ABSTRACT
Wireless Sensor Networks (WSN) consist of a large number of low-cost, low-powered sensor nodes that facilitate data collection in many diverse applications. They offer unprecedented opportunities for a broad range of monitoring and tracking applications in both civilian and military sectors (Chapter 1). In addition, the data aggregated from the sensor nodes are accessed from nodes within the network as well as external users. In all these applications, authentication and further encryption are fundamental
security requirements and are useful in mitigating impersonation attacks. They are also useful in preventing the ever-increasing DoS and DDoS attacks on limited resource constraint environments such as WSN. Three scenarios exist in WSN that require authenticated communication:
• Sink node to sensor nodes and vice versa • Sensor node with other sensor nodes • Outside user and sensor nodes
Most of the time, critical applications in WSN require a message to be sent as promptly as possible. The intermediate nodes between the sender and receiver are responsible for relaying the message to the receiver. If one of the nodes is compromised, the malicious node can inject falsified packets into the network while routing messages. Such an act could lead to falsified distribution of such messages and, in turn, deplete the energy levels of other honest nodes. Hence, there is a need to filter messages as early as possible by authenticating every message, consequently conserving relaying energy.
