- •Cloud Computing
- •Foreword
- •Preface
- •Introduction
- •Expected Audience
- •Book Overview
- •Part 1: Cloud Base
- •Part 2: Cloud Seeding
- •Part 3: Cloud Breaks
- •Part 4: Cloud Feedback
- •Contents
- •1.1 Introduction
- •1.1.1 Cloud Services and Enabling Technologies
- •1.2 Virtualization Technology
- •1.2.1 Virtual Machines
- •1.2.2 Virtualization Platforms
- •1.2.3 Virtual Infrastructure Management
- •1.2.4 Cloud Infrastructure Manager
- •1.3 The MapReduce System
- •1.3.1 Hadoop MapReduce Overview
- •1.4 Web Services
- •1.4.1 RPC (Remote Procedure Call)
- •1.4.2 SOA (Service-Oriented Architecture)
- •1.4.3 REST (Representative State Transfer)
- •1.4.4 Mashup
- •1.4.5 Web Services in Practice
- •1.5 Conclusions
- •References
- •2.1 Introduction
- •2.2 Background and Related Work
- •2.3 Taxonomy of Cloud Computing
- •2.3.1 Cloud Architecture
- •2.3.1.1 Services and Modes of Cloud Computing
- •Software-as-a-Service (SaaS)
- •Platform-as-a-Service (PaaS)
- •Hardware-as-a-Service (HaaS)
- •Infrastructure-as-a-Service (IaaS)
- •2.3.2 Virtualization Management
- •2.3.3 Core Services
- •2.3.3.1 Discovery and Replication
- •2.3.3.2 Load Balancing
- •2.3.3.3 Resource Management
- •2.3.4 Data Governance
- •2.3.4.1 Interoperability
- •2.3.4.2 Data Migration
- •2.3.5 Management Services
- •2.3.5.1 Deployment and Configuration
- •2.3.5.2 Monitoring and Reporting
- •2.3.5.3 Service-Level Agreements (SLAs) Management
- •2.3.5.4 Metering and Billing
- •2.3.5.5 Provisioning
- •2.3.6 Security
- •2.3.6.1 Encryption/Decryption
- •2.3.6.2 Privacy and Federated Identity
- •2.3.6.3 Authorization and Authentication
- •2.3.7 Fault Tolerance
- •2.4 Classification and Comparison between Cloud Computing Ecosystems
- •2.5 Findings
- •2.5.2 Cloud Computing PaaS and SaaS Provider
- •2.5.3 Open Source Based Cloud Computing Services
- •2.6 Comments on Issues and Opportunities
- •2.7 Conclusions
- •References
- •3.1 Introduction
- •3.2 Scientific Workflows and e-Science
- •3.2.1 Scientific Workflows
- •3.2.2 Scientific Workflow Management Systems
- •3.2.3 Important Aspects of In Silico Experiments
- •3.3 A Taxonomy for Cloud Computing
- •3.3.1 Business Model
- •3.3.2 Privacy
- •3.3.3 Pricing
- •3.3.4 Architecture
- •3.3.5 Technology Infrastructure
- •3.3.6 Access
- •3.3.7 Standards
- •3.3.8 Orientation
- •3.5 Taxonomies for Cloud Computing
- •3.6 Conclusions and Final Remarks
- •References
- •4.1 Introduction
- •4.2 Cloud and Grid: A Comparison
- •4.2.1 A Retrospective View
- •4.2.2 Comparison from the Viewpoint of System
- •4.2.3 Comparison from the Viewpoint of Users
- •4.2.4 A Summary
- •4.3 Examining Cloud Computing from the CSCW Perspective
- •4.3.1 CSCW Findings
- •4.3.2 The Anatomy of Cloud Computing
- •4.3.2.1 Security and Privacy
- •4.3.2.2 Data and/or Vendor Lock-In
- •4.3.2.3 Service Availability/Reliability
- •4.4 Conclusions
- •References
- •5.1 Overview – Cloud Standards – What and Why?
