Patent ID: 8112416

Claim:
A semantic publish-subscribe system, comprising: a plurality of subscribers; a plurality of publishers; and a server that includes a memory device for storing a program and a processor in communication with the memory device, wherein the server receives and stores subscriptions that are described in web ontology language (OWL) graph patterns from the plurality of subscribers and receives events that are described in semantic graphs formed by OWL assertions from the plurality of publishers, wherein when the server receives an event from a publisher, the server expands the OWL assertions of the event using a reasoner to produce an expanded event, the server matches the expanded event to a subscription, and then, the server notifies a subscriber whose interest matches the event, and wherein the subscriptions are stored in a linked-chains structure by, creating a chain of nodes for each subscription, wherein for each subscription each node in the chain of nodes represents a triple pattern in the subscription; arranging the nodes in each chain of nodes in a decreasing order of selectivity, wherein nodes that are in different chains or the same chain are linked to each other if their triple patterns are equivalent; and inserting the chain of nodes for each subscription into a queue by using a chain ordering algorithm.