Abstract: A wireless sensor network (WSN) has important applications such as remote environmental monitoring and target tracking. This has been enabled by the availability, particularly in recent years, of sensors that are smaller, cheaper, and intelligent. These sensors are equipped with wireless interfaces with which they can communicate with one another to form a network. The design of a WSN depends significantly on the application, and it must consider factors such as the environment, the application’s design objectives, and cost, hardware, and system constraints. The sensor nodes will perform significant signal processing, computation, and network self-configuration to achieve scalable, robust and long-lived networks.. More specifically, sensor nodes will do local processing to reduce communications, and consequently, energy costs. We believe that most efficient and adaptiverouting model for WSN is cluster based hierarchical model. For a cluster based sensor network,the cluster formation plays a key factor to the cost reduction, where cost refers to the expense ofsetup and maintenance of the sensor networks. In this paper, we will take a more security in WSN and discuss countermeasures. The goal of our survey is to present a comprehensive review of the recent literature since the publication of [I.F. Akyildiz, W. Su, and Y. Sankarasubramaniam. Cayirci, A survey on sensor networks, IEEE Communications Magazine, 2002]. Following a top-down approach, we give an overview of several new applications and thenreview the literature on various aspects of WSNs. We classify the problems into three differentcategories: (1) internal platform and underlying operating system, (2) communicationprotocol stack, and (3) network services.
Keywords: Wireless sensor network (WSN), Network Security, Micro-Electro-Mechanical Systems (MEMS)