- •5.2 Deep Dive: Interoperability Standards
- •5.2.1 Purpose, Expectations and Challenges
- •5.2.2 Initiatives – Focus, Sponsors and Status
- •5.2.3 Market Adoption
- •5.2.4 Gaps/Areas of Improvement
- •5.3 Deep Dive: Security Standards
- •5.3.1 Purpose, Expectations and Challenges
- •5.3.2 Initiatives – Focus, Sponsors and Status
- •5.3.3 Market Adoption
- •5.3.4 Gaps/Areas of Improvement
- •5.4 Deep Dive: Portability Standards
- •5.4.1 Purpose, Expectations and Challenges
- •5.4.2 Initiatives – Focus, Sponsors and Status
- •5.4.3 Market Adoption
- •5.4.4 Gaps/Areas of Improvement
- •5.5.1 Purpose, Expectations and Challenges
- •5.5.2 Initiatives – Focus, Sponsors and Status
- •5.5.3 Market Adoption
- •5.5.4 Gaps/Areas of Improvement
- •5.6 Deep Dive: Other Key Standards
- •5.6.1 Initiatives – Focus, Sponsors and Status
- •5.7 Closing Notes
- •References
- •6.1 Introduction and Motivation
- •6.2 Cloud@Home Overview
- •6.2.1 Issues, Challenges, and Open Problems
- •6.2.2 Basic Architecture
- •6.2.2.1 Software Environment
- •6.2.2.2 Software Infrastructure
- •6.2.2.3 Software Kernel
- •6.2.2.4 Firmware/Hardware
- •6.2.3 Application Scenarios
- •6.3 Cloud@Home Core Structure
- •6.3.1 Management Subsystem
- •6.3.2 Resource Subsystem
- •6.4 Conclusions
- •References
- •7.1 Introduction
- •7.2 MapReduce
- •7.3 P2P-MapReduce
- •7.3.1 Architecture
- •7.3.2 Implementation
- •7.3.2.1 Basic Mechanisms
- •Resource Discovery
- •Network Maintenance
- •Job Submission and Failure Recovery
- •7.3.2.2 State Diagram and Software Modules
- •7.3.3 Evaluation
- •7.4 Conclusions
- •References
- •8.1 Introduction
- •8.2 The Cloud Evolution
- •8.3 Improved Network Support for Cloud Computing
- •8.3.1 Why the Internet is Not Enough?
- •8.3.2 Transparent Optical Networks for Cloud Applications: The Dedicated Bandwidth Paradigm
- •8.4 Architecture and Implementation Details
- •8.4.1 Traffic Management and Control Plane Facilities
- •8.4.2 Service Plane and Interfaces
- •8.4.2.1 Providing Network Services to Cloud-Computing Infrastructures
- •8.4.2.2 The Cloud Operating System–Network Interface
- •8.5.1 The Prototype Details
- •8.5.1.1 The Underlying Network Infrastructure
- •8.5.1.2 The Prototype Cloud Network Control Logic and its Services
- •8.5.2 Performance Evaluation and Results Discussion
- •8.6 Related Work
- •8.7 Conclusions
- •References
- •9.1 Introduction
- •9.2 Overview of YML
- •9.3 Design and Implementation of YML-PC
- •9.3.1 Concept Stack of Cloud Platform
- •9.3.2 Design of YML-PC
- •9.3.3 Core Design and Implementation of YML-PC
- •9.4 Primary Experiments on YML-PC
- •9.4.1 YML-PC Can Be Scaled Up Very Easily
- •9.4.2 Data Persistence in YML-PC
- •9.4.3 Schedule Mechanism in YML-PC
- •9.5 Conclusion and Future Work
- •References
- •10.1 Introduction
- •10.2 Related Work
- •10.2.1 General View of Cloud Computing frameworks
- •10.2.2 Cloud Computing Middleware
- •10.3 Deploying Applications in the Cloud
- •10.3.1 Benchmarking the Cloud
- •10.3.2 The ProActive GCM Deployment
- •10.3.3 Technical Solutions for Deployment over Heterogeneous Infrastructures
- •10.3.3.1 Virtual Private Network (VPN)
- •10.3.3.2 Amazon Virtual Private Cloud (VPC)
- •10.3.3.3 Message Forwarding and Tunneling
- •10.3.4 Conclusion and Motivation for Mixing
- •10.4 Moving HPC Applications from Grids to Clouds
- •10.4.1 HPC on Heterogeneous Multi-Domain Platforms
