Cloud Computing

Thomas Erl is a top-selling IT author, founder of Arcitura Education, editor of the Service Technology Magazine and series editor of the Prentice Hall Service Technology Series from Thomas Erl. With more than 175,000 copies in print world-wide, his books have become international bestsellers and have been formally endorsed by senior members of major IT organizations, such as IBM, Microsoft, Oracle, Intel, Accenture, IEEE, HL7, MITRE, SAP, CISCO, HP, and many others. As CEO of Arcitura Education Inc. and in cooperation with CloudSchool.com and SOASchool.com, Thomas has led the development of curricula for the internationally recognized Cloud Certified Professional (CCP) and SOA Certified Professional (SOACP) accreditation programs, which have established a series of formal, vendor-neutral industry certifications obtained by thousands of IT professionals around the world. Thomas has toured over 20 countries as a speaker and instructor and regularly participates in international conferences, including Service Technology Symposium and Gartner events. More than 100 articles and interviews by Thomas have been published in numerous publications, including The Wall Street Journal and CIO Magazine. Dr. Zaigham Mahmood is a published author of six books, four of which are dedicated to cloud computing. He acts as a technology consultant at Debesis Education UK and a Researcher at the University of Derby, UK. He further holds positions as a foreign professor and professor extraordinaire with international educational institutions. Professor Mahmood is a certified cloud trainer and a regular speaker at the International SOA, Cloud + Service Technology Symposium, and he has published more than 100 articles. His specialized areas of research include distributed computing, project management, and e-government. Professor Ricardo Puttini has 15 years of field experience as a senior IT consultant at major government organizations in Brazil. He has taught several undergraduate and graduate-level courses in service orientation, service-oriented architecture, and cloud computing. Ricardo was the general chair of the 4th International SOA Symposium and 3rd International Cloud Symposium that was held in the spring of 2011. He holds a Ph.D. in Communication Networks (2004) from the University of Brasilia, where he has taught in the Electrical Engineering department since 1998. Ricardo spent 18 months at the L′Ecole Superieure d′Electricite (Supelec) in Rennes, France, during his Ph.D., where he started researching distributed system architecture and security.  

Foreword     xxix

Acknowledgments     xxxiii

CHAPTER 1: Introduction     1

1.1 Objectives of This Book     3

1.2 What This Book Does Not Cover     4

1.3 Who This Book Is For     4

1.4 How This Book Is Organized     4

1.5 Conventions     9

Symbols and Figures     9

Summary of Key Points     9

1.6 Additional Information     9

Updates, Errata, and Resources (www.servicetechbooks.com)      9

Referenced Specifications (www.servicetechspecs.com)      10

The Service Technology Magazine (www.servicetechmag.com)      10

International Service Technology Symposium (www.servicetechsymposium.com)      10

