"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, the authors define this new field. First, they review the "Grid problem," which is defined as flexible, secure, coordinated resource sharing among dynamic collections of individuals, institutions, and resources--what is referred to as virtual organizations. In such settings, unique authentication, authorization, resource access, resource discovery, and other challenges are encountered. It is this class of problem that is addressed by Grid technologies. Next, the authors 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. The authors describe requirements that they believe any such mechanisms must satisfy and discuss the importance of defining a compact set of intergrid protocols to enable interoperability among different Grid systems. Finally, the authors discuss how Grid technologies relate to other contemporary technologies, including enterprise integration, application service provider, storage service provider, and peer-to-peer computing. They maintain that Grid concepts and technologies complement and have much to contribute to these other approaches.

The Anatomy of the Grid: Enabling Scalable Virtual Organizations

"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 Anatomy of the Grid - Enabling Scalable Virtual Organizations

The Globus Toolkit (GT) has been developed since the late 1990s to support the development of service-oriented distributed computing applications and infrastructures. Core GT components address, within a common framework, basic issues relating to security, resource access, resource management, data movement, resource discovery, and so forth. These components enable a broader “Globus ecosystem” of tools and components that build on, or interoperate with, core GT functionality to provide a wide range of useful application-level functions. These tools have in turn been used to develop a wide range of both “Grid” infrastructures and distributed applications. I summarize here the principal characteristics of the latest release, the Web services-based GT4, which provides significant improvements over previous releases in terms of robustness, performance, usability, documentation, standards compliance, and functionality.

https://cs.uwaterloo.ca/~brecht/courses/702/Possible-Readings/grid-computing/globus-v4-icnpc-2005.pdf

Globus toolkit version 4: software for service-oriented systems

In recent years, there has been a dramatic increase in the amount of available computing and storage resources, yet few have been able to exploit these resources in an aggregated form. We present the Condor-G system, which leverages software from Globus and Condor to allow users to harness multi-domain resources as if they all belong to one personal domain. We describe the structure of Condor-G and how it handles job management, resource selection, security and fault tolerance.

Condor-G: a computation management agent for multi-institutional grids

In recent years, there has been a dramatic increase in the number of available computing and storage resources. Yet few tools exist that allow these resources to be exploited effectively in an aggregated form. We present the Condor-G system, which leverages software from Globus and Condor to enable users to harness multi-domain resources as if they all belong to one personal domain. We describe the structure of Condor-G and how it handles job management, resource selection, security, and fault tolerance. We also present results from application experiments with the Condor-G system. We assert that Condor-G can serve as a general-purpose interface to Grid resources, for use by both end users and higher-level program development tools.

Condor-G: A Computation Management Agent for Multi-Institutional Grids

Grid portals, based on standard Web technologies, are increasingly used to provide user interfaces for computational and data grids. However, such Grid portals do not integrate cleanly with existing Grid security systems such as the Grid Security Infrastructure (GSI), due to lack of delegation capabilities in Web security mechanisms. We solve this problem using an online credentials repository system, called MyProxy. MyProxy allows Grid portals to use the GSI to interact with Grid resources in a standard, secure manner. We examine the requirements of Grid portals, give an overview of the GSI, and demonstrate how MyProxy enables them to function together. The architecture and security of the MyProxy system are described in detail.

J. Novotny

Papers

An online credential repository for the Grid: MyProxy