The origin of most data in the world comes from closed-world systems. Forms, logging systems, and sensors all generate data in predefined structures where the schema is known in advance. Yet when people enter the world of RDF, interested only in adding semantics to their data, they’re confronted with an all-or-nothing proposition: “Here’s a triple store, learn OWL, RDF/XML is bad but your code must be able to process it, accept that you live in an open-world. Take it or leave it.”
But many use cases don’t require the full semantic web stack. This post explores how closed-world systems can benefit from RDF semantics without adopting the full semantic web stack. We’ll cover when closed-world assumptions make sense, how to bridge closed and open-world systems, practical examples from sensors, UIs, and IoT, new SHACL features in development that enable these patterns, and what the RDF community needs to do to make this easier.