Journal ArticleDOI
Quality-of-service specification in distributed object systems
Svend Frolund,Jari Koistinen +1 more
TLDR
In this paper, the authors propose a general quality-of-service specification language, which they call QML, and extend UML, the de facto standard object-oriented modelling language, to support the concepts of QML.Abstract:
Traditional object-oriented design methods deal with the functional aspects of systems, but they do not address quality-of-service (QoS) aspects, such as reliability, availability, performance, security and timing. However, deciding which QoS properties should be provided by individual system components is an important part of the design process. Different decisions are likely to result in different component implementations and system structures. Thus, decisions about component-level QoS should commonly be made at design time, before the implementation is begun. Since these decisions are an important part of the design process, they should be captured as part of the design. We propose a general quality-of-service specification language, which we call QML. In this paper we show how QML can be used to capture QoS properties as part of designs. In addition, we extend UML, the de facto standard object-oriented modelling language, to support the concepts of QML. QML is designed to integrate with object-oriented features, such as interfaces, classes and inheritance. In particular, it allows specification of QoS properties through refinement of existing QoS specifications. Although we exemplify the use of QML to specify QoS properties within the categories of reliability and performance, QML can be used for specification within any QoS category - QoS categories are user-defined types in QML. Sometimes, QoS characteristics and requirements change dynamically due to changing user preferences, or changes in the environment. For such situations static specification is insufficient. To allow for dynamic systems that change and evolve over time, we provide a QoS specification runtime representation. This representation enables systems to create, manipulate and exchange QoS information, and thereby negotiate and adapt to changing QoS requirements and conditions.read more
Citations
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Journal ArticleDOI
A model for web services discovery with QoS
TL;DR: A new Web services discovery model is proposed in which the functional and non-functional requirements are taken into account for the service discovery and should give Web services consumers some confidence about the quality of service of the discovered Web services.
Modeling Quality of Service for Workflows and Web Service Processes
TL;DR: This paper presents a predictive QoS model that makes it possible to compute the quality of service for workflows automatically based on atomic task QoS attributes, and presents the implementation of the model for the METEOR workflow system.
Journal ArticleDOI
Quality of Service for Workflows and Web Service Processes
TL;DR: In this article, the authors present a predictive QoS model that makes it possible to compute the quality of service (QoS) for workflows automatically based on atomic task QoS attributes.
Book
Interval Neutrosophic Sets and Logic: Theory and Applications in Computing
TL;DR: This work defines the set-theoretic operators on an instance of a neutrosophic set, and calls it an Interval Neutrosophics Set (INS), and introduces a new logic system based on interval neutrosophile sets and proposed data model based on the extension of fuzzy data model and paraconsistent data model.
Object-Oriented Analysis and Design.
TL;DR: In this paper, the authors propose a separation of interface from implementation, which they call encapsulation, and demonstrate the advantages of rapid prototyping and graceful refinement of a class implementation.
References
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Transaction Processing: Concepts and Techniques
Jim Gray,Andreas Reuter +1 more
TL;DR: Using transactions as a unifying conceptual framework, the authors show how to build high-performance distributed systems and high-availability applications with finite budgets and risk.
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End-to-end arguments in system design
TL;DR: The end-to-end argument as discussed by the authors suggests that functions placed at low levels of a distributed computer system may be redundant or of little value when compared with the cost of providing them at that low level.
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TL;DR: A text on industrial system development using object- oriented techniques, rather than a book on object-oriented programming, will be useful to systems developers and those seeking a deeper understanding of object orientation as it relates to the development process.
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Understanding fault-tolerant distributed systems
TL;DR: This article attempts to introduce some discipline and order in understanding fault-tolerance issues in distributed system architectures by examining various proposals, discusses their relative merits, and illustrates their use in existing commercial fault-Tolerance systems.
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Object-oriented development: the fusion method
Derek Coleman,Patrick Simon Arnold,Stephanie Bodoff,Chris Dollin,Helena Gilchrist,Fiona Hayes,Paul Jeremaes +6 more
TL;DR: Fusion and Other Methods: Managing a Fusion Project, a Practical Guide to Analysis Models and Notations, and a Reference to Fusion Reference.