Energy Sustainable IoT Scheduling in a Fog/IoT Interplay

In the Internet of Things/Fog interplay we define a novel problem, namely Max Sustainable Scheduling, and propose an algorithm for its solution. This problem arises when an IoT device and a Fog node stipulate a service-level agreement that limits the computational power that the Fog node devotes to serve the IoT device and that defines the corresponding costs, which are dependent on the actual amount of computational power required and on the associated energy costs for the Fog node. As the cost of energy is variable over time, this agreement is an incentive for the IoT device to schedule its activities so to modulate the implied load on the Fog node, in order to take advantage of the variable costs of the energy and to maximize the overall quality of its output. We discuss the pragmatics of the solver and we propose an efficient algorithm to solve the problem on the IoT device itself.