QoS-OLSR 2.0: A Quality-of-Service Optimized Link State Routing protocol for Mesh Networks

This paper tackles the problem of frequent disconnections in the Quality-of-Service Optimized Link State Routing (QoS-OLSR) protocol due to mobility in mesh networks. Different routing protocols are proposed for mesh networks, such as Better Approach to Mobile Ad-hoc Networking (BATMAN), Optimized Link State Routing (OLSR), and QoS-OLSR 1.0. QoS-OLSR 1.0 improves the performance compared to the other protocols by incorporating cluster head formation and a Quality-of-Service metric used in cluster head selection. However, it still does not mitigate the impact of mobility in the formulated QoS metric. In this work, we propose and implement a cluster-based QoS-OLSR protocol for mesh networks that accounts for mobility. The work proposes a global QoS metric for nodes, calculated as the average quality of all neighbors' links. Also, a relative QoS metric is proposed and calculated based on the direct link with the neighbor and its global QoS. Based on the relative QoS, nodes in the network select cluster heads. In case of disconnection from the selected cluster head, the nodes join an existing cluster head to recover from disconnection. Cluster heads in the proposed protocol are responsible for determining Multi-point relays (MPRs) to 2-hop and 3-hop away cluster heads to enhance connectivity. The proposed protocol is implemented as a Linux-compatible protocol for emulations using Mininet-WiFi and compared to BATMAN and QoS-OLSR 1.0. The proposed protocol outperforms the benchmark protocols in terms of throughput, Packet Delivery Ratio, and Round Trip Time with low and high mobility nodes part of the network.