Abstract. Security of Wireless sensor network (WSN) becomes a very important issue with the rapid development of WSN that is vulnerable to a wide range of attacks due to deployment in the hostile environment and having limited resources. Intrusion detection system is one of the major and efficient defensive methods against attacks in WSN. A particularly devastating attack is the sleep deprivation attack, where a malicious node forces legitimate nodes to waste their energy by resisting the sensor nodes from going into low power sleep mode. The goal of this attack is to maximize the power consumption of the target node, thereby decreasing its battery life. Existing works on sleep deprivation attack have mainly focused on mitigation using MAC based protocols, such as S-MAC, T-MAC, B-MAC, etc. In this article, a brief review of some of the recent intrusion detection systems in wireless sensor network environment is presented. Finally, we propose a framework of cluster based layered countermeasure that can efficiently mitigate sleep deprivation attack in WSN. Simulation results on MATLAB exhibit the effectiveness of the proposed model in detecting sleep-deprivation attacks.Keywords: WSN, Sleep Deprivation Attack, Cluster, IDS, Insomnia. IntroductionWireless sensor network (WSN) refers to a system that consists of number of low-cost, resource limited sensor nodes to sense important data related to environment and to transmit it to sink node that provides gateway functionality to another network, or an access point for human interface. WSN is a rapidly growing area as new technologies are emerging, new applications are being developed, such as traffic, environment monitoring, healthcare, military applications, home automation. WSN is vulnerable to various attacks such as jamming, battery drainage, routing cycle, sybil, cloning. Due to limitation of computation, memory and power resource of sensor nodes, complex security mechanism can not be implemented in WSN. Therefore energy-efficient security implementation is an important requirement for WSN.A sleep deprivation attack (battery drainage) is a particularly severe attack in WSN because recharging or replacing node batteries in WSN may be impossible. In this type of attack, intruder forces the sensor nodes to remain awake; so that they waste their energy. This attack imposes such a large amount of energy consumption upon the limited power sensor nodes that they stop working and give rise to denial of service through denial of sleep.In this paper a survey of on-going research activity is presented. This is followed by a comparative analysis of the recent ID schemes. This paper concludes with a glimpse of the proposed model for detecting sleep deprivation attack.