Design, Implementation and Testing of a Cost Function Based Scheduling Mechanism for a Water Management System

The IEEE 802.15.4 standard for low data rate and low power devices is currently in use by many Internet of Things (IoT) networks and control networks based on wireless sensor networks. One such application area is the water management systems for water supply and usage control. With the implementation of this standard in Contiki, no mechanism is present for control messages when other packets are being transmitted as well in the network. The gateway devices in these networks are usually exposed to more load in the network. During periods of high demand, packet dropping can occur at these nodes as well as other intermediate nodes that forward data. To address the high packet loss and congestion that takes place when the load level is high in a water telemetry management network, we propose a novel scheduling mechanism. This scheduling mechanism was implemented in the COOJA simulator using the Contiki operating system for wireless sensor nodes as an enhancement to carrier sense multiple access with collision avoidance (CSMA/CA). The results show that with the application of the proposed cost function (CF) scheduling strategy, packet loss is reduced and throughput is improved in multi-hop networks over the default scheduling mechanism. This mechanism can also be implemented in other rapid growing Internet of Things (IoT) networks and can improve performance when carrying high loads.