Reliable Dynamic Packet Scheduling with Slot Sharing for Real-Time Wireless Networks

Abstract

In order for real-time wireless networks (RTWNs) to achieve desired Quality of Service (QoS) for real-time sensing and control, effective packet scheduling algorithms play a critical role, especially in the presence of unexpected disturbances. Most existing solutions in the literature focus either on static or dynamic schedule construction to meet the desired QoS requirements, but have a common assumption that all wireless links are reliable. However, this assumption is not realistic in real-life settings. To address this drawback, this paper introduces a novel reliable dynamic packet scheduling framework, called RD-PaS. RD-PaS can not only construct static schedules to meet both the timing and reliability requirements of end-to-end flows in RTWNs, but also construct new schedules rapidly to handle abruptly increased network traffic induced by unexpected disturbances while minimizing the impact on existing network flows. Through judiciously sharing time slots among tasks, RD-PaS can significantly reduce the number of required time slots to meet the system reliability requirement and improve the network throughput. The functional correctness of the RD-PaS framework has been validated through its implementation and deployment on a real-life RTWN testbed. Extensive simulation-based experiments have also been performed to evaluate the effectiveness of RD-PaS, especially in large-scale network settings.