Web Services, Service-Oriented Architectures, and Cloud Computing

245 Pages·2013·8.72 MB·English

by  Douglas K. Barry

Web Services,
Service-Oriented
Architectures, and
Cloud Computing
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Web Services,
Service-Oriented
Architectures, and
Cloud Computing
The Savvy Manager’s Guide
Second Edition
Douglas K. Barry
with
David Dick
AMSTERDAM • BOSTON • HEIDELBERG • LONDON
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Contents
Introduction xv
Part I
Overview of Web Services, Service-Oriented Architecture,
and Cloud Computing 1
1 A Business Trip in the Not-Too-Distant Future 3
The Business Trip 3
Summary 8
2 Information Technology Used for the Business Trip 9
Keeping Track of Detailed Customer Data 10
Using Virtual Personal Assistants 10
Managing C. R.’s Business Trip 12
Augmenting C. R.’s Experiences 12
Commoditizing Services 12
Viewing All Services the Same Way 13
Summary 13
3 Web Services and Service-Oriented Architectures 15
Service-Oriented Architecture Overview 17
Services 17
Connections 18
The Architecture in SOA 18
Web Services Explained 19
History of Web Services Specification 19
Web Services Specifications 22
The Opportunity and Importance of
Standardized Semantic Vocabularies 29
Service-Oriented Architecture Explained 29
Relationship of Web Services and SOA 30
Identification and Design of Services 30
Service-Oriented Architecture 31
Summary 33
v
vi Contents
4 Cloud Computing 35
Blurring of Internal and External Services 37
Organizations of Any Size Can Use a Service-Oriented
Architecture with Cloud Computing 38
The Cloud 39
Types of Clouds 41
Categories of Cloud Providers 42
Summary 44
Part II
Technical Forces Driving the Adoption of Web Services,
Service-Oriented Architectures, and Cloud Computing 45
5 Technical Forces Driving the Adoption of
Web Services 47
Force Field Analysis Overview 48
Adopting Standard Data Element Definitions 50
Adopting a Standard Communications Protocol 51
Adopting Web Services 52
Summary 54
6 Technical Forces Driving the Adoption
of SOA 55
Adopting Standard, Enterprise-Wide Software 56
Adopting an Object Request Broker 57
Adopting an Enterprise Data Warehouse 59
Adopting an Enterprise Service Bus 62
Message Routers 62
Adapters 63
Adopting a Service-Oriented Architecture 67
Summary 70
7 Technical Forces Driving the Adoption of
Cloud Computing 71
Adopting Software as a Service (SaaS) 72
Adopting Platform as a Service (PaaS) 74
Adopting Service-Oriented Architecture with
Cloud Computing 76
Summary 79
Contents vii
Part III
Managing Change Needed for Web Services,
Service-Oriented Architectures, and Cloud Computing 81
8 Change Issues 83
Change 85
Technical Change Issues Diminishing 85
Resistance to Change 85
Forms of Resistance 88
Lack of Training/Understanding 89
Power of Internal “Expert” 89
Inertia—Why Change? 90
Feeling that Jobs May Be Threatened 90
Not Invented Here 91
Our Problems Are Special 91
Loss of Familiarity, Competence, and Control 91
Suggestions for Addressing Resistance to Change 92
Selecting the Right People 92
Use a Second Set of Eyes 93
Really Listen 93
Communicate at Many Levels 94
Seek Appropriate Avenues to Involve People 94
Get Resistance Out in the Open 94
Ask for Participation and Form Partnerships 95
Some Resistance Scenarios 95
But It’s So Complicated! 95
Guerilla Tactics 98
More Guerilla Tactics 100
The Elephant in the Room 101
Worksheet for Resistance Issues and Suggestions 102
Consolidated Analysis for Adopting an SOA with Cloud Computing 102
Summary 105
9 Tips for Managing Change Issues During Development 107
Design as Little as Possible 108
Buy a System or Use One or More Existing Services 108
Buy a Model or Adopt a Semantic Vocabulary 108
Write as Little Code as Possible 109
Reduce Project Scope 110
Use a Methodology 110
viii Contents
Use a Second Set of Eyes 111
Use Small Teams 111
Summary 112
10 Managing Change with Incremental SOA Analysis 113
Tools 114
Force Field Analysis 114
Worksheet for Resistance Issues and Suggestions 114
Decomposition Matrix 115
Five Principles for the Incremental SOA Analysis 121
Incremental SOA Analysis 122
Business Process Analysis Lane 123
Candidate Project Analysis Lane 124
Deployment Selection Lane 125
Select a Project with the Best Chance of Success 125
Deployment Lane 125
Vocabulary Management Lane 126
Summary 127
Part IV
Getting Started with Web Services, Service-Oriented Architectures,
and Cloud Computing 129
11 Getting Started with Web Services 131
All Web Services Connections Look the Same 132
The Impact of Web Services 132
Use of Web Services will Likely Spur Innovation 133
Start by Experimenting with Web Services 133
Use an External Service 133
Develop an Internal Service 134
Exchange Data Between Existing Systems 135
Use an ESB 136
Staffing Issues 137
Likely Change Issues 137
Adapt Existing Systems to Use Web Services 138
Enterprise Database Warehouse 138
Connect Components to Web Services 140
Additional Systems 141
Staffing Issues 142
Likely Change Issues 142
Contents ix
Vision of the Future 142
Summary 143
12 Getting Started with Service-Oriented Architectures 145
Establish a Service-Oriented Architecture 146
Design Considerations 146
Staffing Issues 148
Likely Change Issues 149
What If Things Are Not Going as Planned? 150
The Data Warehouse Was Growing Much Faster than Expected 150
The Response Time of the Services Provided by an Internal
System Was Inadequate 151
Putting It All Together 157
Services and Service-Oriented Architectures 157
SOA Governance 161
Summary 162
13 Getting Started with Cloud Computing 163
Expand your Internal SOA to Include External Services 164
Staffing Issues 164
Likely Change Issues 164
Governance Considerations 165
Legal Issues 165
Business Issues 165
Technical Issues 165
Data Center Considerations 166
Availability Issues 166
Disaster Recovery Issues 167
Examples of Technical Issues Related to Availability 167
Failover Options for Messaging and Databases 167
Database Availability Options 168
Replication Options for Messaging and Databases 169
Cloud Brokers 170
Should You Be Your Own Cloud Provider? 170
Summary 170
14 Revisiting the Business Trip in the Not-Too-Distant
Future 171
Services for C. R.’s Business Trip 171
The Future for C. R.’s Organization 174
Summary 175