SeamFlow: Seamless Flow Forwarding in Energy Harvesting-Enabled Access Points of SDWLAN

The deployment of software-defined wireless local area networks (SDWLANs) in hostile regions requires solar energy harvesting-enabled battery-powered access points (APs). The aforementioned APs replenish batteries and forward data flows by avoiding the problem of frequent energy outages. In this work, we propose a scheme called SeamFlow to place APs in energy harvesting mode without disrupting the forwarding of flows. In contrast to previous works, we focus not only on the energy replenishment of battery, but also, seamless forwarding of flows without violating flow constraints. Specifically, we formulate SeamFlow as a two-phase optimization problem - a) optimal selection of APs and b) finding forwarding paths. As solving both optimization problems are NP-hard, we propose two greedy-heuristic schemes to solve them in polynomial time. Extensive simulation results show that proposed scheme reduces flow forwarding cost by 24% and 16%, per-flow energy consumption by 27% and 21%, and flow violations by 92% and 86% compared to the benchmarks using random and grid topologies, respectively.