Abstract: The appearance of sensor network as one of the presiding technology in the coming decades has given numerous unique challenges to researchers. These sensor networks consist of large set of homogenous nodes which have limited computed resources. A lot of real world applications on sensor network have been proposed in research literatures. When sensor networks deploy in a unintended or hostile environment, security issues becomes a central concern, as they are prone to different types of malicious attacks. In this paper we present the survey of security issues, attacks with countermeasures in wireless sensor network (WSN). Conclusion and future scope of the work has also been outlined.

Keywords: Wireless Sensor Networks, Security, Threats, Attacks.