1. BY AARON WEISS
COMPUTING IN
THE CLOUDS
Powerful services and applications are being
integrated and packaged on the Web in what the
industry now calls “cloud computing”
Quick, go outside and look up at the clouds in the sky. What
shapes do you see? A ball of cotton? A bunny rabbit? A
massively parallel distributed data center? If the latter sounds
spot on, you might already be computing in the clouds.
At least, that’s the latest catchphrase buzzing around the
industry. “Cloud computing,” as it’s being called by everyone
from IBM to Google to Amazon to Microsoft, is supposedly
the next big thing. But like the clouds themselves, “cloud
computing” can take on different shapes depending on the
viewer, and often seems a little fuzzy at the edges.
Illustration by James O’Brien
16 COMPUTING IN THE CLOUDS DECEMBER 2007

2. COMPUTING IN THE CLOUDS DECEMBER 2005 17

3. To some, the cloud looks like Web- tion, of course. Desktop (and laptop)
based applications, a revival of the computing power has been on an
thin-client. To others, the cloud looks accelerated tear for 30 years. But the
like utility computing, a grid that networked era, and the data centers
charges metered rates for processing that power it, are starting to make
time. Then again, the cloud could be the IT industry—and its investors—
distributed or parallel computing, take a fresh look at Watson’s per-
designed to scale complex processes spective on centralized computing, if
for improved efficiency. Maybe every- not his specific enumeration.
Both Google and IBM have a vested interest in encouraging
cloud computing: THEY NEED PEOPLE TO HIRE.
one is right. There are many shapes But data centers aren’t new, either.
in the clouds. In the dot-com boom of the mid-
’90s, many a startup invested venture
Cloud Shapes: The Data Center capital into traditional enterprise
It is not news that today’s major solutions like Sun SPARC servers. Is
Internet companies have built massive this the cloud?
data centers to power their online Yes and no. Google is often credit-
businesses. Decades ago, computing ed with innovating search on the
power was concentrated in main- Web and, more recently, advertising.
frames tucked away behind the scenes But to many, Google’s architecture
because there was no alternative— behind the scenes has spawned just
only a hulking room-sized box that as significant a revolution.
could contain any significant amount The data centers of the early dot-
of computational power. The idea com era were, in some respects,
that this power could be distributed direct descendents of Watson’s main-
rather than centralized seemed like frames. Physically smaller, perhaps,
such folly that in 1943, IBM but Sun servers and their ilk contin-
Chairman Thomas Watson said ued to represent an exclusive kind of
famously (or infamously) that “I computing—concentrated power
think there’s a world market for designed, and priced, for exclusive
maybe five computers.” customers—namely, enterprise.
The era of the personal computer But Google turned the data
that has flourished since the 1970s center model on its head. Rather
directly contradicted Watson’s predic- than power a network with a
18 COMPUTING IN THE CLOUDS DECEMBER 2007

