ISO/IEC 21823-3:2021

This document provides the basic concepts for IoT systems semantic interoperability, as described in the facet model of ISO/IEC 21823-1, including: ° requirements of the core ontologies for semantic interoperability; ° best practices and guidance on how to use ontologies and to develop domain-specific applications, including the need to allow for extensibility and connection to external ontologies; ° cross-domain specification and formalization of ontologies to provide harmonized utilization of existing ontologies; ° relevant IoT ontologies along with comparative study of the characteristics and approaches in terms of modularity, extensibility, reusability, scalability, interoperability with upper ontologies, and so on, and; ° use cases and service scenarios that exhibit necessities and requirements of semantic interoperability.