M. G. Polan

Bio: M. G. Polan is an academic researcher from IBM. The author has contributed to research in topics: Differentiated service & Service level objective. The author has an hindex of 2, co-authored 2 publications receiving 335 citations.

Web services on demand: WSLA-driven automated management

Abstract: In this paper we describe a framework for providing customers of Web services differentiated levels of service through the use of automated management and service level agreements (SLAs). The framework comprises the Web Service Level Agreement (WSLA) language, designed to specify SLAs in a flexible and individualized way, a system to provision resources based on service level objectives, a workload management system that prioritizes requests according to the associated SLAs, and a system to monitor compliance with the SLA. This framework was implemented as the utility computing services part of the IBM Emerging Technologies Tool Kit, which is publicly available on the IBM alphaWorksTM Web site.

Technical note: using the San Francisco frameworks with visualage for Java

Abstract: This technical note describes the advantages of using the VisualAgeTM for JavaTM (VAJ) integrated development environment when working with the IBM San FranciscoTM frameworks. It also discusses minimum system requirements, how to get started, and tips for using VAJ to exploit the frameworks. To fully utilize the material, the reader should be familiar with Java programming and with the basic concepts of integrated development environments.

Service oriented architectures: approaches, technologies and research issues

Abstract: Service-oriented architectures (SOA) is an emerging approach that addresses the requirements of loosely coupled, standards-based, and protocol- independent distributed computing. Typically business operations running in an SOA comprise a number of invocations of these different components, often in an event-driven or asynchronous fashion that reflects the underlying business process needs. To build an SOA a highly distributable communications and integration backbone is required. This functionality is provided by the Enterprise Service Bus (ESB) that is an integration platform that utilizes Web services standards to support a wide variety of communications patterns over multiple transport protocols and deliver value-added capabilities for SOA applications. This paper reviews technologies and approaches that unify the principles and concepts of SOA with those of event-based programing. The paper also focuses on the ESB and describes a range of functions that are designed to offer a manageable, standards-based SOA backbone that extends middleware functionality throughout by connecting heterogeneous components and systems and offers integration services. Finally, the paper proposes an approach to extend the conventional SOA to cater for essential ESB requirements that include capabilities such as service orchestration, "intelligent" routing, provisioning, integrity and security of message as well as service management. The layers in this extended SOA, in short xSOA, are used to classify research issues and current research activities.

Dynamic QoS Management and Optimization in Service-Based Systems

Abstract: Service-based systems that are dynamically composed at runtime to provide complex, adaptive functionality are currently one of the main development paradigms in software engineering. However, the Quality of Service (QoS) delivered by these systems remains an important concern, and needs to be managed in an equally adaptive and predictable way. To address this need, we introduce a novel, tool-supported framework for the development of adaptive service-based systems called QoSMOS (QoS Management and Optimization of Service-based systems). QoSMOS can be used to develop service-based systems that achieve their QoS requirements through dynamically adapting to changes in the system state, environment, and workload. QoSMOS service-based systems translate high-level QoS requirements specified by their administrators into probabilistic temporal logic formulae, which are then formally and automatically analyzed to identify and enforce optimal system configurations. The QoSMOS self-adaptation mechanism can handle reliability and performance-related QoS requirements, and can be integrated into newly developed solutions or legacy systems. The effectiveness and scalability of the approach are validated using simulations and a set of experiments based on an implementation of an adaptive service-based system for remote medical assistance.

Service-Oriented Computing

Abstract: Service-Oriented Computing (SOC) promises a world of cooperating services loosely connected, creating dynamic business processes and agile applications that span organizations and platforms. As a computing paradigm, it utilizes services as fundamental elements to support rapid, low-cost development of distributed applications in heterogeneous environments. Realizing the SOC promise requires the design of Service-Oriented Architectures (SOAs) that enable the development of simpler and cheaper distributed applications. In this collection, researchers from academia and industry report on recent advances in the field, exploring approaches, technology, and research issues related to developing SOAs.SOA enables service discovery, integration, and use, allowing application developers to overcome many distributed enterprise computing challenges. The contributors to this volume treat topics related to SOA and such proposed enhancements to it as Event Drive Architecture (EDA) and extended SOA (xSOA) as well as engineering aspects of SOA-based applications. In particular, the chapters discuss modeling of SOA-based applications, SOA architecture design, business process management, transactional integrity, quality of service (QoS) and service agreements, service requirements engineering, reuse, and adaptation.Contributors: L. Bahler, Boualem Benatallah, Christoph Bussler, F. Caruso, Fabio Casati, C. Chung, Emilia Cimpian, B. Falchuk, Dimitrios Georgakopoulos, Jaap Gordijn, Paul Grefen, Jonas Grundler, Woralak Kongdenfha, Yutu Liu, Mark Little, Heiko Ludwig, J. Micallef, Thomas Mikalsen, Adrian Mocan, Anne H. H. Ngu, Bart Orriens, Savas Parastatidis, Michael Papazoglou, Barbara Pernici, Pierluigi Plebani, Isabelle Rouvellou, Quan Z. Sheng, Halvard Skogsrud, Stefan Tai, Farouk Toumani, Pascal van Eck, Jim Webber, Roel Wieringa, Jian Yang, Liangzhao Zeng, Olaf Zimmermann.Cooperative Information Systems series

Service selection algorithms for composing complex services with multiple qos constraints

Abstract: One of the promises of the service-oriented architecture (SOA) is that complex services can be composed using individual services. Individual services can be selected and integrated either statically or dynamically based on the service functionalities and performance constraints. For many distributed applications, the runtime performance (e.g. end-to-end delay, cost, reliability and availability) of complex services are very important. In our earlier work, we have studied the service selection problem for complex services with only one QoS constraint. This paper extends the service selection problem to multiple QoS constraints. The problem can be modelled in two ways: the combinatorial model and the graph model. The combinatorial model defines the problem as the multi-dimension multi-choice 0-1 knapsack problem (MMKP). The graph model defines the problem as the multi-constraint optimal path (MCOP) problem. We propose algorithms for both models and study their performances by test cases. We also compare the pros & cons between the two models.