4. small number of high-powered ter at a derelict factory site on the
and very expensive servers, why banks of the Columbia River in the
not deploy cheap, commodity Pacific Northwest, located both near
hardware in large numbers? cheap hydroelectric energy and a
Today, Google runs an estimated major trans-Pacific Internet node.
half-million servers clustered into a Likewise, Microsoft, IBM, and others
dozen or so physical locations. By are following suit, scouting sites both in
creating a network that is spread thin the Pacific Northwest and Canada where
and wide rather than narrow and hydroelectric power is cheaper (and green-
deep, Google created a new kind of er) than the coal-derived power used
concentrated power—derived more throughout much of the U.S. The eyes of
from scale of the whole than any one investors are also turning toward China,
constituent part. This, some say, where new power plants are being rapidly
describes the cloud. built (and, some are quick to caution,
As computational and networking without the “costly” burdens of environ-
architecture, the cloud is very robust. mental controls).
Sometimes described as “self-heal-
B
ing,” a thin, wide network can recov- esides cheaper power,
er gracefully from the most common data centers are making
ailments, such as connection and heavy use of virtualiza-
hardware failures, because there are tion to squeeze the most
so many more drones available to out of the watts they’re
take on the work. consuming. With major
But a cloud can consume a lot of vendors like VMWare
power to run. Aside from the power and Citrix, which recently acquired
needed to drive thousands, or hun- the Xen virtualization platform,
dreds of thousands, of processors increasingly targeting the data center,
and peripherals—hard drives, cooling virtualization allows a single server
fans—all these whirring machines to run multiple operating instances
generate lots of heat. It is estimated simultaneously. By sandboxing each
that 50 percent of energy costs in OS inside artificial boundaries, not
running a large data center are only can each instance run indepen-
derived from cooling needs alone. dently of the others, but CPU idle
Worse still for the cloud, the world time is minimized.
is immersed in a global energy Just what distinguishes a “cloud”
crunch, as both demand and specula- from “a bunch of machines” can be a
tion has driven up pricing for most little fuzzy. But the next evolution
conventional energies toward record that may illuminate the fog is the so-
levels. called “data center OS”—or, in the
Reducing the operating costs of a spirit of the buzz, the CloudOS. In
Google-inspired data center cloud the fall of this year, VMWare and
involves both physical and virtual Cisco announced a joint venture to
solutions. Physically, data centers are develop such a “fabric” (to use their
like plants arcing toward the sun- word in spite of the mixed
light, migrating toward cheap energy. metaphor).
Google is building a major data cen- In a data center like that employed
COMPUTING IN THE CLOUDS DECEMBER 2007 19

5. by Google and the many other enter- into sub-tasks. Those sub-tasks can
prises inspired by their model, each be broken into even smaller tasks,
server is fundamentally an indepen- and so on, until you’re nearly down
dent machine running its own copy to “bare metal” as they say and deal-
of an operating system. For servers to ing with disk and memory access.
work together on common tasks
I
requires an abstraction layer of soft- deally, if tasks are broken into
ware—often, highly specialized, cus- their smallest constituent jobs,
tom software—that intelligently and each job could be complet-
divvies up jobs. But a more efficient ed simultaneously using avail-
and resource-friendly solution would able processing resources
be a single operating system, which somewhere in the cloud, you
intrinsically utilizes the resources of could achieve an optimally effi-
many machines. cient architecture: the most optimistic
Essentially, an operating system is definition of distributed computing.
designed to manage resources—hard In reality, some jobs are dependent
drive space, memory, and so on. A on the results of other jobs.
true data center, or cloud, OS will Furthermore, designing algorithms to
treat every processing unit available most effectively divide jobs and dis-
as just another resource, relying on tribute them throughout the cloud in
networking channels to replicate the real time is complex, to understate
kinds of intra-server channels that the case.
now coordinate events within a single But distributed computing, like the
physical machine. Under the com- data center itself, is not inherently
mand of a single “omniscient” oper- new to the era of the cloud. If we
ating system, the cloud becomes a consider the entire Internet a cloud,
more cohesive entity. one need only look at popular pro-
jects like SETI@home and
Cloud Shapes: Distributed Computing Folding@home to see public exam-
Whether “the cloud” represents a ples of distributed computing at
data center at a single physical loca- work. In these projects, individuals
tion or dozens, hundreds, or thou- run software on their PC which con-
sands of data centers spread around nects them to a server that divides
the world, its speed and efficiency is large jobs among small clients to
limited by how intelligently it dele- crunch numbers toward a particular
gates responsibility. goal—in these examples, searching
Completing any general computing for alien life among radio waves and
task—say, retrieving the results of a computing protein folding simula-
search with relevant contextual tions to aid medical research. You
advertisements—requires a long could even consider botnets—soft-
series of smaller jobs to be complet- ware that maliciously infects unwit-
ed. Database queries, parsing of ting client machines to send out
results, construction of result sets, parcels of spam—a form of nefarious
and formatting of result pages, to distributed computing.
name the most common. Even these The open source project Hadoop
tasks can be further broken down provides a general-purpose frame-
20 COMPUTING IN THE CLOUDS DECEMBER 2007

