[Show abstract][Hide abstract] ABSTRACT: The motivation of this work fits with the general vision to enable e-health for European citizens, irrespective of their social and financial status and their place of residence. Services to be provided include access to a high-quality early diagnostic and prognostic service for the Alzheimer Disease and other forms of dementia, based both on the European Research and Education Networks and the European Grid Infrastructure. The present paper reports on the architecture and services of a Science Gateway developed in the context of the DECIDE project, which aims to support the medical community in its daily duties of patients’ examination and diagnosis. The implementation of the Science Gateway is described with particular focus on the standard technologies adopted to ease the access by non IT-.expert users. The work leverages on an authentication and authorization infrastructure based on Identity Federations and robot certificates and on the adoption of the SAGA standard for middleware-independent Grid interaction. The architecture and the functionalities of the digital repository for medical image storage and analysis are also presented.
Journal of Grid Computing 12/2012; 10(4):689-707. · 1.60 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In this paper we present the architecture of a framework for building Science Gateways supporting official standards both for user authentication and authorization and for middleware-independent job and data management. Two use cases of the customization of the Science Gateway framework for Semantic-Web-based life science applications are also described.
Studies in health technology and informatics 01/2012; 175:119-30.
[Show abstract][Hide abstract] ABSTRACT: Science Gateways are playing an important role in scientific research performed using e-Infrastructures and their relevance will further increase with the development of more sophisticated user interfaces and easier access mechanism. Through the highly collaborative environment of a Science Gateway, users spread around the world and belonging to various Virtual Research Communities can easily cooperate to reach common goals and exploit all the resources of the cyber-infrastructure they are entitled to use. One of the major tasks of a Science Gateway is to supervise the user access to the available services, denying the use to those people who are not authorised. This activity has to comply with the role of users inside the VRC. Users operating in a Science Gateway can belong to different organisations having their own security policies and the Virtual Research Community has to comply with them. As a result, the security chain inside the Science Gateway has to allow each organisation to keep the control of their users hiding, at the same time, the complexity of the security mechanisms underneath the portal. In this work we present a general framework to build Science Gateways  and the customisations made to meet the requirements of a couple of use cases coming from different scientific communities: those of the European Union funded DECIDE (www.eu-decide.eu) and INDICATE (www.indicate-project.eu) projects. The goal of DECIDE project is to design, implement, and validate a Science Gateway for the computer-aided extraction of diagnostic markers from medical images for the early diagnosis of Alzheimer Disease and other forms of dementia. Using the same platform neurologists, physicians and scientists can store their images and data on grid and perform analysis and comparisons with a huge set of reference cases available on grid. The INDICATE project aims instead at demonstrating, with real-life examples, the advantages of the adoption of e-Infrastructures in the digital cultural heritage domain. The plugin developed enables INDICATE Science Gateway, and its digital cultural heritage community, to access two different e-Infrastructure repositories in an easy way with a friendly user interface but keeping the digital resources safe and the transactions private. The framework defined to support the above use cases is an extension of Liferay portal framework, which provides a whole set of web 2.0 tools and services for the development of generic portals. These have been integrated with a more flexible security workflow and a new set of portlets to access the Grid services. The final architecture of a Science Gateway consists of two part: a front-end building the graphical user interface, and a back-end providing the access to the grid services implemented. A major extension to Liferay is the security system. The new developed security system merges three different security mechanisms in a single workflow allowing users to access Grid resources based on the credentials provided by the organisations they belong to. The idea behind was to combine Shibboleth2 identities in the front-end with X.509 proxies generated by robot certificates in the back-end. The former enables the federation of organisations having different authentication policies while the latter allows users to access Grid resources, without needing any personal certificates whose request and management procedure is very often judged quite cumbersome by non-experts. The "glue" between the two layers is an LDAP server running in the back-end that implements a mechanism to map authorised users on Grid resources. Services managing user and grid credentials are not integrated in Liferay Portal but run in different hosts, in order to increase the reliability and security of the Science Gateway. Once the user is authenticated, the portlets developed provide the functionalities to manage the Grid credentials in order to access the e-Infrastructure behind. The portlet-based interface to Grid is built on the OGF-standard SAGA Java API and it is not bound to any particular middleware. Besides the interaction with the computational services of an e-Infrastructure, the proposed framework includes the possibility to easily build and manage data repositories interacting with the gLibrary framework  and to encrypt/decrypt sensible data with the Secure Storage System .
