Facilitating the Development of IoT Applications in Smart City Platforms

In smart city domain, several IoT platforms exist for supporting city managers and operators in controlling and managing events occurring in the city and making decisions to improve citizens’ quality of life. In such systems, for the combination of heterogonous events operators have to manually face the interoperability barriers that arise when dealing with IoT devices belonging to cross-domain IoT platforms. This paper focuses on how to provide city operators with visual and easy-to-use strategies for developing IoT applications that need to access and integrate data originated by various devices spread through a city that communicate according to different communication protocols, event formats, structures and sometimes meaning. The purpose of these strategies is to reduce the time required for the development of IoT applications and the number of mistakes in the configuration of the IoT devices. In details, we propose a solution developed in Node-RED, a visual programming tool for wiring together sensors, actuators and services. Our contribution aims at presenting a solution specifically tailored for domain experts who need to develop different kinds of analysis on city data who are not computer experts, but experts in monitoring weather, traffic, or events that happen in the city. A usability analysis is finally reported in order to assess the design strategies that we have developed.