Cooperative Transmission With Priority and Fairness in Edge Computing Systems

Edge computing plays an increasingly important role in the development of the Internet of Things (IoT). However, the explosive growth of terminal devices and unpredictable data flows make data transmission of edge computing systems challenging. In particular, it is crucial to efficiently transfer data from terminal devices to the edge server. In this paper, to ensure the fairness of network resource utilization and avoid starvation of low priority flows, we present a Collaborative Transmission Optimization Mechanism (CTOM) with priority and fairness. Based on the channel quality, CTOM first differentiates devices that can transmit data directly to the edge server from those that need to communicate with the edge server through relay nodes. To maximize transmission success ratio before deadlines of data flows, we perform flow scheduling based on its priority and allocate different bandwidth to different data flows to ensure fairness. In addition, we introduce the concept of energy harvesting (EH) for IoT devices. Equipped with an EH accessory, EH-enabled IoT devices extract energy from ambient resources, such as solar or radio frequency (RF) signals and thus improve energy efficiency. The simulation results verify that the transmission success ratio, the throughput, the average delay, and the energy consumption of CTOM are significantly improved compared with existing algorithms in the literature.