PASCCC: Priority-based application-specific congestion control clustering protocol

Wireless sensor networks comprise resource-starved sensor nodes, which are deployed to sense the environment, gather data, and transmit it to a base station (BS) for further processing. Cluster-based hierarchical-routing protocols are used to efficiently utilize the limited energy of the nodes by organizing them into clusters. Only cluster head (CH) nodes are eligible for gathering data in each cluster and transmitting it to a BS. Unbalanced clusters result in network congestion, thereby causing delay, packet loss, and degradation of Quality of Service (QoS) metrics. In this study, we propose a priority-based application-specific congestion control clustering (PASCCC) protocol, which integrates the mobility and heterogeneity of the nodes to detect congestion in a network. PASCCC decreases the duty cycle of each node by maintaining threshold levels for various applications. The transmitter of a sensor node is triggered when the reading of a specific captured event exceeds a specific threshold level. Time-critical packets are prioritized during congestion in order to maintain their timeliness requirements. In our proposed approach, CHs ensure coverage fidelity by prioritizing the packets of distant nodes over those of nearby nodes. A novel queue scheduling mechanism is proposed for CHs to achieve coverage fidelity, which ensures that the extra resources consumed by distant nodes are utilized effectively. The effectiveness of PASCCC was evaluated based on comparisons with existing clustering protocols. The experimental results demonstrated that PASCCC achieved better performance in terms of the network lifetime, energy consumption, data transmission, and other QoS metrics compared with existing approaches.