What Is Cloud? (www.whatiscloud.com)      10

What Is REST? (www.whatisrest.com)      10

Cloud Computing Design Patterns (www.cloudpatterns.org)      10

Service-Orientation (www.serviceorientation.com)      11

CloudSchool.com Certified Cloud (CCP) Professional (www.cloudschool.com)      11

SOASchool.com SOA Certified (SOACP) Professional (www.soaschool.com)      11

Notification Service     11

CHAPTER 2: Case Study Background     13

2.1 Case Study #1: ATN     14

Technical Infrastructure and Environment     14

Business Goals and New Strategy     15

Roadmap and Implementation Strategy     15

2.2 Case Study #2: DTGOV     16

Technical Infrastructure and Environment     17

Business Goals and New Strategy     18

Roadmap and Implementation Strategy     19

2.3 Case Study #3: Innovartus Technologies Inc     20

Technical Infrastructure and Environment     20

Business Goals and Strategy     20

Roadmap and Implementation Strategy     21

PART I: FUNDAMENTAL CLOUD COMPUTING

CHAPTER 3: Understanding Cloud Computing     25

3.1 Origins and Influences     26

A Brief History     26

Definitions     27

Business Drivers     28

Capacity Planning     28

Cost Reduction     29

Organizational Agility     30

Technology Innovations     30

Clustering     31

Grid Computing     31

Virtualization     32

Technology Innovations vs. Enabling Technologies     32

3.2 Basic Concepts and Terminology     33

Cloud     33

IT Resource     34

On-Premise     36

Cloud Consumers and Cloud Providers     36

Scaling     37

Horizontal Scaling     37

Vertical Scaling     37

Cloud Service     38

Cloud Service Consumer      40

3.3 Goals and Benefits     40

Reduced Investments and Proportional Costs     41

Increased Scalability     42

Increased Availability and Reliability     43

3.4 Risks and Challenges     45

Increased Security Vulnerabilities     45

Reduced Operational Governance Control     45

Limited Portability Between Cloud Providers     47

Multi-Regional Compliance and Legal Issues     48

CHAPTER 4: Fundamental Concepts and Models     51

4.1 Roles and Boundaries     52

Cloud Provider     52

Cloud Consumer     52

Cloud Service Owner     53

Cloud Resource Administrator     54

Additional Roles     56

Organizational Boundary     56

Trust Boundary     57

4.2 Cloud Characteristics     58

On-Demand Usage     59

Ubiquitous Access     59

Multitenancy (and Resource Pooling)      59

Elasticity     61

Measured Usage     61

Resiliency     61

4.3 Cloud Delivery Models     63

Infrastructure-as-a-Service (IaaS)      64

Platform-as-a-Service (PaaS)      65

Software-as-a-Service (SaaS)      66

Comparing Cloud Delivery Models     67

Combining Cloud Delivery Models     69

IaaS + PaaS     69

IaaS + PaaS + SaaS     72

4.4 Cloud Deployment Models     73

Public Clouds     73

Community Clouds     74

Private Clouds     75

Hybrid Clouds     77

Other Cloud Deployment Models     78

CHAPTER 5: Cloud-Enabling Technology     79

5.1 Broadband Networks and Internet Architecture     80

Internet Service Providers (ISPs)      80

Connectionless Packet Switching (Datagram Networks)      83

Router-Based Interconnectivity     83

Physical Network     84

Transport Layer Protocol      84

Application Layer Protocol     85

Technical and Business Considerations     85

Connectivity Issues     85

Network Bandwidth and Latency Issues     88

Cloud Carrier and Cloud Provider Selection     89

5.2 Data Center Technology     90

Virtualization     90

Standardization and Modularity     90

Automation     91

Remote Operation and Management     92

High Availability     92

Security-Aware Design, Operation, and Management     92

Facilities     92

Computing Hardware     93

Storage Hardware     93

Network Hardware     95

Carrier and External Networks Interconnection     95

Web-Tier Load Balancing and Acceleration     95

LAN Fabric     95

SAN Fabric     95

NAS Gateways     95

Other Considerations     96

5.3 Virtualization Technology     97

Hardware Independence     98

Server Consolidation     98

Resource Replication     98

Operating System-Based Virtualization     99

Hardware-Based Virtualization     101

Virtualization Management     102

Other Considerations     102

5.4 Web Technology     103

Basic Web Technology     104

Web Applications     104

5.5 Multitenant Technology     106

5.6 Service Technology     108

Web Services     109

REST Services     110

Service Agents     111

Service Middleware     112

5.7 Case Study Example     113

CHAPTER 6: Fundamental Cloud Security     117

6.1 Basic Terms and Concepts     118

Confidentiality     118

Integrity     119

Authenticity     119

Availability     119

Threat     120

Vulnerability     120

Risk     120

Security Controls     120

Security Mechanisms     121

Security Policies     121

6.2 Threat Agents     121

Anonymous Attacker     122

Malicious Service Agent     123

Trusted Attacker     123

Malicious Insider     123

6.3 Cloud Security Threats     124

Traffic Eavesdropping     124

Malicious Intermediary     124

Denial of Service     126

Insufficient Authorization     127

