Distributed Region-Based Monitoring in Low-Power Listening Wireless Sensor Networks

Advancement in IoT technology and the concept of Information-Centric Networking lead to less importance of node individuality since several nodes can work interchangeably. Multiple sensor nodes can be grouped into a region and monitored as one instance to guarantee sufficient coverage over the region. Therefore, a single node fault often does not need to be reported unless it is the last node in the region. In addition, there are occasions where a central monitor station cannot rely on continuous data delivery from nodes or regions to decide whether they are still alive, such as situations when nodes are deployed to detect rare events. Moreover, low-power listening MAC protocols, which significantly help reducing power consumption while nodes are mostly idle, put a lot more work on the transmission process. In such situations it is desirable to minimize status reports to the central monitor station. A distributed region-based monitoring scheme, or DRMON, is then proposed to facilitate this circumstance. This approach designates a representative to each region so that it can be used as an indicator of the region's status with a mechanism to re-elect a new representative until all nodes in the respective region are dead, implying region inactiveness. We evaluate the suitability of DRMON over various scenarios in two aspects: centralized vs. distributed monitoring schemes and individual-based vs. region-based monitoring schemes. Simulation results indicate that region-based schemes outperform the individual schemes in terms of power consumption and scalability when the number of regions is low. The distributed schemes also yield better efficiency in terms of message overhead and load distribution. In addition, detection accuracy of all schemes is not significantly different and fault detection delay is guaranteed. This outcome suggests that in the case where existence of individual node is out of concern, distributed region-based fault monitoring scheme could be employed to reduce energy usage and lower message overhead while retaining the detection accuracy.

Secure Trust Aware Hybrid Key Management Routing Protocol for WSNs for the Application of IoT

Secure Trust Based Key Management Framework for Wireless Sensor Networks (WSNs) to protect the forwarded packets from intermediary malicious nodes. The proposed method continuously ensures the trustworthiness of cluster heads by replacing them as soon as they become malicious and can dynamically update the packet path to avoid malicious routes. Unlike the other methods, the process is distributed among the nodes to minimize routing overhead and to conserve energy. The fundamental process of moving node to non-switchable Low Power Listening (LPL) state assists energy conservation. Trust based neighbor selection is carried out using Gateway node (GW) and Monitoring Node (MN) monitors other node activities so as to ensure security in the network. The manifold process integrated improves network performance in terms of throughput, retaining network lifetime and conserving energy utilization at midst the presence of adversary nodes. The proposed method can significantly outperforms traditional cluster based routing protocols that do not use trust concept in selecting the forwarding nodes in packet delivery ratio. Comparisons and analysis have shown the effectiveness of the proposed scheme.