Energy Aware Provisioning in Solar Powered WLAN Mesh Networks

WLAN mesh networks are often installed to provide wireless coverage for temporary events. In these types of networks, the WLAN mesh nodes can sometimes be operated using an energy sustainable source such as solar power. Resource provisioning consists of pre-assigning each node with a solar panel and battery combination that is sufficient to prevent node outage for the duration of the deployment. This is done by assuming a temporal load profile for each node, which is then used to perform the assignment using historical solar insolation data for the desired deployment location. Unfortunately, this methodology cannot take into account the state dependencies which occur when the network uses energy aware routing, and therefore the system may be over-provisioned. In this paper we propose a methodology for WLAN mesh node resource assignment that incorporates energy aware routing into the assignment algorithm. The problem consists of determining a network-wide minimum cost resource assignment subject to satisfying the input load profile. A genetic algorithm (GA) has been developed for this purpose. Our results show the large resource savings that energy aware resource assignment can achieve when compared to that done using the conventional methodology. We also study the competitive ratio of both resource assignment schemes and show that for small traffic overloading, energy aware routing performs better than shortest path routing in networks which are provisioned using the proposed methodology.