Cell Allocation Method for Scalability Enhancement in TSCH Autonomous Scheduling

Recently, there has been a rapid increase in the use of IoT devices across various industrial sectors. The IEEE802.15.4 Time-Slotted Channel Hopping (TSCH) MAC protocol is widely utilized to construct reliable wireless networks with resource-constrained devices. Although the existing TSCH autonomous cell scheduling mechanism allows for cell allocation without additional control overhead, it suffers from issues of cell conflicts and limited network scalability. Previous efforts, such as ALICE and ECA, have attempted to reduce cell conflicts but still require improvements. This paper proposes a novel technique that enhances ECA by propagating timeslot offsets from parent nodes and introducing an Allocation Index, thereby removing cell conflicts and improving network scalability. The technique was implemented in Contiki-NG and tested using the Cooja simulator. Experimental results show that, compared to ALICE, the Packet Arrival Rate (PAR) improved by up to 24%, and the End-to-End latency performance was enhanced by up to 58%.