-
02/2013;
-
[show abstract]
[hide abstract]
ABSTRACT: Virtual collaboration among geographically dispersed resources, groups or organizational units requires support from their environment. The establishment, management and exploitation of dynamic, cross-organizational sharing relationship require new technology, which is independent of any proprietary technology and have backing of mainstream development and research institutes. This paper critically compares two peer-to-peer (P2P) protocols i.e. JXTA and Web services resource framework (WSRF) with respect to their effectiveness for virtual collaboration. The comparison is based on our experiences of developing a prototype for virtual organization. This paper is result of out going research to build community for efficient resource discovery.
Cluster Computing and the Grid, 2007. CCGRID 2007. Seventh IEEE International Symposium on; 06/2007
-
Concurrency and Computation: Practice and Experience. 01/2007; 19:1633-1641.
-
[show abstract]
[hide abstract]
ABSTRACT: We investigate the requirements of Scientific Workflows in context of the Business Process Execution Language for Web Services (BPEL4WS/ BPEL. The complexity, unpredictability and inter-dependency of the components in a scientific workflow often demand flexibility in a workflowlanguage in order to support; 1) exception handling, 2) recovery from uncertain situations, 3) user interactions to facilitate interactive steering and monitoring, 4) dynamism to adapt to the changing environment, 5) compensation handling to roll back, and 6) support for dynamic selection of services. We illustrate these requirements with examples taken from a real scientific workflow; the e-HTPX project for high throughput protein crystallography. In this paper, we discuss the application of BPEL, which is widely regarded as the de-facto standard for orchestrating Web Services for Business Workflows with a large set of features to support complex requirements. These features, along with other standard tools, can be adapted to fulfill the requirements of Scientific Workflows.
Cluster Computing and the Grid, 2006. CCGRID 06. Sixth IEEE International Symposium on; 06/2006
-
[show abstract]
[hide abstract]
ABSTRACT: The organization of resources/peers in communities is suggested to be an efficient way for resource discovery, but effectiveness of proposed communities depends on the active role and responsibility of a "community coordinator". Communities are pools of diverse peers/services sharing and controlling resources and which have "agreed" to co-operate to enhance their usability; such co-operation needs coordination mechanism, negotiated policies, monitoring and leadership to re-solve disputes. In this paper we will outline the role of a community coordinator to sustain the effective working of the community and to provide the general framework for community formation. This work is related to our previous and on going work on "community formation " [1] and [2]. Main focus of this paper is to address expectations from the coordinator along with its responsibilities and capabilities.
Semantics, Knowledge and Grid, 2005. SKG '05. First International Conference on; 12/2005
-
-
[show abstract]
[hide abstract]
ABSTRACT: A Web based portal acting as a presentation layer to the Grid has a special meaning by providing transparent access to Grid resources. Based on our experience in Grid portal development there is a need to draw a clear picture from the height of the architecture level. In this paper, this is defined based on the most important part of the J2EE architecture Enterprise JavaBeans, which makes a clear separation between the presentation, business logic and data layers. Additional benefit comes with J2EE 1.4 makes the component-oriented architecture easily converted to service-oriented architecture by exposing stateless session beans as Web services. Poster at GCE 05: Grid Portals Workshop, held in conjunction with SC|05, 18 November 2005, Seattle, USA
-
[show abstract]
[hide abstract]
ABSTRACT: We investigate the requirements of Scientific Workflows in context of the Business Process Execution Language for Web Services (BPEL4WS/ BPEL. The complexity, unpredictability and inter-dependency of the components in a scientific workflow often demand flexibility in a workflow-language in order to support; 1) exception handling, 2) recovery from uncertain situations, 3) user interactions to facilitate interactive steering and monitoring, 4) dynamism to adapt to the changing environment, 5) compensation handling to roll back, and 6) support for dynamic selection of services. We illustrate these requirements with examples taken from a real scientific workflow; the e-HTPX project for high throughput protein crystallography. In this paper, we discuss the application of BPEL, which is widely regarded as the de-facto standard for orchestrating Web Services for Business Workflows with a large set of features to support complex requirements. These features, along with other standard tools, can be adapted to fulfill the requirements of Scientific Workflows.
-
[show abstract]
[hide abstract]
ABSTRACT: The CCLRC e-Science Centre is working on a number of UK e-Research projects supporting access to large research facilities such as the neutron spallation source (ISIS), the Synchrotron Radiation Source (SRS) and the Central Laser Facility (CLF) and the new synchroton light source, Diamond in addition to the National Grid Service and the HPCx supercomputing facility. The aim of this work is to create an Integrated e-Science Environment for CCLRC. A clear requirement of facility users is to provide seamless access and integration of these resources. This can be done by developing portal interfaces for each facility or project exposing their services as portlets for reuse between the different portal frameworks and CCLRC projects. This paper outlines the benefit of using portal frameworks and portlets to meet this goal with a Service Oriented Architecture designed to complement desktop tools. An example is given of the portal services being provided for the National Grid Service (NGS) and e-HTPX portals, which include computational and data Grid production resources for research.