6. work for developers to rapidly would submit jobs to these number-
employ distributed computing in a crunching powerhouses (in their
wide variety of projects. Actively day), and be billed for the cost of
under development within the aus- cycles used. Processing time was
pices of the Apache Foundation, delivered like electricity—you paid
Hadoop liberates software developers for what you used.
from creating specialized custom Today, most medium to large-sized
software for taking advantage of dis- organizations invest in their own
tributed computing in a cloud. data centers and use them at will.
Capable of distributing petabytes of Although processing cycles are not
data-processing across thousands of metered like a utility, there are signif-
computing nodes, the Hadoop plat- icant costs to building a data cen-
form is itself comprised of several ter—real estate, hardware, power,
WHY NOT JUST MOVE ALL PROCESSING
POWER TO THE CLOUD, and walk around with an
ultralight imput device with a screen?
technologies to ensure efficiency and cooling, and ongoing maintenance.
data integrity as data swirls around What’s worse for the balance sheet
the cloud. Some of these sub- is that organizations need to plan for
projects, like MapReduce which worst-case scenarios. In the case of a
divides jobs into component tasks, data center, not only can this include
and HDFS, the Hadoop Distributed the costs of backup and redundancy,
Filesystem, can be employed individ- but in overpowered servers capable
ually or together by developers in of handling loads which can peak
their applications. high but occur infrequently. Bus-
inesses may find themselves using 99
Cloud Shapes: A Utility Grid percent of their computing capacity
It seems like every shape one sees in only 10 percent of the time, leaving
the cloud is inspired by a computing expensive equipment often idle and
model from the past. Back in the angering the accountants.
days of mainframes and fancy super- In the Web space there is a thriv-
computers housed at research univer- ing market of hosting providers who
sities, valuable processing time was invest in their own data centers and
essentially for sale. Researchers sell usage to customers, be they indi-
COMPUTING IN THE CLOUDS DECEMBER 2007 21

7. viduals or businesses. Although host- machine in Amazon’s cloud. Using
ing providers can go some way virtualization, Amazon presents the
toward minimizing underutilization machine image to the end user as if it
of in-house servers by attaching sur- were a dedicated server, with the
charges to peak usage, their capacity same degree of access an administra-
to stretch can be limited. Providers tor would have to their own server.
typically assign clients to a whole or Customers can choose configura-
partial physical server, and do not tion templates for their machine
truly replicate the kinds of cloud fea- instance—for example, a server with
tures, like distributed computing, 1.7GB of memory, one processing
Software, in a cloud, becomes a service. To a company like
Microsoft, whose substantial fortunes are built on software
as a purchasable, local application, THE THREAT IS
NOT FALLING ON DEAF EARS.
that a dedicated data center can offer. core, and 160GB of storage space.
Meanwhile, massive companies Additional configurations support
like Amazon, Google, and IBM have more memory, more cores, and more
invested in, innovated, and become storage. But the real magic in EC2 is
expert at housing their own large- that customers can create and destroy
scale data centers. Invoking the idea machine instances at will. As a result,
of the cloud, all three also sense software can scale itself to exactly
opportunity: Why not scale up their the amount of computing power it
data centers—grow the cloud—and requires.
create business models to support Consider a Web-based application
third-party use? running in Amazon’s cloud. Suppose
In fact, Internet retail giant there is a sudden surge in visitors,
Amazon is the first out of the gate to perhaps thanks to media coverage.
commercialize their cloud. After a Today, many Web applications fail
period of limited access testing, under the load of big traffic spikes.
Amazon opened their Elastic But in the cloud, assuming that the
Compute Cloud, or EC2, to fee- Web application has been designed
based public use in October 2007. intelligently, additional machine
To use Amazon’s EC2, customers instances can be launched on
first create a virtual image of their demand. The application dynamically,
complete software environment using and gracefully, scales up. When traffic
provided tools. The image is then slows down, the app can scale down,
used to create an “instance” of a terminating the extra instances.
22 COMPUTING IN THE CLOUDS DECEMBER 2007

