QoS Control by Balancing Continuous MM Streams

摘要

Loosely coupled systems, i.e. distributed systems that have to execute a common task obviously need some type of end-to-end control. End-to-end control will be achieved by sensoring relevant system variables and by controlling the feeding input components. Whereas sensoring is a continuous activity, controlling in most cases is a discrete one. Discrete controlling signals will be issued when certain invariant conditions of the system get violated. Models of which obey the components of a continuously operating system, a continuously sensoring component and a discretely decision-taking component. In order to achieve an adequate view it is envisaged to combine modelling concepts that represent the continuous system behaviour with those for discrete decision-taking and for steering the stream sources. Decision-taking and controlling is represented by so-called hybrid systems. The system behaviour itself is modelled by continuous streams. Hybrid systems are a combination of state machines together with continuously evolving variables. The continuous stream model is based on differential equations.