ST 2005 Note #6 - Using semantic technologies today

Current state

The semantic web is here and the supporting standards; XML, RDF and OWL are current W3C recommendations. Vendors and the open source community are providing tool support for ontologies. Some examples are:

• Open Source
  
  
  
  • Jena 2 - HP's semantic web framework.
    
  • SWOOP - An ontology editor from mindswap.
    
  • Protege - An ontology editor from Stanford. Comes with an OWL plug-in (amongst other things).
    SWeDE is a semantic web development environment built on the Eclipse IDE.
    
  
  
• Commercial




• Unicorn have a commercial semantic offering they target as an entire architectural solution.
  
• SchemaLogic provide tools for enterprise vocabulary and taxonomy management.
  
• Network Inference provide a semantic web offering and ontology management.
  

Certainly semantic technology has yet to cross the chasm, but Early Adopters are obtaining value from the application of the new technologies and existing large corporations (both private and government) have been using elements of the semantic conceptual stack for many years.


from www.writersblock.ca/ summer1998/bookrev.htm

Key Lessons

Experience reports from ST 2005 suggest the following lessons:

• Starting Points
  
• Start small and focus on a specific business subject area.
  
• Roll out a vocabulary or taxonomy first and allow this to become bedded in. In particular, this approach does not require RDF or OWL adoption.
  
• Drive the semantic effort from EAI/EII initiatives to get good traction.
  
• Approaches
  


• ST 2005 practitioners are of the opinion that federated ontologies are good practice for large organisations. Organisations need to accept that they will end up with multiple overlapping ontologies. Provide high level upper ontologies to map these overlapping ontologies to and/or provide infrastructure for mapping between ontologies.
  
• Define vocabularies, taxonomies and ontologies from both top down and bottom up perspectives. It is important that a top down modeling activity provides broad shape to semantics work. However, a bottom up approach is required to make sure the semantic activities capture information as it is today. Defining a 'to-be' model without understanding the existing semantics of systems is not recommended by practitioners met at ST 2005.
  
• Examine the producing and consuming systems and ensure that the semantics of the existing models are captured in enough detail to validate any vocabulary work.
  
• Avoid attempting to build an enterprise ontology from the ground up. These tend to fail due to the time it take to build them and the federated nature of large organisations. Use integration driven vocabularies to drive out elements of the Enterprise data model piece by piece. Only the concepts shared between applications are in the model, but it is a significant improvement and it's an improvement that can happen in relatively simple stages.
  
• Leverage existing ontologies (such as those from XML standards bodies like OASIS).
  
• Governance
  
  
  
  • A vocabulary, taxonomy or ontology will need well defined governance and, in large organisations, a lightweight and nimble standards group to maintain the integrity of the system.
    
  • The UPS speaker (had a metadata repository that started in the 80's) recommend having a QA group responsible for the integrity of the models.
    
  • Control naming of data elements so they are inline with the vocabulary in the organisation. This allows schema (database or XML) to be reconciled back to the vocabulary.