8. Amazon then charges customers these kinds of massive, sandboxed
based on their cumulative “instance data centers dedicated for student
hours,” a way of metering usage, use, and many lack instructors with
currently set at $0.10 per instance leading-edge experience.
hour for the most basic instance type. To some industry analysts, com-
To provide consistent and predictable modified cloud computing like
performance, machine instance types Amazon’s EC2 will change the face
are rated by what Amazon calls of enterprise computing. It may pave
“compute units,” which deliver a the way to where businesses no
specific, known amount of perfor- longer invest anything into data cen-
mance, regardless of the underlying ters of their own. Out goes the hard-
hardware Amazon is using inside ware, out goes the power bill, and
their cloud. A second charge applies out goes all the processing power
to data moved in and out of that rarely gets used. Instead, they
Amazon’s network, ranging from buy cloud computing time from com-
$0.10 to $0.18 per gigabyte. mercial providers, who can specialize
In contrast to Amazon’s commer- in building massive data centers at
cial effort, Google and IBM recently sites selected to minimize operating
announced a partnership to apply a costs.
similar utility cloud model to com-
puter science education. The two Cloud Shapes: Software as a Service
companies have put together a dedi- As radical a shift as cloud computing
cated data center mixing both com- may represent for the enterprise—
modity and enterprise hardware. who needs servers?—some think it
Running open source software will radically change personal com-
including Linux, Xen virtualization, puting even more. Who needs com-
and Apache Hadoop, the puters at all? At least, the kind that
Google/IBM cloud presents a distrib- eat up battery life and contain churn-
uted computing canvas for educa- ing hard drives. Why not just move
tional access. Both Google and IBM all processing power to the cloud,
have a vested interest in encouraging and walk around with an ultralight
cloud computing: They need people input device with a screen?
to hire. Some say it’s already begun.
Burgeoning Web applications have
A
considerable concern been the rage for several years.
among major enterprise Fueled by technological evolutions
is that today’s computer like AJAX, which allows browser-
science students lack based code to behave more like a
access to the distributed local application, and people’s desire
computing environ- for mobility and data ubiquity, we
ments that make up the increasingly use the Web for applica-
cloud. Companies like Google will tion functionality. E-mail was both
need new hires experienced in writing the first “killer app” for the Internet,
code designed to run in a cloud of and later, on the Web. For many
perhaps thousands of processors. But today, Web-based e-mail is the only
educational institutions don’t have kind they use.
COMPUTING IN THE CLOUDS DECEMBER 2007 23

9. Taken further, Web-based applica- ruptive force and a whole new way.
tions like Google Docs threaten core Carr predicts that Google and Apple
productivity applications on the will partner to push the cloud com-
desktop. While the features of puting/software-as-a-service model
Google Docs are a slim shadow of a even further. He foresees a lightweight
major, and majorly profitable, appli- mobile device crafted by Apple that
cation like Microsoft Word, it pro- will tap into Google’s cloud, bringing
vides a taste of a cloud-based future. together the two masters of the front
Your data is reachable anywhere, and end and the back end.
the only software you need to access In the near-term, a ubiquitous
it is a browser. Which, in turn, means cloud faces obstacles. Critics argue
THE CLOUD DEMANDS A HIGH DEGREE OF
TRUST. Significant amounts of data which were previously
stored only in individual offices and homes would now reside
in data centers controlled by third-parties.
that your data and your applications that visions like Carr’s are simply
are available in one form another revivals of failed thin-client dreams
from your desktop PC, your laptop, of the past. Thin clients like those
and your handheld. touted by Oracle-founder Larry
Software, in the cloud, becomes a Ellison in the ’90s have not managed
service. To a company like Microsoft, to become cost-effective. With prices
whose substantial fortunes are built plummeting and performance sky-
on software as a purchasable, local rocketing for full-featured desktop
application, the threat is not falling and laptop computers, it has been
on deaf ears. Windows Live, difficult to produce a relatively pow-
Microsoft’s “cloud,” may be today’s erless thin client at a low enough cost
take on Windows 1.0—a look into to attract buyers.
the future. Advocates for thin client cloud
Even Adobe has begun to launch computing argue that full-fledged
stripped-down versions of its compu- machines, however powerful, are also
tationally-heavy marquee titles as a hassle with negative productivity.
Web-based services, including They have many parts that can fail
Photoshop and the video editing suite and their software needs constant
Premiere. care and feeding in a world riddled
Pundits and futurists like Nicholas with software updates, viruses, and
Carr love this stuff because the cloud spyware. Centralizing processing
represents a paradigm shift and a dis- power in the cloud liberates users to
24 COMPUTING IN THE CLOUDS DECEMBER 2007

