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Grid Computing P23
A NEW CHALLENGE FOR APPLICATION DEVELOPERS Scientific and engineering applications have driven the development of high-performance computing (HPC) for several decades. Many new techniques have been developed over the years to study increasingly complex phenomena using larger and more demanding jobs with greater throughput, fidelity, and sophistication than ever before. Such techniques are implemented as hardware, as software, and through algorithms, including now familiar concepts such as vectorization, pipelining, parallel processing, locality exploitation with memory hierarchies, cache use, and coherence....
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Grid Computing P24
The emergence of Grid computing as the prototype of a next-generation cyber infrastructure for science has excited high expectations for its potential as an accelerator of discovery, but it has also raised questions about whether and how the broad population of research professionals, who must be the foundation of such productivity, can be motivated to adopt this new and more complex way of working. The rise of the new era of scientific modeling and simulation has, after all, been precipitous, and many science and engineering professionals have only recently become comfortable with the relatively simple world of uniprocessor workstations and...
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Grid Computing P25
Recent developments in high-speed networking enables collective use of globally distributed computing resources as a huge single problem-solving environment, also known as the Grid. The Grid not only presents a new, more difficult degree of inherent challenges in distributed computing such as heterogeneity, security, and instability, but will also require the constituent software substrates to be seamlessly interoperable across the network
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Grid Computing P26
Over the past few years, various international groups have initiated research in the area of parallel and distributed computing in order to provide scientists with new programming methodologies that are required by state-of-the-art scientific application domains. These methodologies target collaborative, multidisciplinary, interactive, and large-scale applications that access a variety of high-end resources shared with others.
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Grid Computing P27
Computational Grids [1] have emerged as a distributed computing infrastructure for providing pervasive, ubiquitous access to a diverse set of resources ranging from highperformance computers (HPC), tertiary storage systems, large-scale visualization systems, expensive and unique instruments including telescopes and accelerators. One of the primary motivations for building Grids is to enable large-scale scientific research projects to better utilize distributed, heterogeneous resources to solve a particular problem or set of problems....
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Grid Computing P28
In this chapter, we discuss the development, architecture, and functionality of the National Partnership for Advanced Computational Infrastructure NPACI Grid Portals project. The emphasis of this paper is on the NPACI Grid Portal Toolkit (GridPort); we also discuss several Grid portals built using GridPort including the NPACI HotPage. We discuss the lessons learned in developing this toolkit and the portals built from it, and finally we present our current and planned development activities for enhancing GridPort and thereby the capabilities, flexibility, and ease-of-development of portals built using GridPort....
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Grid Computing P29
This chapter describes a GridService demonstrator built around the Unicore Grid environment, its architectural design and implementation [1]. It then examines some lessons learned from the process of developing an implementation of a family of GridServices that conforms to the Open Grid Services Architecture (OGSA) [2] and the Grid Service Specification [3]. The goals of this project were two fold. Primarily, it is only through implementation that complexities such as those that arise in OGSA can be fully understood and analyzed....
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Grid Computing P30
Computational Grid technologies hold the promise of providing global scale distributed computing for scientific applications. The goal of projects such as Globus [1], Legion [2], Condor [3], and others is to provide some portion of the infrastructure needed to support ubiquitous, geographically distributed computing [4, 5]. These metacomputing tools provide such services as high-throughput computing, single login to resources distributed across multiple organizations, and common Application Programming Interfaces (APIs) and protocols for information, job submission, and security services across multiple organizations. ...
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Grid Computing P31
A collaboratory is defined as a place where scientists and researchers work together to solve complex interdisciplinary problems, despite geographic and organizational boundaries [1]. The growth of the Internet and the advent of the computational ‘Grid’ [2, 3] have made it possible to develop and deploy advanced computational collaboratories [4, 5] that provide uniform (collaborative) access to computational resources, services, applications and/or data. These systems expand the resources available to researchers, enable ...
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Grid Computing P32
Most, if not all, Computational Grid resource allocation and scheduling research espouses one of two paradigms: centralized omnipotent resource control [1–4] or localized application control [5–8]. The first is not a scalable solution either in terms of execution efficiency (the resource broker or scheduler becomes a bottleneck) or fault resilience (the allocation mechanism is a single point of failure). On the other hand, the second approach can lead to unstable resource assignments as ‘Grid-aware’ applications adapt to compete for resources....
