Publish subscribe system based on ontology and XML filtering

Publish subscribe systems have received considerable attention during recent years. XML based publish-subscribe systems are on tremendous rise because of the properties of XML. But in order to accomplish the task filtering mechanism is required. Many filtering mechanisms exists such as XFilter, YFilter, AFilter etc, but most of these mechanisms do not filter the document for semantic matched information. M-Filter performs semantic matching of XML documents. But value-based predicates cannot be filtered by M-Filter. This paper proposes a technique which does semantic matching of XML data and also handles equality based value-based predicates. User Profiles are specified as XPath queries. A query node is checked in OWL classes, if a node is found it is returned with the matching results as well as with the semantically related data. Thus multiple queries are formed from a single subscription and these queries are then converted into twig patterns. On the other hand, XML document is parsed by DOM parser and a tree is built. Matching of twig nodes and the tree nodes takes place and only the matched information is displayed or delivered to the user.