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Enhancing Scientific Workflows with Secure Shell Functionality in UNICORE Grids
Abstract
The UNICORE grid technology provides a seamless, secure and intuitive access to distributed grid resources such as computational or storage related resources. In addition, its extensible character through application-specific plug-ins and its enhancements developed in various European-funded projects leads to the UNICORE technology that is used in daily production at many supercomputer centers and research facilities world-wide today. In this paper we present an enhancement that provides the dynamic capabilities of a secure shell terminal within the UNICORE grid technology while single sign-on remains. This enhancement allows the integration of the dynamic work-behavior of scientists, or existing scientific applications, to be more integrated into the usual workflow with UNICORE and therefore in collaborative grid environments. As a well-known tool in the scientific community, a secure shell terminal provides the most flexible way of working on remote systems that no graphical user interface or advanced tooling in grid computing can ever provide.
... There are also various implementations of workflow engines on the Grid. Examples are ASKALON [14], Unicore [15], Kepler [16], GridAnt [17], Pegasus [18], and GridFlow [19]. An overview of these workflow systems is presented in [20]. ...
This work developed a workflow engine that enables the execution of workflows on existing Cloud platforms. The workflow engine automatically delivers the computation of each individual task to the selected Cloud and transfers the input/output data across different platforms. Additionally, it predicts the execution time and payment of the tasks, helping users select the best Cloud services with respect to the performance vs. cost tradeoff.
... In more detail, a dedicated COVS framework-specific client plugin (e.g. COVS GridBean) is responsible for that following the mechanisms as described in [7]. ...
Today's large-scale scientific research often relies on the collaborative use of a Grid or c-Science infrastructure (e.g. DEISA, EGEE, TeraGrid, OSG) with computational, storage, or other types of physical resources. One of the goals of these emerging infrastructures is to support the work of scientists with advanced problem-solving tools. Many e-Science applications within these infrastructures aim at simulations of a scientific problem on powerful parallel computing resources. Typically, a researcher first performs a simulation for some fixed amount of time and then analyses results in a separate post-processing step, for instance, by viewing results in visualizations. In earlier work we have described early prototypes of a Collaborative Online Visualization and Steering (COVS) Framework in Grids that performs both -simulation and visualization -at the same time (online) to increase the efficiency of e-Scientists. This paper evaluates the evolved mature reference implementation of the COVS framework design that is ready for production usage within Web service-based Grid and e-Science infrastructures.
This article presents a research concerning password management and single sign-on for accessing Internet applications. Many Internet applications require users to subscribe to their services and authenticate themselves through the use of login credentials. The number of such applications is increasing exponentially, which caused ineffective login credential management among users. This study was conducted with two objectives (i) to identify how users manage their usernames and passwords and (ii) to examine whether users see the benefits of single sign-on. To achieve these objectives, a focus group interview was conducted on students from a local university. The results of the study suggested that the students did not practise proper password management. Further, it suggested that single sign-on may not be the immediate solution to improve the students’ password management.
Many production e-Science infrastructures (e.g. DEISA, D-Grid) have begun to offer a wide variety of services for end-users during the past several years. Many e-Scientists solve their scientific problems by us-ing parallel computing applications on clusters and collaborative on-line visualization and steering (COVS) is known as a tool for analyz-ing and better understanding of these applications. In absence of a widely accepted COVS framework within Grids, visualizations are often created using proprietary technologies assuming a dedicated scenario. This makes it feasible to analyze the usual requirements to provide a blueprint for a more general COVS framework that can be integrated into Grid middleware systems such as UNICORE, gLite, or Globus Toolkits. These requirements lead to a design that was successfully implemented as a higher-level service in UNICORE and presented at numerous places such as the Open Grid Forum 19 and 20, Europar 2006, Supercomputing 2006 and DEISA trainings.
