Efficient Recurrent Low-Latency Scheduling in IEEE 802.15.4e TSCH Networks

Abstract

Recently, the interest in the Time-Slotted Channel Hopping (TSCH) mode of the IEEE 802.15.4e MAC layer has grown significantly. It is used especially in both Internet-of-Things (IoT) and industrial networks. TSCH uses channel hopping to increase link reliability and manages a time slotted schedule that instructs every node which action to take to allow for low-power operation. In our previous work we introduced the distributed Recurrent Low-Latency Scheduling Function (ReSF) that manages the TSCH schedule in such a way that it is optimized for power-constrained sensor networks where each node periodically sends recurrent measurement data to a sink and low-latency dissemination of the data is required. This work presents a more efficient version of ReSF and introduces three new contributions. First, we provide heuristics for the collision solving algorithm of ReSF. Second, we provide an additional feature to better avoid schedule collisions. Finally, we add increased support for sporadic traffic in ReSF networks. Extensive experimental results show a latency improvement up to 45.3 % with our previous work and up to 65.1 % with a state-of-the-art low-latency scheduling function.