Scheduling in 6TiSCH Networks via Max-Product Message-Passing

Industrial Internet of Things (IoT) wireless solutions are getting increased attention both in research and industry due to proliferation of low cost IoT solutions and benefits of massive data collection and analysis. One of the recently proposed solutions for IIoT is the 6TiSCH (IPv6 over the TSCH mode of IEEE 802. 15.4e) protocol stack. However, efficient design of 6TiSCH protocol, and in particular, scheduling strategies that would maintain both high throughput and network reliability, is an open problem. In this paper, we provide an initial study of how this problem can be modelled and solved using the probabilistic graphical models framework and adjoined message-passing methods. In particular, we represent the scheduling problem as the maximum weighted independent set (MWIS) problem, which is generally known to be NP-hard, and solve it approximately but efficiently using the message-passing max-product belief propagation (BP) method. The proposed method is described in detail and demonstrated on a toy example of an IEEE 802. 15.4e network.