xxv
Introduction
The purpose of this book is to clear up some of the mystery surrounding the
topic of cloud computing. In order to understand how computing has
evolved, one must understand the evolution of computing from a historical
perspective, focusing primarily on those advances that led to the develop-
ment of cloud computing, such as the transition from mainframes to desk-
tops, laptops, mobile devices, and on to the cloud. We will also need to
discuss in some detail the key components that are critical to make the
cloud computing paradigm feasible with the technology available today. We
will cover some of the standards that are used or are proposed for use in the
cloud computing model, since standardization is crucial to achieving wide-
spread acceptance of cloud computing. We will also discuss the means used
to manage effectively the infrastructure for cloud computing. Significant
legal considerations in properly protecting user data and mitigating corpo-
rate liability will also be covered. Finally, we will discuss what some of the
more successful cloud vendors have done and how their achievements have
helped the cloud model evolve.
Over the last five decades, businesses that use computing resources have
learned to contend with a vast array of buzzwords. Much of this
geek-speak
or marketing vapor, over time, has been guilty of making promises that
often are never kept. Some promises, to be sure, have been delivered,
although others have drifted into oblivion. When it comes to offering tech-
nology in a
pay-as-you-use
services model, most information technology (IT)
professionals have heard it all—from allocated resource management to grid
computing, to on-demand computing and software-as-a-service (SaaS), to
utility computing. A new buzzword,
cloud computing,
is presently in vogue
in the marketplace, and it is generating all sorts of confusion about what it
actually represents.
Intro.fm Page xxv Friday, May 22, 2009 11:24 AM
xxvi Cloud Computing
What Is the Cloud?
The term
cloud
has been used historically as a metaphor for the Internet.
This usage was originally derived from its common depiction in network
diagrams as an outline of a cloud, used to represent the transport of data
across carrier backbones (which owned the cloud) to an endpoint location
on the other side of the cloud. This concept dates back as early as 1961,
when Professor John McCarthy suggested that computer time-sharing tech-
nology might lead to a future where computing power and even specific
applications might be sold through a utility-type business model.
1
This idea
became very popular in the late 1960s, but by the mid-1970s the idea faded
away when it became clear that the IT-related technologies of the day were
unable to sustain such a futuristic computing model. However, since the
turn of the millennium, the concept has been revitalized. It was during this
time of revitalization that the term
cloud
computing
began to emerge in tech-
nology circles.
The Emergence of Cloud Computing
Utility computing
can be defined as the provision of computational and stor-
age resources as a metered service, similar to those provided by a traditional
public utility company. This, of course, is not a new idea. This form of com-
puting is growing in popularity, however, as companies have begun to
extend the model to a cloud computing paradigm providing virtual servers
that IT departments and users can access on demand. Early enterprise
adopters used utility computing mainly for non-mission-critical needs, but
that is quickly changing as trust and reliability issues are resolved.
Some people think cloud computing is the next big thing in the world
of IT. Others believe it is just another variation of the utility computing
model that has been repackaged in this decade as something new and cool.
However, it is not just the buzzword “cloud computing” that is causing con-
fusion among the masses. Currently, with so few cloud computing vendors
actually practicing this form of technology and also almost every analyst
from every research organization in the country defining the term differ-
ently, the meaning of the term has become very nebulous. Even among
those who think they understand it, definitions vary, and most of those def-
initions are hazy at best. To clear the haze and make some sense of the new
1. http://computinginthecloud.wordpress.com/2008/09/25/utility-cloud-computingflashback-
to-1961-prof-john-mccarthy, retrieved 5 Jan 2009.
Intro.fm Page xxvi Friday, May 22, 2009 11:24 AM
The Global Nature of the Cloud xxvii
concept, this book will attempt to help you understand just what cloud
computing really means, how disruptive to your business it may become in
the future, and what its advantages and disadvantages are.
As we said previously, the term
the cloud
is often used as a metaphor for
the Internet and has become a familiar cliché. However, when “the cloud” is
combined with “computing,” it causes a lot of confusion. Market research
analysts and technology vendors alike tend to define cloud computing very
narrowly, as a new type of utility computing that basically uses virtual serv-
ers that have been made available to third parties via the Internet. Others
tend to define the term using a very broad, all-encompassing application of
the virtual computing platform. They contend that anything beyond the
firewall perimeter is in the cloud. A more tempered view of cloud comput-
ing considers it the delivery of computational resources from a location
other than the one from which you are computing.
The Global Nature of the Cloud
The cloud sees no borders and thus has made the world a much smaller
place. The Internet is global in scope but respects only established commu-
nication paths. People from everywhere now have access to other people
from anywhere else. Globalization of computing assets may be the biggest
contribution the cloud has made to date. For this reason, the cloud is the
subject of many complex geopolitical issues. Cloud vendors must satisfy
myriad regulatory concerns in order to deliver cloud services to a global
market. When the Internet was in its infancy, many people believed cyber-
space was a distinct environment that needed laws specific to itself. Univer-
sity computing centers and the ARPANET were, for a time, the
encapsulated environments where the Internet existed. It took a while to get
business to warm up to the idea.
