ComLoB: Link quality and queuing delay based composite routing protocol for traffic Load Balancing in WSNs

The popularity of wireless sensor networks (WSNs) is increasing due to their ease of deployment and auto-configuration capabilities. They are used in different application domains including data collection with convergecast scenarios. In convergecast, all collected data are destined to one common node usually called the sink. In case of high traffic load, this many- to-one data collection scenario causes queue overflow mainly in nodes located near the sink. Sensor nodes are known for their limited storage capacities which makes the packet queue overflow even more critical. This issue is often avoided by the routing protocol. In this paper we propose a link quality and delay based Composite Load Balancing routing protocol (ComLoB) that fairly distributes traffic load to avoid congestion. It also integrates active queues monitoring to prevent dropping packets due to queues overflow. Simulation results on Contiki OS Cooja simulator showed that ComLoB achieves a better packet delivery ratio and much less queue overflow compared to standard routing protocols such as RPL and HopCount. We also validate our proposal through experimentation on TelosB motes.