A Rank-based Mechanism for Service Placement in the Fog

As communications evolve to give space to new applications, such as augmented reality and virtual reality, new paradigms arise to provide essential characteristics like lower latency levels, mobility support, and location awareness. Such is the case of Fog computing, which extends from the well-known Cloud computing paradigm by bringing processing, communications, and storage capabilities to the edge of the network. By offering these novel features, also new challenges emerge that call for the design and implementation of orchestration mechanisms to deal with resource management. One of these mechanisms is related to the service placement, which consists in the selection of the appropriate execution node for the applications according to a specific optimization objective. In this paper, an Integer Linear Programming model for service placement aimed at latency reduction of popular applications is proposed. Furthermore, a heuristic based on the PageRank algorithm, called Popularity Ranked Placement, is also introduced. Simulation results show that the heuristic has lower execution times and is able to better balance the load in the network nodes, while being close to the ILP-based solution latency levels.