ProSem is a scalable wide-area publish/subscribe system that supports complex, stateful subscriptions as well as simple ones. A main feature of ProSem is its cost-based joint optimization of both subscription processing and notification dissemination.
To demonstrate how dissemination occurs and how various choices affect dissemination costs, I built the system visualization component for the ProSem System. A structure visualizer shows the network topology and routes chosen for dissemination. It also shows the traffic along overlay links and summary statistics for each broker. A time-series visualizer plots various performance metrics over time, including throughput, response time, and bandwidth consumption.