Dynamic and cooperative nature of sensor nodes in Wireless Sensor Networks raises question on security. Various researchers work in this direction to spot malicious, selfish and compromised nodes. Various mechanisms followed are uniqueness of clustering, reputation system and an operation at specific nodes. LEACH is a hierarchical protocol in which most nodes transmit to cluster heads, and the cluster heads aggregate and compress the data and forward it to the base station (sink). Each node uses a stochastic algorithm at each round to determine whether it will become a cluster head in this round. Clustering process carried out in two stages takes the role of the reputation scheme and reveals specific operation at CH, IN and MNs beside their usual activities in cluster based wireless sensor networks. This paper mentioned the final structure of the security framework, corresponding attacks and defense mechanism of the model. It also discusses various security level processes of wireless sensor networks. Results implies that in a cluster-based protocol such as LEACH in which optimally 5% of the nodes are cluster heads it is likely that a significant portion of the network can be paralyzed or the entire network disabled, in the worst-case scenario, if these cluster heads are compromised. Our main contribution in this paper is our novel approach in maintaining trusted clusters through a trust-based decision-making cluster head election algorithm.
Worst Case Age of Information in Wireless Sensor Networks: A Multi-Access Channel