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Grid Computing P33
Computational Grids [1, 2] are large collections of resources such as computers, networks, on-line instruments, or storage archives, and they are becoming popular platforms for running large-scale, resource-intensive applications. Many challenges exist in providing the necessary mechanisms for accessing, discovering, monitoring, and aggregating Grid resources. Consequently, a tremendous effort has been made to develop middleware technology to establish a Grid software infrastructure (GSI) [2–4]. Although middleware provides the fundamental building blocks, the APIs and access methods are often too complex for end users. Instead, there is a need for abstractions and tools that make it easy for users to deploy...
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Grid Computing P34
Built upon a foundation of Simple Object Access Protocol (SOAP), Web Services Description Language (WSDL) and Universal Description Discovery and Integration (UDDI) technologies, Web services have become a widely accepted industry standard in the last few years [1, 2]. Because of their platform independence, universal compatibility, and network accessibility, Web services will be at the heart of the next generation of distributed systems. As more vendors offer SOAP tools and services, the advantages of using SOAP and Web services as an integration point will become even more pronounced. The Grid computing community has also recognized the importance of using Web...
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Grid Computing P35
This book, Grid Computing: Making the Global Infrastructure a Reality, is divided into four parts. This short chapter introduces the last part, Part D, on applications for the Grid. All the chapters in the book contain material relevant for Grid applications, but in this part the focus is the applications themselves. Some of the previous chapters also cover applications as part of an overview or to illustrate a technological issue.
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Grid Computing P36
There are many issues that should be considered in examining the implications of the imminent flood of data that will be generated both by the present and by the next generation of global ‘e-Science’ experiments. The term e-Science is used to represent the increasingly global collaborations – of people and of shared resources – that will be needed to solve the new problems of science and engineering [1]. These e-Science problems range from the simulation of whole engineering or biological systems, to research in bioinformatics, proteomics and pharmacogenetics. In all these instances we will need to be able to pool...
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Grid Computing P37
From the standpoint of the average user, today’s computer networks are extremely primitive compared to other networks. While the national power, transportation, and telecommunications networks have evolved to their present state of sophistication and ease of use, computer networks are at an early stage in their evolutionary process. Eventually, users will be unaware that they are using any computer but the one on their desk, because it will have the capability to reach out across the national network and obtain whatever computational resources that are necessary...
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Grid Computing P38
THE VIRTUAL OBSERVATORY Astronomers have always been early adopters of technology, and information technology has been no exception. There is a vast amount of astronomical data available on the Internet, ranging from spectacular processed images of planets to huge amounts of raw, processed and private data. Much of the data is well documented with citations, instrumental settings, and the type of processing that has been applied. In general, astronomical data has few copyright, or privacy or other intellectual property restrictions in comparison with other fields of science, although fresh data is generally sequestered for a year or so while the observers...
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Grid Computing P39
INTRODUCTION: SCIENTIFIC EXPLORATION AT THE HIGH-ENERGY FRONTIER The major high-energy physics (HEP) experiments of the next twenty years will break new ground in our understanding of the fundamental interactions, structures and symmetries that govern the nature of matter and space-time. Among the principal goals are to find the mechanism responsible for mass in the universe, and the ‘Higgs’ particles associated with mass generation, as well as the fundamental mechanism that led to the predominance of matter over antimatter in the observable cosmos. The largest collaborations today, such as CMS [1] and ATLAS [2] who are building experiments for CERN’s Large...
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Grid Computing P40
Computational biology is undergoing a revolution from a traditionally compute-intensive science conducted by individuals and small research groups to a high-throughput, datadriven science conducted by teams working in both academia and industry. It is this new biology as a data-driven science in the era of Grid Computing that is the subject of this chapter. This chapter is written from the perspective of bioinformatics specialists who seek to fully capitalize on the promise of the Grid and who are working with computer scientists and technologists developing biological applications for the Grid. To understand what has been developed and what is proposed...
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Grid Computing P41
This chapter introduces a project named eDiamond, which aims to develop a Grid-enabled federated database of annotated mammograms, built at a number of sites (initially in the United Kingdom), and which ensures database consistency and reliable image processing. A key feature of eDiamond is that images are ‘standardised’ prior to storage. Section 41.3 describes what this means, and why it is a fundamental requirement for numerous grid applications, particularly in medical image analysis, and especially in mammography....
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Grid Computing P42
In line with the usual chemistry seminar speaker who cannot resist changing the advertised title of a talk as the first, action of the talk, we will first, if not actually extend the title, indicate the vast scope of combinatorial chemistry. ‘Combinatorial Chemistry’ includes not only the synthesis of new molecules and materials, but also the associated purification, formulation, ‘parallel experiments’ and ‘high-throughput screening’ covering all areas of chemical discovery.