- •10.4.2 The Hierarchical SPMD Concept and Multi-level Partitioning of Numerical Meshes
- •10.4.3 The GCM/ProActive-Based Lightweight Framework
- •10.4.4 Performance Evaluation
- •10.5 Dynamic Mixing of Clusters, Grids, and Clouds
- •10.5.1 The ProActive Resource Manager
- •10.5.2 Cloud Bursting: Managing Spike Demand
- •10.5.3 Cloud Seeding: Dealing with Heterogeneous Hardware and Private Data
- •10.6 Conclusion
- •References
- •11.1 Introduction
- •11.2 Background
- •11.2.1 ASKALON
- •11.2.2 Cloud Computing
- •11.3 Resource Management Architecture
- •11.3.1 Cloud Management
- •11.3.2 Image Catalog
- •11.3.3 Security
- •11.4 Evaluation
- •11.5 Related Work
- •11.6 Conclusions and Future Work
- •References
- •12.1 Introduction
- •12.2 Layered Peer-to-Peer Cloud Provisioning Architecture
- •12.4.1 Distributed Hash Tables
- •12.4.2 Designing Complex Services over DHTs
- •12.5 Cloud Peer Software Fabric: Design and Implementation
- •12.5.1 Overlay Construction
- •12.5.2 Multidimensional Query Indexing
- •12.5.3 Multidimensional Query Routing
- •12.6 Experiments and Evaluation
- •12.6.1 Cloud Peer Details
- •12.6.3 Test Application
- •12.6.4 Deployment of Test Services on Amazon EC2 Platform
- •12.7 Results and Discussions
- •12.8 Conclusions and Path Forward
- •References
- •13.1 Introduction
- •13.2 High-Throughput Science with the Nimrod Tools
- •13.2.1 The Nimrod Tool Family
- •13.2.2 Nimrod and the Grid
- •13.2.3 Scheduling in Nimrod
- •13.3 Extensions to Support Amazon’s Elastic Compute Cloud
- •13.3.1 The Nimrod Architecture
- •13.3.2 The EC2 Actuator
- •13.3.3 Additions to the Schedulers
- •13.4.1 Introduction and Background
- •13.4.2 Computational Requirements
- •13.4.3 The Experiment
- •13.4.4 Computational and Economic Results
- •13.4.5 Scientific Results
- •13.5 Conclusions
- •References
- •14.1 Using the Cloud
- •14.1.1 Overview
- •14.1.2 Background
- •14.1.3 Requirements and Obligations
- •14.1.3.1 Regional Laws
- •14.1.3.2 Industry Regulations
- •14.2 Cloud Compliance
- •14.2.1 Information Security Organization
- •14.2.2 Data Classification
- •14.2.2.1 Classifying Data and Systems
- •14.2.2.2 Specific Type of Data of Concern
- •14.2.2.3 Labeling
- •14.2.3 Access Control and Connectivity
- •14.2.3.1 Authentication and Authorization
- •14.2.3.2 Accounting and Auditing
- •14.2.3.3 Encrypting Data in Motion
- •14.2.3.4 Encrypting Data at Rest
- •14.2.4 Risk Assessments
- •14.2.4.1 Threat and Risk Assessments
- •14.2.4.2 Business Impact Assessments
- •14.2.4.3 Privacy Impact Assessments
- •14.2.5 Due Diligence and Provider Contract Requirements
- •14.2.5.1 ISO Certification
- •14.2.5.2 SAS 70 Type II
- •14.2.5.3 PCI PA DSS or Service Provider
- •14.2.5.4 Portability and Interoperability
- •14.2.5.5 Right to Audit
- •14.2.5.6 Service Level Agreements
- •14.2.6 Other Considerations
- •14.2.6.1 Disaster Recovery/Business Continuity
- •14.2.6.2 Governance Structure
- •14.2.6.3 Incident Response Plan
- •14.3 Conclusion
- •Bibliography
- •15.1.1 Location of Cloud Data and Applicable Laws
- •15.1.2 Data Concerns Within a European Context
- •15.1.3 Government Data
- •15.1.4 Trust
- •15.1.5 Interoperability and Standardization in Cloud Computing
- •15.1.6 Open Grid Forum’s (OGF) Production Grid Interoperability Working Group (PGI-WG) Charter
- •15.1.7.1 What will OCCI Provide?