Cloud computing is still in its infancy. There is a hodge-podge of pro-
viders, both large and small, delivering a wide variety of cloud-based ser-
vices. For example, there are full-blown applications, support services, mail-
filtering services, storage services, etc. IT practitioners have learned to con-
tend with some of the many cloud-based services out of necessity as business
needs dictated. However, cloud computing aggregators and integrators are
already emerging, offering packages of products and services as a single
entry point into the cloud.
The concept of cloud computing becomes much more understandable
when one begins to think about what modern IT environments always
Intro.fm Page xxvii Friday, May 22, 2009 11:24 AM
xxviii Cloud Computing
require—the means to increase capacity or add capabilities to their infra-
structure dynamically, without investing money in the purchase of new
infrastructure, all the while without needing to conduct training for new
personnel and without the need for licensing new software. Given a solution
to the aforementioned needs, cloud computing models that encompass a
subscription-based or pay-per-use paradigm provide a service that can be
used over the Internet and extends an IT shop’s existing capabilities. Many
users have found that this approach provides a return on investment that IT
managers are more than willing to accept.
Cloud-Based Service Offerings
Cloud computing may be viewed as a resource available as a service for vir-
tual data centers, but cloud computing and virtual data centers are not the
same. For example, consider Amazon’s S3 Storage Service. This is a data
storage service designed for use across the Internet (i.e., the cloud). It is
designed to make web-scale computing easier for developers. According to
Amazon:
Amazon S3 provides a simple web services interface that can be
used to store and retrieve any amount of data, at any time, from
anywhere on the web. It gives any developer access to the same
highly scalable, reliable, fast, inexpensive data storage infrastructure
that Amazon uses to run its own global network of web sites. The
service aims to maximize benefits of scale and to pass those benefits
on to developers.
2
Amazon.com has played a vital role in the development of cloud com-
puting. In modernizing its data centers after the dot-com bubble burst in
2001, it discovered that the new cloud architecture it had implemented
resulted in some very significant internal efficiency improvements. By pro-
viding access to its systems for third-party users on a utility computing
basis, via Amazon Web Services, introduced in 2002, a revolution of sorts
began. Amazon Web Services began implementing its model by renting
computing cycles as a service outside a given user’s domain, wherever on the
planet that domain might be located. This approach modernized a style of
computing whereby IT-related capabilities could be provided “as a service”
2. http://aws.amazon.com/s3, retrieved 5 Jan 2009.
Intro.fm Page xxviii Friday, May 22, 2009 11:24 AM
Cloud-Based Service Offerings xxix
to users. By allowing their users to access technology-enabled services “in
the cloud,” without any need for knowledge of, expertise with, or control
over how the technology infrastructure that supports those services worked,
Amazon shifted the approach to computing radically. This approach trans-
formed cloud computing into a paradigm whereby data is permanently
stored in remote servers accessible via the Internet and cached temporarily
on client devices that may include desktops, tablet computers, notebooks,
hand-held devices, mobile phones, etc., and is often called
Software as a Ser-
vice
(SaaS).
SaaS is a type of cloud computing that delivers applications through a
browser to thousands of customers using a multiuser architecture. The focus
for SaaS is on the end user as opposed to managed services (described
below). For the customer, there are no up-front investment costs in servers
or software licensing. For the service provider, with just one product to
maintain, costs are relatively low compared to the costs incurred with a con-
ventional hosting model. Salesforce.com
3
is by far the best-known example
of SaaS computing among enterprise applications. Salesforce.com was
founded in 1999 by former Oracle executive Marc Benioff, who pioneered
the concept of delivering enterprise applications via a simple web site. Now-
days, SaaS is also commonly used for enterprise resource planning and
human resource applications. Another example is Google Apps, which pro-
vides online access via a web browser to the most common office and busi-
ness applications used today, all the while keeping the software and user
data stored on Google servers. A decade ago, no one could have predicted
the sudden rise of SaaS applications such as these.
Managed service providers (MSPs) offer one of the oldest forms of cloud
computing. Basically, a managed service is an application that is accessible to
an organization’s IT infrastructure rather than to end users. Services include
virus scanning for email, antispam services such as Postini,
4
desktop manage-
ment services such as those offered by CenterBeam
5
or Everdream,
6
and
3. http://www.salesforce.com , retrieved 5 Jan 2009.
4. In September 2007, Google acquired Postini, recognized as a global leader in on-demand
communications security and compliance solutions. This is further evidence of the aggrega-
tion of cloud service providers.
5. CenterBeam delivers services over the Internet using a SaaS model.
6. In November 2007, Dell signed an agreement to acquire Everdream, a leading provider of
SaaS solutions for remote service management. The planned acquisition was a key compo-
nent in Dell’s strategy of enabling customers to simplify IT. Everdream’s capabilities com-
plement those provided by the recently acquired SilverBack Technologies, further enabling
end-to-end remote management of customers’ IT environments.
Intro.fm Page xxix Friday, May 22, 2009 11:24 AM
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