Improving QoS in Wireless Mesh Networks Using Heterogeneous and Hybrid Scheduling Design Approaches

Abstract

Wireless mesh networks (WMNs) offer low deployment costs and the potential to be implemented in smart rural applications where cost is a major concern. These applications generate heterogeneous data with different priorities. Carrier sense multiple access with collision avoidance (CSMA/CA) is widely used in WMNs due to the lack of a central controller for scheduling. In multi-domain networks, gateway devices are subjected to higher load levels. Since data is carried in a multi-hop fashion in WMNs, an increase in contention is observed, which results in an increase in collisions compared to single-hop networks. Enhanced distributed channel access (EDCA) was developed to provide quality of service (QoS) for multimedia traffic in single-hop networks. EDCA is known to starve lower-priority data in high-load scenarios. We propose to address these performance degradation issues through a proposed queue load control priority (QLCP) scheduling strategy, as well as through hybrid design networks, by configuring different scheduling strategies to edge and core nodes. Our results show that QLCP works best in edge nodes in hybrid networks with distributed coordination function (DCF) in the core nodes and that choice of an appropriate scheduling strategy can have a significant impact on the QoS achievable in WMNs.