- •15.1.7.2 Cloud Data Management Interface (CDMI)
- •15.1.7.3 How it Works
- •15.1.8 SDOs and their Involvement with Clouds
- •15.1.10 A Microsoft Cloud Interoperability Scenario
- •15.1.11 Opportunities for Public Authorities
- •15.1.12 Future Market Drivers and Challenges
- •15.1.13 Priorities Moving Forward
- •15.2 Conclusions
- •References
- •16.1 Introduction
- •16.2 Cloud Computing (‘The Cloud’)
- •16.3 Understanding Risks to Cloud Computing
- •16.3.1 Privacy Issues
- •16.3.2 Data Ownership and Content Disclosure Issues
- •16.3.3 Data Confidentiality
- •16.3.4 Data Location
- •16.3.5 Control Issues
- •16.3.6 Regulatory and Legislative Compliance
- •16.3.7 Forensic Evidence Issues
- •16.3.8 Auditing Issues
- •16.3.9 Business Continuity and Disaster Recovery Issues
- •16.3.10 Trust Issues
- •16.3.11 Security Policy Issues
- •16.3.12 Emerging Threats to Cloud Computing
- •16.4 Cloud Security Relationship Framework
- •16.4.1 Security Requirements in the Clouds
- •16.5 Conclusion
- •References
- •17.1 Introduction
- •17.1.1 What Is Security?
- •17.2 ISO 27002 Gap Analyses
- •17.2.1 Asset Management
- •17.2.2 Communications and Operations Management
- •17.2.4 Information Security Incident Management
- •17.2.5 Compliance
- •17.3 Security Recommendations
- •17.4 Case Studies
- •17.4.1 Private Cloud: Fortune 100 Company
- •17.4.2 Public Cloud: Amazon.com
- •17.5 Summary and Conclusion
- •References
- •18.1 Introduction
- •18.2 Decoupling Policy from Applications
- •18.2.1 Overlap of Concerns Between the PEP and PDP
- •18.2.2 Patterns for Binding PEPs to Services
- •18.2.3 Agents
- •18.2.4 Intermediaries
- •18.3 PEP Deployment Patterns in the Cloud
- •18.3.1 Software-as-a-Service Deployment
- •18.3.2 Platform-as-a-Service Deployment
- •18.3.3 Infrastructure-as-a-Service Deployment
- •18.3.4 Alternative Approaches to IaaS Policy Enforcement
- •18.3.5 Basic Web Application Security
- •18.3.6 VPN-Based Solutions
- •18.4 Challenges to Deploying PEPs in the Cloud
- •18.4.1 Performance Challenges in the Cloud
- •18.4.2 Strategies for Fault Tolerance
- •18.4.3 Strategies for Scalability
- •18.4.4 Clustering
- •18.4.5 Acceleration Strategies
- •18.4.5.1 Accelerating Message Processing
- •18.4.5.2 Acceleration of Cryptographic Operations
- •18.4.6 Transport Content Coding
- •18.4.7 Security Challenges in the Cloud
- •18.4.9 Binding PEPs and Applications
- •18.4.9.1 Intermediary Isolation
- •18.4.9.2 The Protected Application Stack
- •18.4.10 Authentication and Authorization
- •18.4.11 Clock Synchronization
- •18.4.12 Management Challenges in the Cloud
- •18.4.13 Audit, Logging, and Metrics
- •18.4.14 Repositories
- •18.4.15 Provisioning and Distribution
- •18.4.16 Policy Synchronization and Views
- •18.5 Conclusion
- •References
- •19.1 Introduction and Background
- •19.2 A Media Service Cloud for Traditional Broadcasting
- •19.2.1 Gridcast the PRISM Cloud 0.12
- •19.3 An On-demand Digital Media Cloud
- •19.4 PRISM Cloud Implementation
- •19.4.1 Cloud Resources
- •19.4.2 Cloud Service Deployment and Management
- •19.5 The PRISM Deployment
- •19.6 Summary
- •19.7 Content Note
- •References
- •20.1 Cloud Computing Reference Model
- •20.2 Cloud Economics
- •20.2.1 Economic Context
- •20.2.2 Economic Benefits
- •20.2.3 Economic Costs
- •20.2.5 The Economics of Green Clouds
- •20.3 Quality of Experience in the Cloud
- •20.4 Monetization Models in the Cloud
- •20.5 Charging in the Cloud
- •20.5.1 Existing Models of Charging
- •20.5.1.1 On-Demand IaaS Instances
- •20.5.1.2 Reserved IaaS Instances
- •20.5.1.3 PaaS Charging
- •20.5.1.4 Cloud Vendor Pricing Model
- •20.5.1.5 Interprovider Charging
- •20.6 Taxation in the Cloud
- •References
- •21.1 Introduction
- •21.2 Background
- •21.3 Experiment
- •21.3.1 Target Application: Value at Risk
- •21.3.2 Target Systems
- •21.3.2.1 Condor
- •21.3.2.2 Amazon EC2
- •21.3.2.3 Eucalyptus
- •21.3.3 Results
- •21.3.4 Job Completion
- •21.3.5 Cost
- •21.4 Conclusions and Future Work
- •References
- •Index
Preface
Introduction
