Formalizing Multimedia QoS Constraints Using Actors

The vision of future information systems is that different forms of information are potentially accessible at anytime through the Internet. We describe challenges in the modeling and specification of timing related multimedia (MM) services in open distributed systems. Management of multimedia services in an open system is complicated by the heterogeneity of application requirements, multimedia information, and system components. Services and systems in this environment evolve dynamically and their components interact with an environment that is not under their control. We propose a formal specification of timing related Quality-of-Service (QoS) attributes in an actor-based distributed system and describe some techniques for informally reasoning about quantitative QoS properties. Keywords QoS, Real-time, Multimedia, Actors, Concurrency semantics, Sessions 1 MOTIVATION Services and systems in a global information environment like the WWW evolve dynamically and their components interact..