[Show abstract][Hide abstract] ABSTRACT: In the last 10 years, a new way of doing science is spreading in the world thank to the development of virtual research communities
across many geographic and administrative boundaries. A virtual research community is a widely dispersed group of researchers
and associated scientific instruments working together in a common virtual environment. This new kind of scientific environment,
usually addressed as a “collaboratory”, is based on the availability of high-speed networks and broadband access, advanced
virtual tools and Grid-middleware technologies which, altogether, are the elements of the e-Infrastructures. The European
Commission has heavily invested in promoting this new way of collaboration among scientists funding several international
projects with the aim of creating e-Infrastructures to enable the European Research Area and connect the European researchers
with their colleagues based in Africa, Asia and Latin America. In this paper we describe the actual status of these e-Infrastructures
and present a complete picture of the virtual research communities currently using them. Information on the scientific domains
and on the applications supported are provided together with their geographic distribution.
Journal of Grid Computing 06/2011; 9:155-184. · 1.60 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A measure to estimate the value that Grids can provide to potential users can be obtained by assessing the resources availability, middleware overhead and infrastructure reliability incurred when running an application in a transcontinental e-Infrastructure like EGEE. Celebrating the recent MoU between EELA-2  and EUAsiaGrid  projects, both co-funded by EC under the Seventh Framework Programme, this paper aims at providing a comparative study between their respective Grid infrastructures. Current monitoring tools provide information on the resources status. These figures are useful for Grid managers in order to check the availability of the services but not for end users because they do not provide any indication on the execution of users' applications, such as the average job delay. In our approach, we randomly submitted 10 jobs per day during 1 week both project's infrastructures and measured its total execution time. No special requirements were set on the JDL files and we did not carry about the level of availability of the computing resources (CEs) neither about the number of jobs concurrently running at a giving moment. We let the core Workload Management System (WMS) of each project to automatically choose which CE to submit the jobs, considering both EUAsiaGrid and EELA-2 infrastructures as single entities. The analysis of the results can be used to measure the quality of services provided by both projects to its respective user communities.
[Show abstract][Hide abstract] ABSTRACT: The COMETA e-Infrastructure running in Sicily is compliant with the EGEE middleware and specifications offering a great computing power and huge storage capacity. Since its beginning one of the main goals has been to extend the adoption of Grid paradigm from the academic to business world. Several software and hardware extensions have been implemented in order to enhance the infrastructure performances; they include a new low-latency net layer reserved to heavy parallel applications; some modifications to the parallel job submission and execution procedures for a better support of MPI-based applications; new tools for job monitoring and file catalogue interaction; a scheduling policy tailored on the requirements of a complex environment hosting heterogeneous jobs; the GridLM license server able to grant access to commercial software only to authorised users; finally, the Secure Storage Service defends from insider abuse and completes a very high security level environment. The proposed business model includes a wide range of services collectively defined as Infrastructure-as-a-Service. All the above components result in a powerful and flexible platform, easy to use for any applications and open to further developments.
ICE-B 2010 - Proceedings of the International Conference on e-Business, Athens, Greece, July 26 - 28, 2010, ICE-B is part of ICETE - The International Joint Conference on e-Business and Telecommunications; 01/2010
[Show abstract][Hide abstract] ABSTRACT: The increasing digital divide makes scientists, educators, and students from many parts of the worlds not able to take advantage
of last ICT developments. Therefore, many countries are increasingly marginalised as the world of education and science becomes
increasingly Internetdependent. The Grid INFN Laboratory for Dissemination Activities (GILDA) provides a Grid training infrastructure
used to spreads the Grid technology to a wider range of users. So far several scientific communities such as biologists, physicists
and many others have been successfully supported. Currently, GILDA is the choice infrastructure for the EUAsiaGrid project
training activity which aims at creating new Grid communities in Asia. The training on GILDA allows new users to experienced
this new technology and understand their requirements before to perform expensive investments. In this contribution we will
report on the latest status of GILDA services and on the training activities recently carried out in the supported projects.