Cloud computing appears to have emerged very recently as a subject of substantial industrial and academic interest, though its meaning, scope and fit with respect to other paradigms is hotly debated. For some researchers, Clouds are a natural evolu- tion towards full commercialisation of Grid systems, while for others they may be dismissed as a mere rebranding of the existing pay-per-use or pay-as-you-go technologies. From either perspective, it appears that ‘Cloud’ has become the label of choice for accountable pay-per-use access to a wide variety of third-party applications and computational resources on a massive scale. Clouds are now supporting patterns of less-predictable resource use for applications and services across the IT spectrum, from online office applications to high-throughput transactional services and high-performance computations involving substantial quantities of processing cycles and storage. The current notion of Clouds seems to blur the distinctions between Grid Services, Web Services, and data centres, amongst others, and brings considerations of lowering the cost for relatively bursty applications to the fore.
Currently, there appears to be an increasing demand for Cloud computing in general. Major IT and e-commerce vendors such as Amazon, Google, IBM,
Microsoft, and Sun have joined a variety of technology and service providers in offering Clouds. In turn, this generates significant demand for reference materials that provide coverage for this topic, ranging from standard developer guides to advanced expositions of research into Cloud design, optimisation and management. Interest in Cloud computing, as a concept or system design abstraction, is compounded and further strengthened by an inherent relationship to service-oriented computing. Clouds may be considered by some as a reincarnation and an extension of service-oriented computing that covers computational hardware-based resources as well as software, with concomitant business benefits in cost reduction where such services scale efficiently.
For the scientific community, Cloud computing offers interesting characteristics and challenges. Some of these exist at the intersection between computing and economics, where the key question is how to develop a Cloud infrastructure that provides the required quality of service; from a network economics perspective,
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this relates to the design and deployment of an adaptive pricing mechanism that provides both for a competitive edge and a profitable venture. At the same time, end-users (both potential consumers and providers) need to be able to understand the similarities, differences, benefits and disadvantages of Clouds over numerous existing paradigms including Grids, High-Performance Computing, Peer-to-Peer (P2P) systems and so on. P2P, Grid, High-Performance Computing and Web
Services are very pertinent fields that have received significant and sustained research interest in the design and deployment of large-scale and high-performance computational resource-sharing systems. Collectively, these form the de facto basis for methods and techniques that will be re-appraised, re-used or re-designed to construct performance-driven Cloud platforms capable of satisfying the four cor- nerstones of quality of service:
1.Efficiency: The execution and coordination of the services is optimised in terms of data traffic and latency. Data traffic is typically one of the main cost factors in any distributed computing framework and thus its reduction is a standard long- term goal of such systems. Latency is arguably one of the most important factors affecting customer satisfaction and therefore it should also be within specified acceptable limits.
2.Scalability: These platforms should scale well to massive customer bases. They must also withstand demand of multiple bursty applications during peak times and endure the ‘flash crowds’ phenomenon familiar in overly successful marketing strategies and provisioning for popular websites at key times.
3.Robustness: The services need continuously high availability by design, with effective use of redundancy and graceful failover. Where users are charged for the expected successful use of computational facilities, it is imperative to understand the risk of failure, either to remove the probability of failure, or to use this information to offer appropriate compensation schemes.
4.Security:Appropriatesecurityprovisionsmustexistforbothdataandapplicationsto protect both the providers and consumers from malicious or fraudulent activities. Without adequate security provisioning, it is highly unlikely that any commoditised platform would become a serious consideration for business computing.