Virtualization Attack     127

Overlapping Trust Boundaries     129

6.4 Additional Considerations     131

Flawed Implementations     131

Security Policy Disparity     132

Contracts     132

Risk Management     133

6.5 Case Study Example     135

PART II: CLOUD COMPUTING MECHANISMS

CHAPTER 7: Cloud Infrastructure Mechanisms     139

7.1 Logical Network Perimeter     140

Case Study Example     142

7.2 Virtual Server     144

Case Study Example     145

7.3 Cloud Storage Device     149

Cloud Storage Levels     149

Network Storage Interfaces     150

Object Storage Interfaces     151

Database Storage Interfaces     151

Relational Data Storage     151

Non-Relational Data Storage     152

Case Study Example     152

7.4 Cloud Usage Monitor     155

Monitoring Agent     155

Resource Agent     155

Polling Agent     157

Case Study Example     157

7.5 Resource Replication     161

Case Study Example     162

7.6 Ready-Made Environment     166

Case Study Example     167

CHAPTER 8: Specialized Cloud Mechanisms     169

8.1 Automated Scaling Listener     170

Case Study Example     172

8.2 Load Balancer     176

Case Study Example     177

8.3 SLA Monitor     178

Case Study Example     180

SLA Monitor Polling Agent     180

SLA Monitoring Agent     180

8.4 Pay-Per-Use Monitor     184

Case Study Example     187

8.5 Audit Monitor     189

Case Study Example     189

8.6 Failover System     191

Active-Active     191

Active-Passive     194

Case Study Example     196

8.7 Hypervisor     200

Case Study Example     201

8.8 Resource Cluster     203

Case Study Example     206

8.9 Multi-Device Broker     208

Case Study Example     209

8.10 State Management Database     210

Case Study Example     211

CHAPTER 9: Cloud Management Mechanisms     213

9.1 Remote Administration System     214

Case Study Example     219

9.2 Resource Management System     219

Case Study Example     221

9.3 SLA Management System     222

Case Study Example     224

9.4 Billing Management System     225

Case Study Example     227

CHAPTER 10: Cloud Security Mechanisms     229

10.1 Encryption     230

Symmetric Encryption     231

Asymmetric Encryption     231

Case Study Example     233

10.2 Hashing     234

Case Study Example     235

10.3 Digital Signature     236

Case Study Example     238

10.4 Public Key Infrastructure (PKI)      240

Case Study Example     242

10.5 Identity and Access Management (IAM)      243

Case Study Example     244

10.6 Single Sign-On (SSO)      244

Case Study Example     246

10.7 Cloud-Based Security Groups     247

Case Study Example     249

10.8 Hardened Virtual Server Images     251

Case Study Example     252

PART III: CLOUD COMPUTING ARCHITECTURE

CHAPTER 11: Fundamental Cloud Architectures     255

11.1 Workload Distribution Architecture     256

11.2 Resource Pooling Architecture     257

11.3 Dynamic Scalability Architecture     262

11.4 Elastic Resource Capacity Architecture     265

11.5 Service Load Balancing Architecture     268

11.6 Cloud Bursting Architecture     271

11.7 Elastic Disk Provisioning Architecture     272

11.8 Redundant Storage Architecture     275

11.9 Case Study Example     277

CHAPTER 12: Advanced Cloud Architectures     281

12.1 Hypervisor Clustering Architecture     282

12.2 Load Balanced Virtual Server Instances Architecture     288

12.3 Non-Disruptive Service Relocation Architecture     293

12.4 Zero Downtime Architecture     298

12.5 Cloud Balancing Architecture     299

12.6 Resource Reservation Architecture     301

12.7 Dynamic Failure Detection and Recovery Architecture     306

12.8 Bare-Metal Provisioning Architecture     309

12.9 Rapid Provisioning Architecture     312

12.10 Storage Workload Management Architecture     315

12.11 Case Study Example     321

CHAPTER 13: Specialized Cloud Architectures     323

13.1 Direct I/O Access Architecture     324

13.2 Direct LUN Access Architecture     326

13.3 Dynamic Data Normalization Architecture     329

13.4 Elastic Network Capacity Architecture     330

13.5 Cross-Storage Device Vertical Tiering Architecture     332

13.6 Intra-Storage Device Vertical Data Tiering Architecture     337

13.7 Load Balanced Virtual Switches Architecture     340

13.8 Multipath Resource Access Architecture     342

13.9 Persistent Virtual Network Configuration Architecture     344

13.10 Redundant Physical Connection for Virtual Servers Architecture     347

13.11 Storage Maintenance Window Architecture     350

PART IV: WORKING WITH CLOUDS

CHAPTER 14: Cloud Delivery Model Considerations     359

14.1 Cloud Delivery Models: The Cloud Provider Perspective     360

Building IaaS Environments     360

Data Centers     361

Scalability and Reliability     363

Monitoring     363

Security     364

Equipping PaaS Environments     364

Scalability and Reliability     365

Monitoring     367

Security     367

Optimizing SaaS Environments     367

Security     370

14.2 Cloud Delivery Models: The Cloud Consumer Perspective     370

Working with IaaS Environments     370

IT Resource Provisioning Considerations     372

