Reversible watermarking algorithm for wireless sensor network using method of multi-node negotiation

Watermark technology has been used for verifying the integrity and correctness of sensor collected data. However, most of the watermark technologies used in wireless sensor networks are not reversible. The embedded watermarks make some damage to the sensor collected data. In this paper, based on difference expansion algorithm, we propose a reversible watermark algorithm aiming to solve the data recovery problem in wireless sensor networks. Target on the sensors´ loosely organization problem and sensor´s weak defensiveness problem, the proposed algorithm splits the whole watermark into several segments and assigns the segments randomly to sensors, which enhance the ability to resist collusion attack. Meanwhile, we use a pair of synchronous random number generators for sensors and the sink to solve the data freshness distinguished problem.