Wireless sensor network (WNS) are greatly differs from the traditional network architecture due to its energetic environment and limiting constraints and its calculated wireless applications. Because of these differences, security has become important issue. The path-based denial of service (PDoS) attacks harm the network services and has resulted in serious damage in the resource constrained WSNs. In a PDoS attack, an attacker can overwhelm sensor node and cluster head node to flood packets along the routing path so that intermediate node must keep active mode and exhaust the energy. In this paper we propose new creative approaches that work on the base station to detect mischievous attitudes. The proposed method is combined with triple exponential smoothing and Markov chain, so that it makes the finding results more accurate. At the same time Energy efficient, fault tolerance, scalability and connectivity and reliability are major challenges in wireless sensor network. Therefore, Energy efficient two level distributed clustering (EE-TLDC) Scheme is proposed with two level cluster head. The proposed scheme efficiently detects the malicious node and reduces the energy consumption in the network. Simulation shows that proposed scheme prolongs the stability period and reduces energy consumption in the network.

Keywords : Wireless Sensor Network (WSNs), Path-Based Denial of service (PDoS), Energy Efficient Two Level Distributed Clustering (EE-TLDC).