Maintaining Publish/Subscribe Middleware QoS in Dynamic Environments

Quality of service (QoS)-enabled publish/subscribe (pub/sub) middleware provides powerful support for data dissemination. It is hard, however, to maintain specified QoS properties (such as reliability and latency) in dynamic environments (such as disaster relief operations or power grids). For example, managing QoS manually is often not feasible in dynamic systems due to slow human response times and the complexity of managing multiple interrelated QoS settings. Autonomic adaptation provides a promising approach to maintaining QoS properties of QoS-enabled pub/sub middleware in dynamic environments. By monitoring key system resources and environment aspects, changes to middleware mechanisms (e.g., associations of publishers and subscribers to transport protocols) can be made autonomically to maintain specified QoS. This paper describes the research we are conducting on highly configurable QoS-enabled middleware, adaptive transport protocols, system monitoring, supervised machine learning techniques, and autonomic adaptation to maintain specified QoS as the system environment and configuration dynamically changes.