-
[show abstract]
[hide abstract]
ABSTRACT: The emergence of portal technology is providing benefits in developing portlet interfaces to applications to meet the current and future requirements of CCLRC facilities support. Portlets can be reused by different projects, e.g. the high-profile Integrative Biology project (with the University of Oxford), and in different Java Specification Request 168 Portlet Specification (JSR 168) compliant portal frameworks. Deployment and maintenance of applications developed as portlets becomes easier and manageable. A community process is already beginning and many portal frameworks come with free-to-use useful portlets. As rendering is carried out in the framework, applications can be easily accessible and internationalized. Portlets are compatible with J2EE, thus providing additional capabilities required in the service-oriented architecture (SOA). We also describe how Web service gateways can be used to provide many of the functionalities encapsulated in a portal server in a way to support Grid applications. Portals used as a rich client can allow users to customize or personalize their user interfaces and even their workflow and application access. CCLRC facilities will be able to leverage the work so far carried out on the National Grid Service (NGS) and e-HTPX portals, as they are fully functional and have received detailed user feedback. This demonstrates the usefulness of providing advanced capabilities for e-Research and having the associated business logic in a SOA loosely coupled from the presentation layer for an Integrated e-Science Environment. Concurrency and Computation: Pract. Exper. 2007; 19:751-766 (Special issue on Science Gateways)
-
[show abstract]
[hide abstract]
ABSTRACT: This paper presents a workflow portal for Grid applications; which supports different workflow languages and workflow optimisation. We present an XSLT converter that converts from one workflow language to another and enables the interoperation between different workflow languages. We discuss strategies for choosing the optimal service from several semantically-equivalent Web services in a Grid application. The dynamic selection of Web services involves discovering a set of semantically equivalent services by filtering available services based on metadata, and selecting an optimal service based on real-time data and/ or historical data recorded during prior executions. Finally we describe the framework and implementation of the workflow portal which aggregates different components of the project using Java portlets.
-
-
[show abstract]
[hide abstract]
ABSTRACT: A Web-based portal acting as a presentation layer to the Grid allows us to provide a transparent means of access to Grid resources. Our previous experiences in developing Grid portals have shown that there is a need to draw a clear high-level picture of the architecture. This could be defined using the J2EE component-oriented architecture, which enables a clear separation between the presentation, business logic and data layers. Additional benefits come with J2EE 1.4 making it possible to build up advanced service-based Grid portals by exposing stateless session beans as Web services. In this paper, lessons learnt from our prototype portal/portlet development using Enterprise JavaBeans (EJB) are reported. Copyright © 2007 John Wiley & Sons, Ltd.
-
[show abstract]
[hide abstract]
ABSTRACT: Locating suitable resources within a Grid system is a computationally intensive process, with no guarantee of quality and suitability of the discovered resources. An alternative approach is to categorize resources based on the services they provide leading to the interaction of peers with common goals to form societies/communities. Organization of resources in different communities is suggested to be useful for efficient resource discovery. We have implemented JXTA prototype to illustrate the concepts of community formation in which Peers offering different services can be grouped together based on different criteria. http://csdl2.computer.org/persagen/DLAbsToc.jsp?resourcePath=/dl/proceedings/&toc=comp/proceedings/skg/2006/2673/00/2673toc.xml&DOI=10.1109/SKG.2006.68
-
[show abstract]
[hide abstract]
ABSTRACT: We provide a critical evaluation of the different Web Service styles and approaches to data-binding and validation for use in data-centric scientific applications citing examples and recommendations based on our experiences. The current SOAP APIs for Java are examined, including the Java API for XML-based remote procedure calls (JAX-RPC) and Document style messaging. We assess the advantages and disadvantages of 'loose' verses 'tight' data binding and outline some best practices for WSDL development. For the most part, we recommend the use of the document/ wrapped style with a 100% XML schema compliant data-model that can be separated from the WSDL definitions. We found that this encouraged collaboration between the different partners involved in the data model design process and assured interoperability. This also leverages the advanced capabilities of XML schema for precisely constraining complex scientific data when compared to RPC and SOAP encoding styles. We further recommend the use of external data binding and validation frameworks which provide greater functionality when compared to those in-built within a SOAP engine. By adhering to these best practices, we identified important variations in client and experimental data requirements across different institutions involved with a typical e-Science project.
-
[show abstract]
[hide abstract]
ABSTRACT: This paper presents a workflow portal for Grid applications; which supports different workflow languages and workflow optimisation. We present an XSLT converter that converts from one workflow language to another and enables the interoperation between different workflow languages. We discuss strategies for choosing the optimal service from several semantically-equivalent Web services in a Grid application. The dynamic selection of Web services involves discovering a set of semantically equivalent services by filtering available services based on metadata, and selecting an optimal service based on real-time data and/ or historical data recorded during prior executions. Finally we describe the framework and implementation of the workflow portal which aggregates different components of the project using Java portlets. June 2007
-
-
[show abstract]
[hide abstract]
ABSTRACT: The organization of resources in communities is an efficient way for resource discovery. The effectiveness of proposed communities depends on the technologies selected, their interoperability, platform independence and compliance with standards. This paper outlines the role of different available technologies to sustain the effective working of the community and to provide the general middleware for the community formation. Main focus of this paper is to evaluate the Web Services related specifications particularly Web Services Resource Framework and Web Services Distributed Management; and their effectiveness in the community formation.
-
[show abstract]
[hide abstract]
ABSTRACT: This paper gives a description of building a Grid portal infrastructure in CCLRC to allow computational scientists, researchers and application users' access to resources via an easy to use web based portal interfaces. The goal is to develop common grid application components that can be used by portal developers and administrators to build and deploy on portal frameworks. This will allow users to authenticate securely to remote resources and provide transparent access to Grid related tools to manage their task efficiently. The current portal technology, JSR 168, will be described and the development of Java based Grid applications. The work will be substantiated by giving an example of building the UK e-Science National Grid Service (NGS) portal.
-
