect the achieved synchronization precision. It is assumed in the proposed approach that all nodes are directly connected to one another. Hence, propagation delay is minimal. The proposed approach is able to overcome from external as well as internal attacker problems in group synchronization. The external attacks are resolved with the help of message authentication codes (MAC) and the use of private keys and internal attacks are found out on the basis of send and receive time. Once the group is secure from external as well as internal attacker i.e., no malicious node is present in the group then each node synchronizes to the common clock in the group.