Topology Control in Fog Computing Enabled IoT Networks for Smart Cities.

Over the last few years, there has been a tremendous focus on smart cities and latency-sensitive Internet of Things (IoT) applications. Fog Computing (FC) is a paradigm that has been envisioned to mitigate the bottlenecks in traditional IoT networks with respect to latency by bringing storage and processing resources close to the IoT devices. In this paper, we propose a complete set of Topology Control (TC) techniques for constructing and managing a large-scale smart city IoT network. We approach the problem of TC in two phases: Construction Phase and Maintenance Phase. In the Construction Phase, we build a cost-effective IoT network consisting of fog gateways, and in the Maintenance Phase, we optimize the resource utilization in the system. We propose efficient algorithms in each of the phases to realize our objectives, and with extensive simulation based on real and experimented IoT data sets, we demonstrate the effectiveness of our algorithms by comparing with existing algorithms. In the Construction Phase, compared to the existing NewIoTGateway-Select (NIGS) algorithm, our Hungarian based Topology Control (HTC) algorithm performs 45% and 42% better in terms of overall system cost and the number of required gateways, respectively. In the Maintenance Phase, our Vacation based Resource Allocation (VRA) algorithm enhances the utilization of processing resources by 12x without adversely affecting the latency constraints of the applications. Similarly, our Dynamic Resource Allocation (DRA) algorithm enhances the utilization of storage resources by 4x without adversely affecting the latency constraints of the applications.