Efficient Scheduling Function for IETF 6TiSCH Networks Based on Multiweight Evaluation and Improved Q-Learning

The IETF 6TiSCH Working Group proposed a highly reliable and low-power industrial wireless network protocol stack, which integrates IEEE 802.15.4e time-slotted channel hopping (TSCH) with IPv6 protocols. Scheduling is crucial in the 6TiSCH protocol stack, as it determines when a node sends or receives network packets on specific timeslots and channels. However, the current resource scheduling suffers from random timeslot selection, channel collisions, and high energy consumption, all of which degrade network performance. In this article, we propose an innovative scheduling function consisting of three core components. First, a multiweight quality evaluation is proposed to enable precise timeslot selection, improving resource allocation efficiency. Second, an improved Q-Learning-based scheduling mechanism is proposed to generate optimal parameters for multiweight evaluations, which is based on the global network state implemented at the edge router. Third, a pseudo-random channel selection strategy is proposed to effectively reduce channel congestion and interference. Extensive experimental results demonstrate that our function achieves a latency improvement of up to 55% compared to state-of-the-art low-latency scheduling, and along with an enhancement of up to 6% in the packet delivery ratio.