Stripe: a Distributed Scheduling Protocol for 802.15.4e TSCH Networks

Les rapports de recherche du LIG - ISSN: 2105-0422The 802.15.4e Time Slotted Channel Hopping (TSCH) mode defines how nodes operate according to a common shared schedule that determines which device may transmit frames on a given channel and during a given timeslot. By taking advantage of channel diversity, TSCH increases reliability and cell allocation to two nodes for a given transmission results in reduced collision probability. As the standard does not specify how to construct the common schedule, there is a need for finding adequate scheduling algorithms. In this paper, we propose Stripe, a distributed scheduling protocol that allocates timeslots in temporal alignments having the property that multi hop forwarding of packets benefits from the minimal delay. Stripe ensures short delays both for upward and downward traffic. The protocol comprises two phases: the relocation phase that reconfigures the random pre-allocated cells in a schedule fitting convergecast traffic and a reinforcement phase that schedules additional cells to support the traffic generated and relayed by each node towards the sink. We evaluate Stripe with an enhanced 6TiSCH simulator and compare its performance with Orchestra [1]. The results from extensive simulations show that Stripe presents fast convergence, short delays, and improved packet delivery ratio