domOS Common Ontology: Web of Things Discovery in Smart Buildings.

According to the 2021 energy efficiency report of the European Union (EU), 75% of the existing buildings in the EU have been assessed as energy-inefficient. Internet of Things (IoT) services are developed to increase energy efficiency in buildings. The W3C recommends the use of the W3C Web of Things (WoT) standard to enable IoT interoperability on the Web. However, the ability to discover IoT devices available in the WoT remains a challenge due to the lack of ontologies integrating WoT Thing Descriptions in smart buildings. We present in this paper the domOS Common Ontology (dCO) to achieve the W3C WoT discovery in smart residential buildings in 5 demonstration sites of the H2020 EU domOS project. This ontology integrates the WoT Thing Description with IoT concepts, i.e. IoT devices and building topology, in order to leverage the W3C WoT Discovery. We made the WoT Discovery implementation available for the community.