An Ontology-Based Publish/Subscribe System

Wang, Jin, Li

semanticweb publish subscribe pub/sub ontology dissemination

@inproceedings{wang:middleware-2004,
  author = {Jinling Wang and Beihong Jun and Jing Li},
  title = {An Ontology-Based Publish/Subscribe System},
  booktitle = {International Middleware Conference},
  address={Toronto, Canada},
  year = {2004},
  pages = {232--253}
}

Trying to balance expressiveness and efficiency

• "Should support events in different formats and semantics"
• Most systems use either relational or tree structures, but it may be useful to use more generic graph structures

In this work subscription are represented as graph patterns; notifications are in RDF

• Places some severe restrictions on the graph model
  • One and only one home vertex (the event object)
  • Graph has a single component, all nodes are reachable from the home vertex (remember that it's directed, so this is not trivial)
• Uses a funky language developed in the paper for describing the match pattern

The home vertex and reachability requirements are key, as they enable a reasonably straightforward matching process on incoming events

• Grab by home vertex, then breadth-first compare to compiled subscriptions

No mention is made of inference or actually using ontologies

• Seeming all that means here is encoding notifications in RDF