Resilient and Efficient Delivery over Message Oriented Middleware.

PhDThe publish/subscribe paradigm is used to support a many-to-many model that allows an efficient dissemination of messages across a distributed system. Message Oriented Middleware (MOM) is a middleware that provides an asynchronous method of passing information between networked applications. MOMs can be based on a publish/subscribe model, which offers a robust paradigm for message delivery. This research is concerned with this specific type of MOM. Recently, systems using MOMs have been used to integrate enterprise systems over geographically distributed areas, like the ones used in financial services, telecommunication applications, transportation and health-care systems. However, the reliability of a MOM system must be verified and consideration given to reachability to all intended destinations typically with to guarantees of delivery. The research in this thesis provides an automated means of checking the (re)configuration of a publish/subscribe MOM system by building a model and using Linear-time Temporal Logic and Computation Tree Logic rules to verify certain constraints. The verification includes the checking of the reachability of different topics, the rules for regulating the working of the system, and checking the configuration and reconfiguration after a failure. The novelty of this work is the creation and the optimization of a symbolic model checker that abstracts the end-to-end network configuration and reconfiguration behaviour and using it to verify reachability and loop detection. In addition a GUI interface, a code generator and a sub-paths detector are implemented to make the system checking more user-friendly and efficient. The research then explores another aspect of reliability. The requirements of mission critical service delivery over a MOM infrastructure is considered and we propose a new way of supporting rapid recovery from failures using pre-calculated routing Abstract tables and coloured flows that can operate across multiple Autonomous System domains. The approach is critically appraised in relation to other published schemes