Secured Flooding Time Synchronization Protocol

This research aims to complement security vulnerability of Flooding Time Synchronization Protocol (FTSP), which is currently one of the most sophisticated approaches for time synchronization in wireless sensor networks (WSNs). FTSP has advanced features like implicitly dynamic topology and high accuracy time, but its original design does not consider security issues. In order to defend against attacks from malicious nodes, we propose several techniques to reinforce the structure of FTSP. A reference node selecting mechanism is proposed to reduce the effect of multiple reference nodes, and four filters are proposed to defend against seqNum attack, global time attack, and node replication attack. Experiments of the above attacks are performed and the results show that all these attacks can be defended when sequence number blacklist filter and global time blacklist filter are adopted. Furthermore, fluctuation filter helps to reduce the data collection time from 10 sending cycles to 5 cycles when detecting global time attack.