S.Suganya, M.Thenmozhi
Reprogramming is an important operation to wireless sensor networks. Reprogramming is based on update commands, adding new functionalities or removing bugs in WSN’s. Reprogram has two approaches. Namely, centralized and distributed approach. Distributed approach has more benefits compare to centralized approach .In existing ,SDRP protocol was introduced in distributed approach for secure reprogram. This protocol has some drawbacks. To overcome, In this paper, we propose an effective one way hash chain algorithm is introduce to provide more confidentiality and also increase the energy in an efficient manner.