SecSyWiSe: A secure time synchronization scheme in wireless sensor networks

In this paper we suggest a protocol for secure data distribution in a one-way communication scenario aimed at time distribution for sensor networks. Our protocol is designed to support timestamps in any format, including repeating, resettable, and incomplete timestamps. The protocol requires a trusted powerful source node. We show that the protocol is immune to attacks including replay attacks, wormhole attacks, byzantine traitors, and node capture. These security features are achieved by the use of digital signatures with additional replay protection that is not based on time synchronization. Pulse delay attacks can be countered by the use of a filter accompaigned by a continuous timestamp format. The protocol relies on the source node to sign and broadcast messages with sufficient transmission power to reach all other nodes. These will not transmit any messages for time synchronization. We show that our protocol scales to networks of any density and allows for stealth applications. Conservative simulation results show that our protocol is more energy efficient for the sensor nodes than a comparable protocol.