Quality of Service--Aware Distributed Object Systems

QoS-specification, QoS-enabled trading, distributed object systems, object component specification, object interoperability, quality of service, object-oriented programming Computing systems deliver their functionality at a certain level of performance, reliability, and security. We refer to such nonfunctional aspects as quality-of-service (QoS) aspects. Delivering a satisfactory level of QoS is very challenging for systems that operate in open, resource varying environments such as the Internet or corporate intranets. A system that operates in an open environment may rely on services that are deployed under the control of a different organization, and it cannot per se make assumptions about the QoS delivered by such services. Furthermore, since resources vary, a system cannot be built to operate with a fixed level of available resources. To deliver satisfactory QoS in the context of external services and varying resources, a system must be QoS aware so that it can communicate its QoS expectations to those external services, monitor actual QoS based on currently available resources, and adapt to changes in available resources.