Efficient Matching of Events in Distributed Middleware Systems

Increasingly interactions which entities have with each other are network bound. The entities, with which applications andservices need to interact, span a wide spectrum that includes desktops, PDAs, appliances, and other networked resources. These events encapsulate information pertaining to transactions, data interchange, system conditions and finally the search, discoveryand subsequent sharing of resources. Events have internal or external (system computed) destinations associated with them. In the case of search, discovery and publish/subscribe interactions the system has to efficiently calculate destinations from the corresponding events. This computing of destinations is referred to as matching and is, in itself, a distributed process, which operates on the distributed management of client interests (advertisements and subscriptions). The distributed nature of the underlying messaging infrastructure also mandates an efficient routing engine. Inefficient approaches to either the calculation of, or routing to, destinations can result in unacceptable network degradations. In this paper we explore matching, routing and network utilization issues in the context of NaradaBrokering, which provides support for centralized, distributed and P2P interactions. We also discuss the implications, and include results, pertaining to the different matching engines supported within the NaradaBrokering system.