,of Contents
Cover image
Front Matter
Copyright
Dedication
About the Authors
About the Technical Editor
Contributors
Foreword
Preface
Chapter 1. Introduction
Chapter 2. Infrastructure as a Service
Chapter 3. Platform as a Service
Chapter 4. Software as a Service
Chapter 5. Paradigms for Developing Cloud Applications
Chapter 6. Addressing the Cloud Challenges
Chapter 7. Designing Cloud Security
Chapter 8. Managing the Cloud
Chapter 9. Related Technologies
Chapter 10. Future Trends and Research Directions
Chapter 1. Introduction
Information in This Chapter
•Where Are We Today?
•The Future Evolution
•What Is Cloud Computing?
•Cloud Deployment Models
•Business Drivers for Cloud Computing
•Introduction to Cloud Technologies
Cloud computing is one of the major transformations that is taking place in the computer industry, and that, in turn, is transforming society. This
chapter provides an overview of the key concepts of cloud computing, analyzes how cloud computing is different from traditional computing and
how it enables new applications while providing highly scalable versions of traditional applications. It also describes the forces driving cloud
computing, describes a well-known taxonomy of cloud architectures, and discusses at a high level the technological challenges inherent in cloud
computing.
Keywords
IaaS, PaaS, SaaS, public cloud, private cloud, scalability, multi-tenancy, availability
Introduction
,Cloud Computing is one of the major technologies predicted to revolutionize the future
of computing. The model of delivering IT as a service has several advantages. It enables
current businesses to dynamically adapt their computing infrastructure to meet the
rapidly changing requirements of the environment. Perhaps more importantly, it greatly
reduces the complexities of IT management, enabling more pervasive use of IT. Further,
it is an attractive option for small and medium enterprises to reduce upfront investments,
enabling them to use sophisticated business intelligence applications that only large
enterprises could previously afford. Cloud-hosted services also offer interesting reuse
opportunities and design challenges for application developers and platform providers.
Cloud computing has, therefore, created considerable excitement among technologists
in general.
This chapter provides a general overview of Cloud Computing, and the technological
and business factors that have given rise to its evolution. It takes a bird's-eye view of
the sweeping changes that cloud computing is bringing about. Is cloud computing
merely a cost-saving measure for enterprise IT? Are sites like Facebook the tip of the
iceberg in terms of a fundamental change in the way of doing business? If so, does
enterprise IT have to respond to this change, or take the risk of being left behind? By
surveying the cloud computing landscape at a high level, it will be easy to see how the
various components of cloud technology fit together. It will also be possible to put the
technology in the context of the business drivers of cloud computing.
Where are We Today?
Computing today is poised at a major point of inflection, similar to those in earlier
technological revolutions. A classic example of an earlier inflection is the anecdote that
is described in The Big Switch: Rewiring the World, from Edison to Google[1]. In a
small town in New York called Troy, an entrepreneur named Henry Burden set up a
factory to manufacture horseshoes. Troy was strategically located at the junction of the
Hudson River and the Erie Canal. Due to its location, horseshoes manufactured at Troy
could be shipped all over the United States. By making horseshoes in a factory near
water, Mr. Burden was able to transform an industry that was dominated by local
craftsmen across the US. However, the key technology that allowed him to carry out
this transformation had nothing to do with horses. It was the waterwheel he built in
order to generate electricity. Sixty feet tall, and weighing 250 tons, it generated the
electricity needed to power his horseshoe factory.
Burden stood at the mid-point of a transformation that has been called the Second
Industrial Revolution, made possible by the invention of electric power. The origins of
this revolution can be traced to the invention of the first battery by the Italian physicist
Alessandro Volta in 1800 at the University of Pavia. The revolution continued through
1882 with the operation of the first steam-powered electric power station at Holborn
Viaduct in London and eventually to the first half of the twentieth century, when
, electricity became ubiquitous and available through a socket in the wall. Henry Burden
was one of the many figures who drove this transformation by his usage of electric
power, creating demand for electricity that eventually led to electricity being
transformed from an obscure scientific curiosity to something that is omnipresent and
taken for granted in modern life. Perhaps Mr. Burden could not have grasped the
magnitude of changes that plentiful electric power would bring about.
By analogy, we may be poised at the midpoint of another transformation – now around
computing power – at the point where computing power has freed itself from the
confines of industrial enterprises and research institutions, but just before cheap and
massive computing resources are ubiquitous. In order to grasp the opportunities offered
by cloud computing, it is important to ask which direction are we moving in, and what
a future in which massive computing resources are as freely available as electricity may
look like.
AWAKE! for Morning in the Bowl of Night
Has flung the Stone that puts the Stars to Flight:
…
The Bird of Time has but a little way
To fly – and Lo! the Bird is on the Wing.
The Rubaiyat of Omar Khayyam, Translated into English in 1859, by Edward
FitzGerald
Evolution of the Web
To see the evolution of computing in the future, it is useful to look at the history. The
first wave of Internet-based computing, sometimes called Web 1.0, arrived in the 1990s.
In the typical interaction between a user and a web site, the web site would display some
information, and the user could click on the hyperlinks to get additional information.
Information flow was thus strictly one-way, from institutions that maintained web sites
to users. Therefore, the model of Web 1.0 was that of a gigantic library, with Google
and other search engines being the library catalog. However, even with this modest
change, enterprises (and enterprise IT) had to respond by putting up their own web sites
and publishing content that projected the image of the enterprise effectively on the Web
(Figure 1.1). Not doing so would have been analogous to not advertising when
competitors were advertising heavily.