started. The goal was to provide users of the German supercomputer centers with a seam- less, secure, and intuitive access to the heterogeneous computing resources at the centers consistent with the recommendations of the German Science Council 2 . A first prototype was developed in project UNICORE 3 to demonstrate the concept. The current production version was created in a follow-on project UNICORE Plus 4 which was completed in 2002. UNICORE's scope is expanded in projects like EUROGRID 5 , GRIP 6 and OpenMolGRID 7 to provide support for additional application areas and fun ctions like resource brokering. Section 2 familiarises the term Grid and illustrates its maj or ideas and concepts. UNI- CORE as a realization of these ideas is introduced in Section 3 followed by a detailed description of the benefits UNICORE offers to users and appli cation developers. Section 5 summarizes the paper and concludes with an outlook.
Nearly all existing HPC systems are operated by resource management systems based on the queuing approach. With the increasing acceptance of grid middleware like Globus, new requirements for the underlying local resource management systems arise. Features like advanced reservation or quality of service are needed to implement high level functions like co-allocation. However it is difficult to realize these features with a resource management system based on the queuing concept since it considers only the present resource usage.
In this paper we present an approach which closes this gap. By assigning start times to each resource request, a complete schedule is planned. Advanced reservations are now easily possible. Based on this planning approach functions like diffuse requests, automatic duration extension, or service level agreements are described. We think they are useful to increase the usability, acceptance and performance of HPC machines. In the second part of this paper we present a planning based resource management system which already covers some of the mentioned features.
This document defines a binding for a SOAP 1.1 message to be carried within a MIME multipart/related message in such a way that the processing rules for the SOAP 1.1 message are preserved. The MIME multipart mechanism for encapsulation of compound documents can be used to bundle entities related to the SOAP 1.1 message such as attachments. Rules for the usage of URI references to refer to entities bundled within the MIME package are specified.
"Grid" computing has emerged as an important new field, distinguished from conventional distributed computing by its focus on large-scale resource sharing, innovative applications, and, in some cases, high-performance orientation. In this article, we define this new field. First, we review the "Grid problem," which we define as flexible, secure, coordinated resource sharing among dynamic collections of individuals, institutions, and resources-what we refer to as virtual organizations. In such settings, we encounter unique authentication, authorization, resource access, resource discovery, and other challenges. It is this class of problem that is addressed by Grid technologies. Next, we present an extensible and open Grid architecture, in which protocols, services, application programming interfaces, and software development kits are categorized according to their roles in enabling resource sharing. We describe requirements that we believe any such mechanisms must satisfy, and we discuss the central role played by the intergrid protocols that enable interoperability among different Grid systems. Finally, we discuss how Grid technologies relate to other contemporary technologies, including enterprise integration, application service provider, storage service provider, and peer-to-peer computing. We maintain that Grid concepts and technologies complement and have much to contribute to these other approaches.
The UNICORE (UNiform Interface to COmputing REsources) software provides a Grid infrastructure together with a computing portal for engineers and scientists to access supercomputer centres from anywhere on the Internet. While UNICORE is primarily designed for the submission and control of batch jobs, it is also feasible to establish an on-line connection between an application and the UNICORE user-client. This opens up the possibility of performing on-line visualization and computational steering of applications under UNICORE control while maintaining the security provided by this system. This contribution describes the design of a steering extension to UNICORE based on the steering toolkit VISIT (VISualization Interface Toolkit). VISIT is a lightweight library that supports bidirectional data exchange between visualizations and parallel applications. As an example application, a parallel simulation of a laser-plasma interaction that can be steered by an AVS/Express application is presented.
"Grid" computing has emerged as an important new field, distinguished from conventional distributed computing by its focus on large-scale resource sharing, innovative applications, and, in some cases, high-performance orientation. In this article, we define this new field. First, we review the "Grid problem," which we define as flexible, secure, coordinated resource sharing among dynamic collections of individuals, institutions, and resources-what we refer to as virtual organizations. In such settings, we encounter unique authentication, authorization, resource access, resource discovery, and other challenges. It is this class of problem that is addressed by Grid technologies. Next, we present an extensible and open Grid architecture, in which protocols, services, application programming interfaces, and software development kits are categorized according to their roles in enabling resource sharing. We describe requirements that we believe any such mechanisms must satisfy, and we discuss the central role played by the intergrid protocols that enable interoperability among different Grid systems. Finally, we discuss how Grid technologies relate to other contemporary technologies, including enterprise integration, application service provider, storage service provider, and peer-to-peer computing. We maintain that Grid concepts and technologies complement and have much to contribute to these other approaches.
