QoSTalk : A Visual Quality of Service Programming and Development Environment Xiaohui Gu,Dongyan Xu,Duangdao Wichadakul, Klara Nahrstedt Department of Computer Science University of Illinois at Urbana-Champaign Urbana, IL 61801 Email:fxgu, d-xu, wichadak ,
[email protected] July 27, 2000
Abstract 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.
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links; 4) attachment links. To facilitate QoS specifications for both the configuration graphs and individual components of distributed component-based systems, we have designed a general Hierarchical Quality of service Modeling Language(HQML) which is an extended version of HTML and a subclass of XML. The QoS Documentation Template is a HQML file template which is generated automatically after application developers set up a possible application configuration. The QoS Documentation Template is a partially completed HQML file which already specifies the relations between different components and the hierarchical structures of the composite components. The application developer can fill in all kinds of application specific QoS specifications for both the overall configuration and the individual components. The QoS Interpreter translates the HQML file into the QoS profile which is needed by the underlying distributed middleware framework. During the runtime, the underlying middleware instantiates the distributed components and enforces the delivery of the Quality of Service according to the information saved in the QoS profile[2]. We prototype QoSTalk in Java and our case studies with serval distributed multi-media applications such as the Video conference, OmniTrack Visual tracking , and Web-based Shopping mall provide sound verifications that QoSTalk effectively fills the gap for an application developer between the very general QoS management provided by the distributed middleware and different kinds of distributed multi-media applications.
References [1] B.Li and K.Nahrstedt. A control-based middleware framework for quality of service adaptation. IEEE Journal on Selected Areas in Communication, September 1999. [2] K.Nahrstedt, Duangdao Wichadakul, and Dongyan Xu. Distributed QoS Compilation and Runtime Instantiation. Proceedings of IEEE/IFIP International Workshop on QoS 2000 (IWQoS2000), June 2000. [3] K. Nahrstedt, H. Chu, and S. Narayan.
QoS-Aware Resource Management for Distributed Multi-media
Applications. Journal on High-Speed Networking, Special Issue on Multimedia Networking, 8, 1998.
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