Abstract:In this paper, a data authenticate algorithm based on cooperation watermarks is proposed for recognition and filtering false data and replayed packets. In each packet, two kinds of watermarks are embed into data packets. One is robust watermark for the authentication of sender’s identification and the freshness of data. The other is Semi-Fragile watermark for the authentication of content generated by t witnesses. The proposed algorithm has several advantages. Firstly, different watermarks have no interaction with one another. Secondly, single sensor node can independently extract the watermark to validate data packets while nodes have no ability to modify and fabricate watermark. Theoretical and experimental results show that the algorithm has good performance in the peak value signal to noise ratio and signal to noise ratio by embedding watermarks into packets under most circumstances. And the algorithm is of high sensibility to malicious modified data, of robustness to some noise disturbance, lossy compression and so on. The new algorithm has less communication cost and more capability for the false data recognition and filtering compared with the existing algorithm based on MAC (message authentication code) schemes.