QoSTalk : A Visual Quality of Service Programming and Development Environment

The provision of multimedia services is becoming ubiquitous. Services such as audio/video streaming, digital libraries and on-line businesses are widely deployed. Different middleware frameworks have been developed to enable such a dynamic and customized delivery of multimedia services. Two major types of QoS-aware systems have evolved:(1) Reservation-based Systems such as Qualman [3] and (2) Adaptation-based Systems such as Agilos [1]. However, both of them require applicationspecific Quality of Service(QoS) specifications such as configuration graphs, resource requirements and/or adaptation rules to be provided by the application developers or the users. In this paper, we present QoSTalk, a visual QoS programming and development framework, which allows us to visually program application specific QoS features at different granularity. It includes three major parts (1) Hierarchical Configuration Builder (2) QoS Documentation Template and (3) QoS Interpreter. The hierarchical configuration builder presents a set of visual tools for application developers. It allows the developer to depict all distributed components and their relations to generate the super configuration graph. We call it the super configuration graph because it includes a set of distinct configurations. Different configurations of the same application are related to different QoS levels. The visual tool consists of two component types: 1)composite components and 2) atomic components. The composite components may contain sub-components within themselves. There are four different kinds of links to represent four different relations between components: 1) data links ; 2) control links; 3) synchronization This work was supported by the National Science Foundation under contract number 9870736, the Air Force Grant under contract number F30602-97-2-0121, National Science Foundation Career Grant under contract number NSF CCR 96-23867, NSF PACI grant under contract number NSF PACI 1 1 13006, NSF CISE Infrastructure grant under contract number NSF EIA 99-72884, NSF CISE Infrastructure grant under contract number NSF CDA 96-24396, and NASA grant under contract number NASA NAG 2-1250.