This standard specifies the requirements to be satisfied by reference architectures (RA) applicable to entities of interest such as software, systems, enterprises, missions, systems of systems, families of systems, products (goods or services), product lines, technologies, and business domains. The application areas of this standard include the following: artificial intelligence (AI), machine learning (ML), Internet of Things (IoT), cloud computing, big data, smart cities, smart manufacturing, cybersecurity, digital twin, telecommunications, aerospace defense, banking, finance, insurance, energy, automotive, logistics, hospitality, healthcare, supply chain, transportation, manufacturing and production, agriculture, and infrastructure. Some RAs are not specific to a domain of their application, rather they capture a domain of interest for many application areas, e.g., the domain of security architecture is relevant for many application areas.