Organizing and evaluating publish/subscribe systems with scopes

Modern applications and services need to process and respond to an ever growing number of internal and external events. In principle, publish/subscribe middleware would be the ideal platform for these event-driven applications, which range from the gathering of simple sensor data in ubiquitous environments up to the correlation and processing of complex events in business workflows. Most publish/subscribe middleware, however, offers no or just little support to adequately structure and organize network, services, and applications making it hard to deploy and adapt them in complex dynamic infrastructures. In this paper, we refine and concretize a scope concept for publish/subscribe systems to give application developers and system administrators powerful and effective means to organize these systems by controlling the visibility of events, subscriptions, and advertisements. Besides presenting the scope concept and discussing the integration into a middleware, our main contribution is a comprehensive evaluation based on the first publish/subscribe middleware prototype with integrated scoping. The evaluation analyzes the behavior a scoped publish/subscribe system in various settings and quantifies its benefits.