Towards Semantic Web of Things: Reference Architecture and Gap Analysis

Internet of Things (IoT) connects objects and allows data exchange between smart things and the Internet. Web of Things (WoT) further integrates smart things into the Web architecture by leveraging existing standardized Web technologies. In this paper, we envision Semantic Web of Things (SWoT), aiming to exchange semantically rich and machine understandable information with smart things. This article discusses the landscape of IoT and WoT through the past and its future prospects, presents a SWoT reference architecture, and conducts a gap analysis. Aiming to highlight the deficiencies of existing solutions, we carry out a gap analysis with respect to (i) extension of WoT, (ii) semantic knowledge base, (iii) semantic reasoning, (iv) semantic interoperability, and (v) semantic service composition. Based on the results of our analysis, we conclude this article with a list of recommendations in order to fill the gaps. The main contributions pertain to a SWoT reference architecture with key SWoT building blocks and an analysis of technologies to support SWoT.