Cover image
Front Matter
Copyright
Dedication
About the Authors
About the Technical Editor
Contributors
Foreword
Preface
Chapter 1. Introduction
Chapter 2. Infrastructure as a Service
Chapter 3. Platform as a Service
Chapter 4. Software as a Service
Chapter 5. Paradigms for Developing Cloud Applications
Chapter 6. Addressing the Cloud Challenges
Chapter 7. Designing Cloud Security
Chapter 8. Managing the Cloud
Chapter 9. Related Technologies
Chapter 10. Future Trends and Research Directions
Chapter 1. Introduction
Information in This Chapter
•Where Are We Today?
•The Future Evolution
•What Is Cloud Computing?
•Cloud Deployment Models
•Business Drivers for Cloud Computing
•Introduction to Cloud Technologies
Cloud computing is one of the major transformations that is taking place in the computer industry, and that, in turn, is transforming society. This
chapter provides an overview of the key concepts of cloud computing, analyzes how cloud computing is different from traditional computing and
how it enables new applications while providing highly scalable versions of traditional applications. It also describes the forces driving cloud
computing, describes a well-known taxonomy of cloud architectures, and discusses at a high level the technological challenges inherent in cloud
computing.
Keywords
IaaS, PaaS, SaaS, public cloud, private cloud, scalability, multi-tenancy, availability
Introduction
,Cloud Computing is one of the major technologies predicted to revolutionize the future
of computing. The model of delivering IT as a service has several advantages. It enables
current businesses to dynamically adapt their computing infrastructure to meet the
rapidly changing requirements of the environment. Perhaps more importantly, it greatly
reduces the complexities of IT management, enabling more pervasive use of IT. Further,
it is an attractive option for small and medium enterprises to reduce upfront investments,
enabling them to use sophisticated business intelligence applications that only large
enterprises could previously afford. Cloud-hosted services also offer interesting reuse
opportunities and design challenges for application developers and platform providers.
Cloud computing has, therefore, created considerable excitement among technologists
in general.
This chapter provides a general overview of Cloud Computing, and the technological
and business factors that have given rise to its evolution. It takes a bird's-eye view of
the sweeping changes that cloud computing is bringing about. Is cloud computing
merely a cost-saving measure for enterprise IT? Are sites like Facebook the tip of the
iceberg in terms of a fundamental change in the way of doing business? If so, does
enterprise IT have to respond to this change, or take the risk of being left behind? By
surveying the cloud computing landscape at a high level, it will be easy to see how the
various components of cloud technology fit together. It will also be possible to put the
technology in the context of the business drivers of cloud computing.
Where are We Today?
Computing today is poised at a major point of inflection, similar to those in earlier
technological revolutions. A classic example of an earlier inflection is the anecdote that
is described in The Big Switch: Rewiring the World, from Edison to Google[1]. In a
small town in New York called Troy, an entrepreneur named Henry Burden set up a
factory to manufacture horseshoes. Troy was strategically located at the junction of the
Hudson River and the Erie Canal. Due to its location, horseshoes manufactured at Troy
could be shipped all over the United States. By making horseshoes in a factory near
water, Mr. Burden was able to transform an industry that was dominated by local
craftsmen across the US. However, the key technology that allowed him to carry out
this transformation had nothing to do with horses. It was the waterwheel he built in
order to generate electricity. Sixty feet tall, and weighing 250 tons, it generated the
electricity needed to power his horseshoe factory.
Burden stood at the mid-point of a transformation that has been called the Second
Industrial Revolution, made possible by the invention of electric power. The origins of
this revolution can be traced to the invention of the first battery by the Italian physicist
Alessandro Volta in 1800 at the University of Pavia. The revolution continued through
1882 with the operation of the first steam-powered electric power station at Holborn
Viaduct in London and eventually to the first half of the twentieth century, when
, electricity became ubiquitous and available through a socket in the wall. Henry Burden
was one of the many figures who drove this transformation by his usage of electric
power, creating demand for electricity that eventually led to electricity being
transformed from an obscure scientific curiosity to something that is omnipresent and
taken for granted in modern life. Perhaps Mr. Burden could not have grasped the
magnitude of changes that plentiful electric power would bring about.
By analogy, we may be poised at the midpoint of another transformation – now around
computing power – at the point where computing power has freed itself from the
confines of industrial enterprises and research institutions, but just before cheap and
massive computing resources are ubiquitous. In order to grasp the opportunities offered
by cloud computing, it is important to ask which direction are we moving in, and what
a future in which massive computing resources are as freely available as electricity may
look like.
AWAKE! for Morning in the Bowl of Night
Has flung the Stone that puts the Stars to Flight:
…
The Bird of Time has but a little way
To fly – and Lo! the Bird is on the Wing.
The Rubaiyat of Omar Khayyam, Translated into English in 1859, by Edward
FitzGerald
Evolution of the Web
To see the evolution of computing in the future, it is useful to look at the history. The
first wave of Internet-based computing, sometimes called Web 1.0, arrived in the 1990s.
In the typical interaction between a user and a web site, the web site would display some
information, and the user could click on the hyperlinks to get additional information.
Information flow was thus strictly one-way, from institutions that maintained web sites
to users. Therefore, the model of Web 1.0 was that of a gigantic library, with Google
and other search engines being the library catalog. However, even with this modest
change, enterprises (and enterprise IT) had to respond by putting up their own web sites
and publishing content that projected the image of the enterprise effectively on the Web
(Figure 1.1). Not doing so would have been analogous to not advertising when
competitors were advertising heavily.