To ensure commercial success, effective Clouds will be expected to provide guaranteed quality of service to customers by satisfying these four cornerstones.
This book is targeted at providing a thorough and advanced treatment of the state-of-the-art in Cloud computing that addresses the above topics and highlights and clarifies the conceptual and systemic links with other distributed computing approaches.
The book has four key objectives:
(i)To explore the relationship of Cloud computing to other distributed computing paradigms, namely Peer-to-Peer, Grids, High-Performance Computing and
Web Services
(ii)To present the principles, techniques, protocols and algorithms that can be adapted from other distributed computing paradigms to the development of successful Clouds
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(iii)to present current Cloud applications and highlight early deployment experiences
(iv)to elaborate the economic schemes needed for Clouds to become viable business models.
The first two objectives are firmly rooted in extant discourse of distributed computing and a desire to understand the potential of all these technologies in constructing purpose-specific hybrid solutions. The remaining objectives are closely linked to commercial demand for understanding how such technologies can shape successful and profitable businesses.
Expected Audience
This book should be of particular interest for the following audiences:
•Researchers and doctoral students working specifically in Cloud computing research, implementation and deployment, primarily as a reference publication. Similarly, this book should be useful to researchers in related, or more general fields, such as distributed computing, software engineering, Web Services, modelling of business processes, and so on.
•Academics and students engaging in research-informed teaching in the above fields. This book can serve as a good collection of articles to facilitate a broad understanding of this subject and as such may be useful as a key reference text in such teaching.
•Professional system architects and developers who could decide to adapt and apply in practice a number of the techniques and processes presented in the book.
•Technical managers and IT consultants as a book that demonstrates the potential applicability of certain methods for delivering efficient and secure commercial electronic services to customers globally.
These audiences will find this publication appealing as it combines three distinct scholarly contributions: first, it identifies and highlights state-of-the-art techniques and methods for designing Cloud systems; second, it presents mechanisms and schemes for linking Clouds to economic activities; third, it achieves balanced coverage of all related technologies that collectively contribute towards the realisation of Cloud computing.
Book Overview
The book contains 21 chapters that were carefully selected based on peer review by at least two expert and independent reviewers. The chapters are split into four Parts:
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Part 1: Cloud Base
This section aims to cover the essential definitions, characteristics and concepts behind Cloud computing. The chapters included in this section collectively introduce the reader to Cloud computing and its essential architectural principles. As a result, chapters in this section are either tutorial in nature or provide critical literature surveys in the field.
Chapter 1 presents a number of mainstream technologies for building and managing Cloud architectures. The authors provide a detailed description of virtual machine frameworks and present the MapReduce programming model, which is suitable for large-scale data processing.
Chapter 2 describes a detailed taxonomy of Cloud computing architectures that may promote clarity and reusability of key concepts in Cloud design. The authors use this taxonomy to identify key similarities and differences between various approaches to Cloud computing and underline areas for further development.
Chapter 3 analyses the applicability of Cloud computing in e-Science. It focuses on classifying different Cloud architectures in terms of their ability to provide the services required for large-scale scientific experiments and calculations.
Chapter 4 examines the differences between Cloud and Grid computing. The authors explain how the userand task-centric design philosophy of Clouds makes this technology more appealing to typical end-users.
Chapter 5 provides a high-level overview of various standards for, and related to, Cloud computing. It explores the key features of each standard in terms of interoperability, security and portability and assesses the potential for market adoption of the standards presented.
Part 2: Cloud Seeding
This section builds on the introductory material of Part 1 and provides in-depth coverage of how Clouds can be designed and how emerging technologies such as P2P fit with Cloud computing in general. It includes chapters that propose novel techniques and systems for making Clouds scalable, efficient and fault-tolerant computing platforms.
Chapter 6 presents an innovative computational paradigm called Cloud@Home that merges Peer-to-Peer computing with Clouds. The Cloud@Home aggregates the computational resources of many low-power systems, and the authors demonstrate how this pool of resources can subsequently be managed and used by different communities of users.
Chapter 7 exploits a novel peer-to-peer model for replicating and managing job states in an efficient and decentralised way. The authors use this model to enhance the fault tolerance of the MapReduce programming paradigm in highly dynamic environments that exhibit significant failure rates.