Security issues and countermeasures in wireless sensor networks

Sensor networks pose unique security challenges because of their inherent limitations in communication and computing. The deployment nature of sensor networks makes them more vulnerable to various attacks. Sensor networks are deployed in applications where they have physical interactions with the environment, people and other objects making them more vulnerable to security threats. We envision that sensor networks would be deployed in mission critical applications like battlefield, security of key land marks, building and bridges, measuring traffic flow, habitat monitoring and farming. Inherent limitations of sensor networks can be categorized as node and network limitations. The privacy and security issues in sensor networks raises rich research questions. Dense deployment of sensor networks in an unattended environment makes sensor nodes vulnerable to potential attacks. Attackers can capture the sensor nodes and compromise the network to accept malicious nodes as legitimate nodes. Once within the network, attackers can rage variety of attacks. We expect Moore's law to be applied to drive down the cost of sensor nodes instead of improving its resources and performance.Hardware and software improvements will address these issues at some extent but complete secure sensor networks require deployment of countermeasures such as secure key management, secure routing and light weight encryption techniques. This chapter provides an overview of security issues known so far in sensor networks, and the countermeasures against these issues followed by key management schemes and secure routing protocols. The key management and routing protocols discussed in this chapter are the resilient solutions towards the attacks identified so far; however, research towards a complete secure sensor network is still in its infancy stages.