[Show abstract][Hide abstract] ABSTRACT: In the first article of this series, we identified the need for teaching environments that provide infrastructure to support education and training in distributed computing. Training infrastructure, or t-infrastructure, is analogous to the teaching laboratory in biology and is a vital tool for educators and students. In practice, t- infrastructure includes the computing equipment, digital communications, software, data, and support staff necessary to teach a course. The International Summer Schools in Grid Computing (ISSGC) series and the first International Winter School on Grid Computing (IWSGC 08) used the Grid INFN Laboratory of Dissemination Activities (GILDA) infrastructure so students could gain hands-on experience with middleware. Here, we describe GILDA, related summer and winter school experiences, multimiddleware integration, t-infrastructure, and academic courses, concluding with an analysis and recommendations.
[Show abstract][Hide abstract] ABSTRACT: Since the birth of computational and data grids, many middlewares have been developed and deployed. Currently, they are used in a multitude of isolated e-infrastructures and a hot topic in grid technology in the last year or so has been that of middleware interoperability/interoperation. In this paper we present a new approach to grid interoperation based on the so called middleware co-existence. Following this approach, different middlewares are deployed on the same infrastructure and allow the same users to access and/or share the resources, with well defined policy, regardless the middleware they want to use. Although this approach has been used for educational purposes in a training infrastructure, it is so general that it could be used everywhere the interoperation is a concern for the users and/or site managers of an e-infrastructure.
e-Science and Grid Computing, IEEE International Conference on; 01/2008
[Show abstract][Hide abstract] ABSTRACT: Huge amount of data can be stored on Grid Storage Elements, but few tools are provided by the EGEE gLite middleware to easily search and retrieve files a user is looking for. File catalogues can help organizing data in hierarchical structures, but they do not provide a way to describe file contents. On the other hand, we have Metadata Services, that can be used to attach additional information to files, but this services are not so easy to use by non-experienced people. In this paper a easy-to-use system to handle digital assets stored as grid file is presented. Such system is called gLibrary. It offers a intuitive interface that allow users to browse and filter the available entries, as well as to retrieve or upload a file by copying it from one of the Storage Elements (SEs) into user's local machine, or vice-versa.
Enabling Technologies: Infrastructure for Collaborative Enterprises, 2007. WETICE 2007. 16th IEEE International Workshops on; 07/2007
[Show abstract][Hide abstract] ABSTRACT: Grid computing empowers users to employ a huge amount of resources to perform their task. Many services allows to access these resources with different methods and supporting different QoS. In order to use the services an agreement between the user and the provider has to be defined, where users specify the QoS required from the service to perform their activities correctly and, at the same time, providers declare the QoS offered with the service. Current solutions to reach an agreement between users and providers do not consider many aspects related to the use or misuse of services that can seriously influence or even nullify the agreement itself. This paper presents a simple formalism to define more rigourously an agreement, and a discussion about several problems related to the introduction of agreements. Actually, at the time when an agreement is signed many information are unknown from users and providers, therefore they take a risk to sign an agreement which can sometimes be wrong. Moreover, if problems arise during the execution, users and providers cannot decide who is responsible for the problem and eventually refund the other.
Enabling Technologies: Infrastructure for Collaborative Enterprises, 2007. WETICE 2007. 16th IEEE International Workshops on; 07/2007
[Show abstract][Hide abstract] ABSTRACT: Existing resource brokers for computational Grids only focus on locating a machine (computational resource) within a cluster that has the least load. Such simple brokers are ineffective in commercial and complex environments where negotiation over price, time and service-level agreements are required to establish a contract before users are authorised to use a computational resource. This paper presents a brokering system, utilising the Job Submission Description Language (JSDL) standard and extends the Unicore/GS Resource Broker, that extends brokering with scheduling (resource availability) and simple pricing policy management. The brokering system improves the effectiveness in negotiating contracts for the use of computational resources on the Grid. The architecture and implementation have developed a plug-in for Unicore/GS Resource broker and integrates an externally hosted calendaring service to support the described functionality, and demonstrates the feasibility of building systems by composing autonomous services hosted on the network.