Working with PaaS Environments     373

IT Resource Provisioning Considerations     373

Working with SaaS Services     374

14.3 Case Study Example     375

CHAPTER 15: Cost Metrics and Pricing Models     379

15.1 Business Cost Metrics     380

Up-Front and On-Going Costs     380

Additional Costs     381

Case Study Example     382

Product Catalog Browser     382

On-Premise Up-Front Costs     382

On-Premise On-Going Costs     383

Cloud-Based Up-Front Costs     383

Cloud-Based On-Going Costs     383

Client Database     385

On-Premise Up-Front Costs     385

On-Premise On-Going Costs     385

Cloud-Based Up-Front Costs     385

Cloud-Based On-Going Costs     385

15.2 Cloud Usage Cost Metrics     387

Network Usage     387

Inbound Network Usage Metric     387

Outbound Network Usage Metric     388

Intra-Cloud WAN Usage Metric     388

Server Usage     389

On-Demand Virtual Machine Instance Allocation Metric     389

Reserved Virtual Machine Instance Allocation Metric     389

Cloud Storage Device Usage     390

On-Demand Storage Space Allocation Metric     390

I/O Data Transferred Metric     390

Cloud Service Usage     390

Application Subscription Duration Metric     390

Number of Nominated Users Metric     391

Number of Transactions Users Metric      391

15.3 Cost Management Considerations     391

Pricing Models     393

Additional Considerations     395

Case Study Example     396

Virtual Server On-Demand Instance Allocation     397

Virtual Server Reserved Instance Allocation     399

Cloud Storage Device     401

WAN Traffic     401

CHAPTER 16: Service Quality Metrics and SLAs     403

16.1 Service Quality Metrics     404

Service Availability Metrics     405

Availability Rate Metric     405

Outage Duration Metric     406

Service Reliability Metrics     407

Mean-Time Between Failures (MTBF) Metric     407

Reliability Rate Metric     407

Service Performance Metrics     407

Network Capacity Metric     408

Storage Device Capacity Metric     408

Server Capacity Metric     408

Web Application Capacity Metric     408

Instance Starting Time Metric     409

Response Time Metric     409

Completion Time Metric     409

Service Scalability Metrics     409

Storage Scalability (Horizontal) Metric     410

Server Scalability (Horizontal) Metric     410

Server Scalability (Vertical) Metric     410

Service Resiliency Metrics     411

Mean-Time to Switchover (MTSO) Metric     411

Mean-Time System Recovery (MTSR) Metric     412

16.2 Case Study Example     412

16.3 SLA Guidelines     413

16.4 Case Study Example     416

Scope and Applicability     416

Service Quality Guarantees     416

Definitions     417

Usage of Financial Credits     417

SLA Exclusions     418

PART V: APPENDICES

Appendix A: Case Study Conclusions     421

A.1 ATN     422

A.2 DTGOV     422

A.3 Innovartus     424

Appendix B: Industry Standards Organizations     427

B.1 National Institute of Standards and Technology (NIST)      428

B.2 Cloud Security Alliance (CSA)      429

B.3 Distributed Management Task Force (DMTF)      429

B.4 Storage Networking Industry Association (SNIA)      430

B.5 Organization for the Advancement of Structured Information Standards (OASIS)      430

B.6 The Open Group     430

B.7 Open Cloud Consortium (OCC)      431

B.8 European Telecommunications Standards Institute (ETSI)      431

B.9 Telecommunications Industry Association (TIA)      431

B.10 Liberty Alliance     432

B.11 Open Grid Forum (OGF)      432

Appendix C: Mapping Mechanisms to Characteristics     433

Appendix D: Data Center Facilities (TIA-942)      437

D.1 Primary Rooms     438

Electrical Room     438

Mechanical Room     438

Storage and Staging     438

Offices, Operations Center, and Support     438

Telecommunications Entrance     438

Computer Room     439

D.2 Environmental Controls     440

External Electrical Power Provider Interconnection     440

Power Distribution     441

Uninterruptible Power Source (UPS)      441

Power Engine-Generator     441

D.3 Infrastructure Redundancy Summary     442

Appendix E: Emerging Technologies     443

E.1 Autonomic Computing     444

E.2 Grid Computing     445

Service Grids     446

Appendix F: Cloud Provisioning Contracts     449

F.1 Cloud Provisioning Contract Structure     450

Terms of Service     452

Service Usage Policy     452

Security and Privacy Policy     453

Warranties and Liabilities     455

Rights and Responsibilities     455

Termination and Renewal     456

Specifications and SLAs     456

Pricing and Billing     457

Other Issues     457

Legal and Compliance Issues     457

Auditability and Accountability     457

Changes in the Contract Terms and Conditions     457

F.2 Cloud Provider Selection Guidelines     458

Cloud Provider Viability     458

Appendix G: Cloud Business Case Template     461

G.1 Business Case Identification     462

G.2 Business Needs     462

G.3 Target Cloud Environment     463

G.4 Technical Issues     464

G.5 Economic Factors     464

About the Authors     465

About the Foreword Contributor     467

About the Contributors     469

Index     471