Overlay multicast for real-time distributed simulation

This dissertation is an investigation of overlay multicast services in support of distributed real-time virtual simulations over an open network environment. Overlay multicasting provides message relay services to support many-to-many communications in the very dynamic environment of distributed real-time virtual simulation.; This dissertation demonstrates that overlay multicast services is a viable mechanism to meet the demands of communications messaging far distributed real-time virtual simulation. A message traffic generator and test environment was developed for use in performance evaluation of a prototype protocol used to demonstrate feasibility far use of overlay multicast to support distributed real-time simulation.; An analytical model was developed to represent the message flow characteristics to determine the regions of feasibility for performance for overlay multicasting to support the target application environment. The analytical model was validated in laboratory measurements of the prototype and the results used to influence the design of the overlay protocol architecture.; Studies were conducted of live real-time distributed simulations operating in the laboratory and over the Defense Research and Engineering Network (DREN). Detailed studies and analysis of simulations in the laboratory were also conducted to help characterize the operating system performance that might be required to host the overlay protocol.; A proposed top-level architecture for the overlay protocol was developed based on key concepts identified in the laboratory performance studies, the analytical model, and the studies of live simulations. The proposed protocol is called the Extensible Modeling and Simulation Framework Overlay Multicast Protocol (XOM).