Smart City IoT Services Creation Through Large-Scale Collaboration

Smart cities solutions are often monolithically implemented, from sensors data handling through the provided services. The same challenges are regularly faced by different developers, for every new solution in a new city. Expertise and know-how can be reused and the effort shared. In this article, we present the methodologies to minimize the efforts of implementing new smart city solutions and maximizing the sharing of components. The final target is to have a live technical community of smart city application developers. The results of this activity come from the implementation of 35 city services in 27 cities between Europe and South Korea. To share efforts, we encourage developers to devise applications using a modular approach. Single-function components that are reusable by other city services are packaged and published as standalone components, named atomic services. We identify 15 atomic services addressing smart city challenges in data analytics, data evaluation, data integration, data validation, and visualization. Thirty-eight instances of the atomic services are already operational in several smart city services. We detail in this article, as atomic service examples, some data predictor components. Furthermore, we describe real-world atomic services usage in the scenarios of Santander and three Danish cities. The resulting atomic services also generate a side market for smart city solutions, allowing expertise and know-how to be reused by different stakeholders.