Global Grids and Software Toolkits: A Study of Four Grid Middleware Technologies

Grid is an infrastructure that involves the integrated and collaborative use of computers, networks, databases and scientific instruments owned and managed by multiple organizations. Grid applications often involve large amounts of data and/or computing resources that require secure resource sharing across organizational boundaries. This makes Grid application management and deployment a complex undertaking. Grid middlewares provide users with seamless computing ability and uniform access to resources in the heterogeneous Grid environment. Several software toolkits and systems have been developed, most of which are results of academic research projects, all over the world. This chapter will focus on four of these middlewares--UNICORE, Globus, Legion and Gridbus. It also presents our implementation of a resource broker for UNICORE as this functionality was not supported in it. A comparison of these systems on the basis of the architecture, implementation model and several other features is included.Comment: 19 pages, 10 figure

Extending and Implementing the Self-adaptive Virtual Processor for Distributed Memory Architectures

Many-core architectures of the future are likely to have distributed memory organizations and need fine grained concurrency management to be used effectively. The Self-adaptive Virtual Processor (SVP) is an abstract concurrent programming model which can provide this, but the model and its current implementations assume a single address space shared memory. We investigate and extend SVP to handle distributed environments, and discuss a prototype SVP implementation which transparently supports execution on heterogeneous distributed memory clusters over TCP/IP connections, while retaining the original SVP programming model

A Taxonomy of Data Grids for Distributed Data Sharing, Management and Processing

Data Grids have been adopted as the platform for scientific communities that need to share, access, transport, process and manage large data collections distributed worldwide. They combine high-end computing technologies with high-performance networking and wide-area storage management techniques. In this paper, we discuss the key concepts behind Data Grids and compare them with other data sharing and distribution paradigms such as content delivery networks, peer-to-peer networks and distributed databases. We then provide comprehensive taxonomies that cover various aspects of architecture, data transportation, data replication and resource allocation and scheduling. Finally, we map the proposed taxonomy to various Data Grid systems not only to validate the taxonomy but also to identify areas for future exploration. Through this taxonomy, we aim to categorise existing systems to better understand their goals and their methodology. This would help evaluate their applicability for solving similar problems. This taxonomy also provides a "gap analysis" of this area through which researchers can potentially identify new issues for investigation. Finally, we hope that the proposed taxonomy and mapping also helps to provide an easy way for new practitioners to understand this complex area of research.Comment: 46 pages, 16 figures, Technical Repor

Their memory:exploring veterans’ voices, virtual reality and collective memory

This paper focuses on the virtual reality (VR) project Their Memory and details the development and evaluation of virtual reality environments and experiences with respect to its impact on young people (14-35 demographic) with the narratives of veterans in Scotland. As part of the AHRC Immersive Experiences program, Their Memory was created to explore how game design techniques and immersive technology could be used to enhance existing historical research and enrich narratives to bring expansive experiences to hard-to-reach audiences. The project worked directly with the veterans’ charity, Poppyscotland, to create an environment and experience that would resonate with new audiences, and explore documentary and storytelling techniques for the commemoration of war and conflict. The design of the project evolved through co-design sessions with veterans and young people and culminated in the creation of a short, thought-provoking, narrative-driven experience. The VR experience enabled players to connect with the memories of veterans in Scotland and exploring the different conflicts or situations they experienced and how they make sense of them. The project brought together cross-sector expertise to research how immersive experiences can help memory-based organizations in engaging with wider audiences, raise awareness, and diversify current learning outputs. The paper details the design and development of the Virtual Reality project, through co-design, and how this engaged the audience and evolved the experience created. The paper includes a summative evaluation of events conducted with schoolchildren to assess the project and concludes with how the project evidences impact upon audiences and the potential for both technology and the experience