Second International Conference on e-Science and Grid Technologies (e-Science 2006), 4-6 December 2006, Amsterdam, The Netherlands; 01/2006
[Show abstract][Hide abstract] ABSTRACT: This paper discusses an approach to evaluating the separa-tion of concerns for an object-oriented software system. For assessing this separation, the developer is asked to specify the nature of classes through annotations. Automatic identi-fication of some structural characteristics (e.g., inheritance, libraries, synchronisation) is used to appraise the composi-tion and intertwining of concerns inside a class.
Proceedings of the 2005 ACM Symposium on Applied Computing (SAC), Santa Fe, New Mexico, USA, March 13-17, 2005; 01/2005
[Show abstract][Hide abstract] ABSTRACT: The grid is a dynamic environment in which resources can quickly go from idle to busy state depending on application operations. In such a scenario, resources can be used more effectively by introducing reservation and allocation. As a solution, this paper proposes STREGA: a software architecture that handles resource reservation and greatly simplifies the integration of applications with a grid environment. In it, resources needed by applications are automatically detected, and operations such as resource reservation and allocation are accordingly transparently performed, e.g. using Globus services. Within STREGA, some components are aimed at understanding the needs of application classes, other components dynamically re-adapt resource requests on the basis of the observed application behaviour. Additional components are proposed to support reservation when this is unavailable from the underlying system (i.e. Globus and the OS).
Enabling Technologies: Infrastructure for Collaborative Enterprises, 2004. WET ICE 2004. 13th IEEE International Workshops on; 07/2004
[Show abstract][Hide abstract] ABSTRACT: Typically, real-time applications are developed by introducing real time concerns into functionality concerns. This leads
to difficulties in the reuse of applications, and to limited capabilities of the underlying runtime system to adapt itself
for the sake of meeting the desired deadline.
In this paper we explore an approach that supports the automated development of real-time aware applications. This is made
possible by a tool that performs a suitable analysis and transformation, aiming to automatically incorporate real-time concerns
into an unaware application.
The analysis serves to identify, within the application, subtasks and (possibly) subsubtasks, together with their minimum
and maximum execution times and partial deadlines. The transformation has the twofold aim of monitoring critical timing aspects
of the execution, and adapting the application on-the-fly to help meeting the deadlines.
Adaptation measures involve not only task scheduling, but also the substitution of application parts, as well as the activation
of additional (possibly distributed) hardware and software resources.
On the Move to Meaningful Internet Systems 2004: OTM 2004 Workshops: OTM Confederated International Workshops and Posters, GADA, JTRES, MIOS, WORM, WOSE, PhDS, and INTEROP 2004, Agia Napa, Cyprus, October 25-29, 2004. Proceedings; 01/2004
[Show abstract][Hide abstract] ABSTRACT: Although Java reduces the time to market of embedded sys- tems, for some contexts developers are still forced to consider, beside application concerns, checks and handling activities for anomalous con- ditions that can occur on hardware devices. Typically, applications and handling of anomalous conditions are unrelated, and developers should be provided with means to treat them separately. Reflective systems have been successfully used to separate different concerns. However, spe- cial care is required when using them in embedded systems, due to the run time overhead that they can cause. In this paper, we propose what we call selective reflective behaviour, which aims at reducing the run time overhead of reflective systems. An efficient implementation of this behaviour is also proposed, which is suitable even for embedded Java sys- tems. The paper also presents an example of a meta level that handles anomalous conditions for the embedded systems in a production cell.
On The Move to Meaningful Internet Systems 2003: OTM 2003 Workshops, OTM Confederated International Workshops, HCI-SWWA, IPW, JTRES, WORM, WMS, and WRSM 2003, Catania, Sicily, Italy, November 3-7, 2003, Proceedings; 01/2003