The basic architecture of the Open Semantic Framework pivots around the OSF Web Services; there are now nearly 30 providing a wealth of functionality. Full CRUD under user permissions and security is provided to all digital objects in the stack. This OSF access layer provides a means to access best-of-breed data management and indexing engines through uniform RESTful Web services. These access services both: 1) abstract away the complexity of the individual engines, while 2) enabling combined capabilities orchestrated by OSF not available from the engines alone.
This intermediate OSF Web Services layer may also be accessed directly via API or command line or utilities like cURL, suitable for interfacing with standard content management systems (CMSs), or via a dedicated suite of connectors and modules that leverage the open source Drupal CMS. These connectors and modules, also part of the standard OSF stack and called OSF for Drupal, natively enable Drupal's existing 10,000 modules and ecosystem of developers and capabilities to access OSF using familiar Drupal methods.
This basic architecture from user interface to engines is quite simple in design:
In this design, OSF is the meat in the sandwich that links a proven content management system, Drupal, with proven semantic technology engines such as Virtuoso, GATE, OWL API 2, and Solr. What had heretofore been unconnected capabilities are now integrated via the OSF glue.
The premise of the entire stack is based on the RDF data model. RDF provides the ready means for integrating existing structured data assets in any format, with semi-structured data like XML and HTML, and unstructured documents or text. The OSF framework is made operational via ontologies that capture the domain or knowledge space, matched with internal ontologies that guide OSF operations and data display. This design approach is known as ODapps, for ontology-driven applications.
The OSF stack is supported by complete documentation, automated installation routines, comprehensive unit and end-to-end tests, and workflows and use case studies to ease adoption. SD and its partners provide experienced support and extension services.