Urban Scale Context Dissemination in the Internet of Things: Challenge Accepted

Mobile applications envisaged in the Smart City rely on the capacity of acquiring context from a vast array of sensors and other data sources, to deliver context-aware services at an urban scale whilst leveraging the Internet of Things (IoT). This work analyses existing context dissemination techniques, encompassing both probabilistic and deterministic algorithms, and advocates the case for ACT (Adaptive Context Tries), a novel urban scale technique with a dissemination complexity and context availability that fulfils the requirements of Context-Aware Smart City applications. A number of enabling technologies and middleware solutions already exists supporting the provision and the sharing of context in small scale scenarios. It also shows that existing context dissemination techniques used in State of the Art middleware do not provide solutions that support context-aware applications in urban scale and dynamic, mobile environments. Results show ACT provides a scalable approach that incurs logarithmic growth in overhead with respect to the number of participating peers in the system without compromising the completeness, reliability, or timeliness of disseminated context.