Tsch-Varba – Dynamic Channel Allocation with Variable Bandwidth in Tsch Networks

The transmission and reception of packets in wireless networks suffer from interference, packet collisions, and bottlenecks that increase latency and reduce network throughput. The high demand for a set of links can turn the network inefficient and even dead. The TSCH networks try to avoid collisions by scheduling channels and time. However, there is still the presence of bottlenecks, and an improvement is required. Channels with wider bandwidth can improve the network in bottleneck regions. Therefore, this paper proposes a scheduling algorithm to dynamically allocate channels with variable bandwidth to reduce bottlenecks and improve network performance. The scheduling and channel allocation happen using the conflict mapping method where congestion is identified. A set of nodes compete for the same communication channel resources and sending time, organizing them to improve the network performance. This work proposes a procedure for allocating channels with bandwidth proportional to the demand for packets per link. We implemented the algorithm in the Contiki-NG platform. Results show a reduction in the slot time duration and improvement in packet delivery.