Glossary

AAA

Short for Authentication, Authorization and Accounting, a system to control what resources users have access to and to keep track of what activity they perform on them.

Accounting

The process of keeping track of a user's activity while accessing the resources, including the amount of time spent in their usage, the services accessed while there and the amount of data transferred during the session. Accounting data are used for trend analysis, capacity planning, billing, auditing, and cost allocation.

Authentication

The process of identifying a user usually based on username and password. Authentication is based on the idea that each individual user has a unique piece of information that sets him or her apart from other users.

Authorization

The process of granting or denying a user access to resources once the user has been authenticated through the appropriate authentication mechanism, e.g. username and password. The amount of information and the amount of services the user has access to depend on the user's authorization level.

Certification Authority

A trusted third-party organization or company that issues digital certificates used to create digital signatures and public-private key pairs. The role of the CA in this process is to guarantee that the individual granted the unique certificate is, in fact, who he or she claims to be.

Collection

A set of Information Object, which is in turn an Information Object, The extension of a collection consists of the Information Objects it contains. A collection may be defined by a membership criterion, which is the intension of the collection.

Component

A constituent of a larger whole. In the gCube context is a reusable block of software (code, metadata and other resources, depending on the technology) consisting of one or more sub-elements, often strongly interrelated, that encloses a specific (usually small) domain of functionality. Components can be consumed / distributed in libraries or executables (standalone or services) and offer technology dependent interfaces for their consumption.

eInfrastructure

The term e-Infrastructure refers to the new research environment in which all researchers - whether working in the context of their home institutions or in national or multinational scientific initiatives - have shared access to unique or distributed scientific facilities (including data, instruments, computing and communications), regardless of their type and location in the world. (CORDIS, [1])

Framework

A set of software (compile/run-time elements, libraries, tools, services), documentation, policies, procedures, that supports the implementation of technology specific higher-level software elements.

gCore Framework (gCF)

A java-based application framework for (i) building high-quality gCube services that are easily deployable both via the infrastructure facilities and to a human and (ii) providing a runtime environment for such services. The framework is distributed with gCore.

gCube

gCube stands for Grid for Hardware, Data and Software. It is a multifaceted system as reflected by the definition below.

A distributed service-based system for the autonomic operation of an e-Infrastructure for Virtual Research Environments.

A distributed runtime platform for the development of interactive, service based e-Science applications.

A full-featured, expandible, professional-grade and service-based platform that is sufficiently functional to create a broad range of dynamic production-ready applications (VREs).

gCube Core Distribution (gCore)

A packaging of the components of the gCube system which are ubiquitously deployed on each gHN of a gCube infrastructure.

gCube Hosting Node (gHN)

The topological unit of a gCube infrastructure. An abstraction over a container running on a given port and hosting at least a minimal set of basic gCube services (the local services) dedicated to the host management.

gLite

gLite (pronounced "gee-lite") is a middleware for Grid computing. Born as a part of the EGEE Project, gLite provides a bleeding-edge, best-of-breed framework for building Grid applications tapping into the power of distributed computing and storage resources across the Internet.

Information Object

A logical unit of information potentially consisting of and linked to other Information Objects as to form compound objects.

Information Retrieval

Information retrieval (IR) is the act/science of searching for documents, for information within documents and for metadata about documents, as well as that of searching relational databases and the World Wide Web. (Wikipedia, August 2008, [2])

Library (Software Library)

A reusable set of (locally) executable/embedable software (code, metadata and other resources, depending on the technology) that encloses one or more components and (usually) is not standalone usable. Libraries are packaged as indentifiable "file system" elements, offer technology dependent interfaces for their consumption and are consumed locally.

Resource Provider (Resource Owner)

The entity who owns a resource and thus has full privileges in using it.

Search Engine

A search engine encompasses all the tools and functionalities for enabling and perfoming lookups for information in pools of data / information. As such it might contain functional (for supporting various types of searches, processing/transforming the data, performing natural language processing etc) and non-functional (for enhancing performance, security, availability and reliability) elements of a large range of funtionalities: indexing, feature extraction, optimizer, feature-distance calculator, XML processing/filtering, visualisation etc. Harvesting / updating and storage handling is considered a boundary operation for the Search Engine in D4Science. A search engine is not mandatorily bound to web searching, and can often, in simple scenarios, be implemented over a single index (such as a FullText one).

Service

A standalone executable piece of software that offer its functionality to other executable software. Services do not involve human intervention for their execution and often adopt a technology independent communication protocol. Services can be locally ore remotelly consumed and usually support network discovery and consumption.

Service Oriented Architecture (SOA)

The approach of composing large systems out of looselly coupled services, which expose well defined interfaces for their invocation. Service Oriented Architecture is orthogonal to Component Oriented development and Object Oriented Programming.

Standalone Executables

Software, build on a technology-specific framework, that can consumes libraries, services and other resources that can ultimatelly execute and offer functionality on its own. Standalone executables can act as desktop/user applications or services themselves

Subsystem

A part of a system that can be considered a system by its own.

System

A set of connected things or parts forming a complex whole.

Virtual Organisation

A virtual organisation (VO) is a dynamic pool of distributed resources shared by a dynamic set of users belonging to one or more organizations in a trusted way.

Virtual Research Environment (VRE)

An integrated and coordinated working environment providing participants with the resources (data, instruments, processing power, communication tools, etc.) they need to accomplish the envisaged task. The resources shared can be of very different nature and vary across application and institutional domains. Usually they include content resources, application services that manipulate these content resources to produce new knowledge, and computational resources, which physically store the content and support the processing of the services.

From a system point of view, a VRE is a pool of gCubeResources dynamically aggregated to behave as a unit w.r.t. the application context the VRE is expected to serve. Each VRE is a view over the potentially unlimited pool of resources made available through the Infrastructure that (i) is regulated by the user community needs and the resources sharing policies and (ii) produces a new VO constraining the scope and usage of resources actors playing in the VRE are subject to.

Web Service

A software system designed to support interoperable machine-to-machine interaction over a network. It has an interface described in a machine-processable format (specifically WSDL). Other systems interact with the Web service in a manner prescribed by its description using SOAP-messages, typically conveyed using HTTP with an XML serialization in conjunction with other Web-related standards.