Path Collision-aware Real-time Link Scheduling for TSCH Wireless Networks

Abstract

As low-power and low-rate WSNs are being widely used for industrial applications, the scheduling of such applications becomes a critical issue to guarantee meeting the stringent requirements of determinism and tight latencies.This paper studies the link scheduling problem for real-time industrial applications in time-slotted channel hopping (TSCH) networks.We propose a heuristic algorithm for centralized link scheduling referred to as path-collision aware least laxity first (PC-LLF) algorithm, which dynamically prioritizes the packets based on the laxity time to the end-to-end deadlines and the amount of collisions that messages might deal with along their designated paths to the destination device.We propose schedulability analysis of real-time applications scheduled under our prioritization approach over TSCH networks, based on the literature on real-time schedulability analysis of multiprocessors and distributed systems.We show that our methodology provides an improved schedulability condition with respect to the existing approaches.Performance evaluation studies quantify to quantify the performance of our proposed approach under a variety of scenarios.