A Scheduling for Slotted-CSMA-based Wireless Mesh Networks to Reduce Delivery Delay

Abstract

In this paper, we propose a new scheduling problem for WMNs based on slotted-CSMA. Slotted CSMA is a mechanism that divides a single frequency channel into several time slots where CSMA functions. With a schedule that matches links and slots, each node transmits frames in the assigned slot to avoid collision of frames. CATBS (CSMA-Aware Time-Boundable Scheduling) is a slotted-CSMA-based WMN architecture with a scheduling algorithm. However, it suffers from large end-to-end delay due to its long slot time that allows transmitting several frames within a single slot. This paper extends the scheduling problem of CATBS to consider inter-slot collision to reduce the overhead of collision at slot boundaries even if using short slot time. Evaluation results shows that the proposed scheduling problem reduces the overhead that arises at slot boundaries, and improves communication performance when using short time slots.