Dipartimento di Ingegneria informatica, automatica e gestionale

The growth of large scale sensing applications (as in the case of smart cities applications) is a main driver of the fog computing paradigm. However, as the load for such fog infrastructures increases, there is a growing need for coordination mechanisms that can provide load balancing. The problem is exacerbated by local overload that may occur due to an uneven distribution of processing tasks (jobs) over the infrastructure, which is typical real application such as smart cities, where the sensor deployment is irregular and the workload intensity can fluctuate due to rush hours and users behavior. In this paper we introduce two load sharing mechanisms that aim to offload jobs towards the neighboring nodes. We evaluate the performance of such algorithms in a realistic environment that is based on a real application for monitoring in a smart city. Our experiments demonstrate that even a simple load balancing scheme is effective in addressing local hot spots that would arise in a non-collaborative fog infrastructure.