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Grid Computing P43
In this short article, we aim to describe the relevance of Grids in education. As in fact information technology for education builds on that for any organization, we first discuss the implication of Grids and Web services for any organization – we call this an Enterprise to stress the importance of the Enterprise Grids and the different roles of general and specific features in any Grid deployment. The discussion of the importance of Grids for virtual organizations in Chapter 6 already implies its importance in education where our organization involves learners, teachers and other stakeholders such as parents and employers....
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GSM and UMTS (P1)
1 Introduction to the Content of the Book This book describes how global mobile communication was made. It is written for those who want or need to know how this was achieved e.g.: † Young professionals who want to build their career on GSM and UMTS and need to understand the basics † Strategic and technical planners who want to drive the future GSM and UMTS development † Strategists who plan to repeat GSM’s success in the fourth generation † Academics, who want to understand and analyse the development of GSM and UMTS; † Activists in other large scale international communication projects...
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GSM and UMTS (P2)
The Situation in the Early 1980s: A Spectrum Allocation Opens the Possibility to Overcome the European Patchwork of Incompatible Systems At the World Administrative Radio Conference in 1979 (WARC ’79), a decision was taken to set aside a block of radio spectrum in the 900 MHz range for use in land mobile communication systems in Zone 1, which in the terminology of the Radio Regulations means Europe. Beyond this, little was said about how the spectrum should be used, such as the allocation to public systems versus private ones....
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GSM and UMTS (P3)
The Detailed Specification Work Leading to the GSM Phase 1 Standard used for the Opening of Service (1987–1991) Thomas Haug 1 Mid-1987 was a milestone in the work of GSM. I think everybody in the group felt, despite what they might have felt earlier, that the agreement on the basic parameters in the air interface marked the turning point in the work. Another very important event took place in 1987 after years of preparations, i.e. the Memorandum of Understanding (MoU), signed by – initially – 14 operators who made a firm commitment to implement the system by 1991....
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GSM and UMTS (P4)
: Consolidating GSM Phase 1 and Evolving the Services and Features to GSM Phase 2 in ETSI SMG (1992–1995) Philippe Dupuis 1 4.1 General When the agreement on the selection of the GSM technology had been achieved some people thought that the rest would be easy. We knew however that producing a set of specifications that would ensure the interpretability of mobile stations produced by any mobile terminal manufacturer, and network infrastructure produced by any manufacturer of network infrastructure, or the interoperability of different elements of the network infrastructure produced by different manufacturers, would be a formidable task, particularly in the relatively short...
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GSM and UMTS (P5)
The Invention of the Phase 21 Concept In 1992 SMG had to stop adding new items to the phase 2 work programme. It was nevertheless clear that there would be something after phase 2. Some proposed to call it ‘‘phase 3’’. This would of course have later caused some confusion with third generation. But the actual reason why SMG rejected this expression is that it would have suggested a phase 2/phase 3 transition similar to the phase 1/phase 2 transition, while it was thought that, for this further evolution, one should aim at a full cross phase compatibility....
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GSM and UMTS (P6)
US Regulatory Status in the 1990s During the first part of the 1990s, the regulatory climate in the US cellular environment was fashioned by the components of the time. The migration from analogue to digital was underway. The TDMA/FDMA debate had finished and a decision had been made (with TDMA winning) and the TDMA/CDMA public relations wars were in full swing. CDMA was thought by some to be the saviour of the world, capacity wise, and others were firmly committed to TDMA and some even to enhancements of TDMA. A new US President took office in 1993 and one of...
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GSM and UMTS (P7)
Compared to today’s reality, the mobile and wireless communications evolution perspective of the world, at the start of 1985, looks retrospectively rather conservative. While the promise of an accelerated development of mobile communications was sensed as a likely possibility, due notably to the anticipated success of GSM, the most optimistic scenarios for market deployment called for a few million subscribers at the turn of the century.
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GSM and UMTS (P8)
Some experts started working on, or maybe we should say dreaming about, third generation mobile communications in the mid-1980s, even before second generation mobile communications took shape in GSM. UMTS was invented then. It was initially just a vague concept, something which had to one day take over from GSM and therefore had to be superior to GSM. There was also a view that the capacity of GSM would be exhausted just after a few years and that UMTS should thus follow very quickly. This was not a workable proposal as the industry could not throw away GSM developments and...
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GSM and UMTS (P9)
Having read the title, it should not surprise you that this section deals with the creation of the Partnership Project for the standardisation of a Third Generation Mobile Communications System (3GPP). Why, you may ask, in a history book about the GSM and UMTS development, do I want to talk about the establishment of a partnership project? Isn’t it the most natural thing to do? This is, of course, a stance an insider can take today – after nearly 30 months of 3GPP’s creation and the smooth and successful running of this project. As this section will eventually show, it...
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