Nearly all existing HPC systems are operated by resource management,systems based on the queuing approach. With the increasing acceptance of grid middleware like Globus, new requirements for the underlying local resource management,systems arise. Features like advanced reservation or quality of service are needed to implement,high level functions like co-allocation. However it is dicult,to realize these features with a resource management,system based on the queuing concept since it considers only the present resource usage. In this paper we present an approach which closes this gap. By assigning start times to each resource request, a complete schedule is planned. Advanced reservations are now,easily possible. Based on this planning approach functions like diuse requests, automatic duration extension, or service level agreements are described. We think they are useful to increase the usability, acceptance and performance of HPC machines. In the second part of this paper we present a planning based resource management system which already covers some of the mentioned features.
The UNICORE Grid system implements a vertically integrated Grid architecture providing seamless access to resources within difierent or- ganizations. The software is developed and deployed by companies, re- search - and computing centres and projects throughout Europe. The UNICORE Forum (1) promotes the UNICORE software and interfaces, and makes it available for download. In this paper we instance UNI- CORE for the evolution of a Grid system towards a service-oriented Grid, primarily focussing on architectural concepts and models. Based on the current architecture and the enhancements provided by the project GRIP (2), we depict flrst steps already taken to integrate Web - and Grid Services into UNICORE. This includes provision of OGSI- compliant portTypes (3) parallel to the proprietary interfaces as well as the design of XML-based protocols. Furthermore we present the roadmap deflned by GRIP to achieve a consistent development towards an OGSA (4) implementation.
IntroductionThe Need for Grid TechnologiesBackground
An Open Grid Services ArchitectureApplication ExampleTechnical DetailsNetwork Protocol BindingsHigher-level ServicesRelated WorkSummaryAcknowledgmentsReferences
The UNICORE Grid-technology provides a seamless, secure and intuitive access to distributed Grid resources. In this paper we present the recent evolution from project results to production Grids. At the beginning UNICORE was developed as a prototype software in two projects funded by the German research ministry (BMBF). Over the following years, in various European-funded projects, UNICORE evolved to a full-grown and well-tested Grid middleware system, which today is used in daily production at many supercomputing centers worldwide. Beyond this production usage, the UNICORE technology serves as a solid basis in many European and International research projects, which use existing UNICORE components to implement advanced features, high level services, and support for applications from a growing range of domains. In order to foster these ongoing developments, UNICORE is available as open source under BSD licence at SourceForge, where new releases are published on a regular basis. This paper is a review of the UNICORE achievements so far and gives a glimpse on the UNICORE roadmap.
a certain critical separation they would spiral-in and merge induced by gravitational radiation. The computer programmes EUROSTAR and NBODY6++ developped for use with mpi libraries maintain high accuracy over billions of integration timesteps, allowing a detailed analysis of the orbit of the black hole(s), its interactions with field stars, and the two-body relaxation in the surrounding dense stellar system. 1 Binary Black Holes in Galactic Nuclei Massive black holes are very likely to reside in the centres of galaxies as a fossile of earlier acticity 16, 18 . For their formation collisionless dynamical general relativistic collapse or dissipative processes during galaxy formation have been proposed 32 , but a complete and quantitative understanding does not yet exist (compare, however, some related work in that direction in 17, 4 ). Nowadays there is strong evidence that the formation of central black holes in galaxies can at least qualitatively be understood in semi-anal
Interactive Access in the UNICORE Environment
- S Anderlik
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- J Barton
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- H Nielson