10. choose efficient, uncomplicated access Software as a service in the cloud
machines. This argument, and its can revive fears of vendor lock-in, a
potential economic feasibility, gains significant consideration in the main-
weight in today’s environment, where frame era. Supposing a cloud opera-
laptop sales are outpacing the desk- tor and a thin-client vendor partner
top, and even more mobile devices together, it is possible that each half
are becoming commonplace. will require the other. Services from
the cloud may be inaccessible to
F
or cloud computing to those without an access device from a
move front and center, the single brand. Some fear that the
networks that tie every- cloud could encourage the growth of
thing together need to be walled-gardens, a potential step back
extremely robust. After compared to the relatively open
all, the cloud represents a Internet of today.
significant inversion from
personal computing in the 1970s and Partly Cloudy?
1980s, when machines stood alone There are those who scoff that
and derived all of their utility from “cloud computing” is just the latest
their own capabilities. Under the branding of some old, familiar com-
cloud, client machines become nearly puting models—which is partly true.
useless on their own. Are our net- It’s a buzzword almost designed to be
works ready to handle the load? vague, but cloud computing is more
Many would say no, especially than just a lot of fog.
those living in the large U.S. market, The cloud concept draws on many
where broadband quality and pene- existing technologies and architec-
tration fares poorly relative to many tures. Centralizing computing power
smaller industrialized nations. In con- is not new and, if anything, is a
trast to local computing power, which return to the computer’s roots. Nor is
continues to boom year after year, utility computing new, or distributed
broadband advances here have been computing, or even software as a
slow and may create at least a short- service.
term bottleneck holding back a major But the cloud is new in that it inte-
shift toward mainstream cloud com- grates all of the above computing
puting. models. This integration requires
Network bandwidth aside, the computing’s center of power to shift
cloud raises concerns among privacy from the processing unit to the net- PERMISSION TO MAKE DIGITAL OR HARD
advocates. Most significantly, the work. Inside the cloud, processors COPIES OF ALL OR PART OF THIS WORK FOR
PERSONAL OR CLASSROOM USE IS GRANT-
cloud demands a high degree of trust. become commodities. It is the net- ED WITHOUT FEE PROVIDED THAT COPIES
Significant amounts of data which work that holds the cloud together, ARE NOT MADE OR DISTRIBUTED FOR PROFIT
were previously stored only in indi-
~
and connects the clouds to each other OR COMMERCIAL ADVANTAGE AND THAT
COPIES BEAR THIS NOTICE AND THE FULL
vidual offices and homes would now and the sky to the ground. CITATION ON THE FIRST PAGE. TO COPY
reside in data centers controlled by OTHERWISE, TO REPUBLISH, TO POST ON
third-parties. Do we have adequate SERVERS OR TO REDISTRIBUTE TO LISTS,
Aaron Weiss is a technology writer and REQUIRES PRIOR SPECIFIC PERMISSION
privacy laws? How should encryption Web developer shivering in upstate New York, as AND/OR A FEE.
play a role? well as human proprieter of livenudecats.com © ACM 1091-556/07/01200 $5.00
COMPUTING IN THE CLOUDS DECEMBER 2007 25