Architecting the Cloud

Foreword xiii

Preface xv

Acknowledgments xix

About the author xxi

Chapter 1 Why Cloud, Why Now? 1

Evolution of Cloud Computing 3

Enter the Cloud 6

Start-Up Case Study: Instagram, from Zero to a Billion Overnight 8

Established Company Case Study: Netflix, Shifting from On-Premises to the Cloud 9

Government Case Study: NOAA, E-mail, and Collaboration in the Cloud 10

Not-for-Profit Case Study: Obama Campaign, Six-Month Shelf-Life with One Big Peak 10

Summary 11

Chapter 2 Cloud Service Models 13

Infrastructure as a Service 13

Platform as a Service 15

Software as a Service 17

Deployment Models 18

Summary 22

Chapter 3 Cloud Computing Worst Practices 23

Avoiding Failure When Moving to the Cloud 23

Migrating Applications to the Cloud 23

Misguided Expectations 27

Misinformed about Cloud Security 29

Selecting a Favorite Vendor, Not an Appropriate Vendor 31

Outages and Out-of-Business Scenarios 31

Underestimating the Impacts of Organizational Change 33

Skills Shortage 35

Misunderstanding Customer Requirements 36

Unexpected Costs 37

Summary 39

Chapter 4 It Starts with Architecture 41

The Importance of Why, Who, What, Where, When, and How 41

Start with the Business Architecture 43

Identify the Problem Statement (Why) 47

Evaluate User Characteristics (Who) 48

Identify Business and Technical Requirements (What) 48

Visualize the Service Consumer Experience (Where) 49

Identify the Project Constraints (When and with What) 51

Understand Current State Constraints (How) 52

Summary 54

Chapter 5 Choosing the Right Cloud Service Model 55

Considerations when Choosing a Cloud Service Model 56

When to Use SaaS 59

When to Use PaaS 62

When to Use IaaS 65

Common Cloud Use Cases 68

Summary 69

Chapter 6 The Key to the Cloud: RESTful Services 71

Why REST? 72

The Challenges of Migrating Legacy Systems to the Cloud 74

Summary 75

Chapter 7 Auditing in the Cloud 77

Data and Cloud Security 78

Auditing Cloud Applications 78

Regulations in the Cloud 80

Audit Design Strategies 83

Summary 85

Chapter 8 Data Considerations in the Cloud 87

Data Characteristics 87

Multitenant or Single Tenant 92

Choosing Data Store Types 95

Summary 98

Chapter 9 Security Design in the Cloud 99

The Truth about Data in the Cloud 100

How Much Security Is Required 101

Responsibilities for Each Cloud Service Model 104

Security Strategies 108

Areas of Focus 110

Summary 118

Chapter 10 Creating a Centralized Logging Strategy 119

Log File Uses 119

Logging Requirements 120

Summary 124

Chapter 11 SLA Management 127

Factors That Impact SLAs 127

Defining SLAs 130

Managing Vendor SLAs 132

Summary 135

Chapter 12 Monitoring Strategies 137

Proactive vs. Reactive Monitoring 137

What Needs to Be Monitored? 138

Monitoring Strategies by Category 139

Monitoring by Cloud Service Level 145

Summary 147

Chapter 13 Disaster Recovery Planning 149

What Is the Cost of Downtime? 149

Disaster Recovery Strategies for IaaS 151

Recovering from a Disaster in the Primary Data Center 152

Disaster Recovery Strategies for PaaS 157

Disaster Recovery Strategies for SaaS 159

Disaster Recovery Hybrid Clouds 160

Summary 162

Chapter 14 Leveraging a DevOps Culture to Deliver Software Faster and More Reliably 163

Developing the DevOps Mind-Set 163

Automate Infrastructure 165

Automate Deployments 166

Design Feature Flags 167

Measure, Monitor, and Experiment 167

Continuous Integration and Continuous Delivery 168

Summary 170

Chapter 15 Assessing the Organizational Impact of the Cloud Model 171

Enterprise Model vs. Elastic Cloud Model 172

IT Impact 173

Business Impacts 174

Organization Change Planning 178

Change in the Real World 180

Summary 181

Chapter 16 Final Thoughts 183

The Cloud Is Evolving Rapidly 183

Cloud Culture 185

New Business Models 186

PaaS Is the Game Changer 187

Summary 190

Index 193