The Fundamental Concept of Virtualization

Since virtualization is at the forefront of technologicalapproximately doubling every 18 months. Just think
advances and because every mover and shaker inhow many times it has doubled in the last 20 years:
the industry (IBM, Microsoft, Dell, etc. plus industrystart with 100 million instructions per second (MIPS)
analysts) have solidly endorsed it, you should haveand you'll see that in the second 18-month period it
some fundamental concept of what this is all about.would reach 200, in the third 18-month period, 400, in
It is the future of computing coming right at you.the fourth 18-month period, 800, etc. This gets to be
So here goes.very stratospheric very quickly.
Let's start by talking about something that I'm sureHow many MIPS are you currently using? Fact: Your
everyone is familiar with - remote control devices. Ifhardware is underutilized.
you are like me, you have some kind ofNow, let's move from your home workstation and
entertainment center. Mine consists of a television, alook at the scene in a business of 20 workstations all
cable box, a receiver, a DVD player, a Blu-ray player,connected to servers and shared printers. Like your
a DVD recorder, and a CD player. That adds up to 7home workstation, each workstation in the business
pieces of equipment. Each piece of equipment arrivedhas its own computer tower, monitor and mouse.
with its own remote control device. This means thatEach of these arrangements consumes a certain
I have 7 remote control devices lying on my coffeeamount of electricity and that very definitely has an
table, usually in some state of disarray.impact on the electric bill that arrives each month.
Each remote control device is set to the sameAdd to these 20 workstations, three servers: (1) a
frequency as the machine it controls. Each device andmail server, (2) an applications server, and (3) a file
its corresponding machine speak the same language.server. Each server runs on one OS and provides
And that is why my television remote has no effectservices to the workstations. And add further a
on my Blu-ray player or CD player or cable box.security appliance, a network switch, a router, and a
Each remote control device and correspondingNAS (network-attached storage) for back-ups for
machine is a piece of hardware. What makes themthe ever-increasing volume of data off the servers
work are programmed instructions - software.and workstations.
So someone came along and figured out how toAt 50 workstations you might add another 2-3
simplify all this. A universal remote was created thatservers. At 100 workstations you might add another
can duplicate or replicate the frequency and language3 on top of the 2-3 you added at 50. Further, as the
used in each of your remote control devices so thatcompany's IT infrastructure expands (as the
one remote control device is all that is needed tocompany grows), it becomes necessary at a certain
make all your machines work. In other words, withinpoint to hire an IT person and then another and
that one universal device is a virtual television remoteanother, etc. So you see the IT overhead increasing
control device, a virtual cable box remote controlin terms of (a) buying more hardware and software,
device, a virtual receiver remote control device, a(b) adding IT personnel, and (c) higher energy
virtual DVD remote control device, a virtual Blu-rayconsumption. And the hardware underutilization also
remote control device, a virtual DVD recordergrows.
remote control device, and a virtual CD playerIn a tiny company where the IT infrastructure is
remote control device.static (unchanging), virtualization would not be
What are the advantages of this? Well, the first andneeded. But a company is not a static entity. It
most obvious advantage is that I can now take allgrows or it shrinks and efforts to keep it static
those remotes that have been occupying coffeeusually bring about some degree of contraction. So
table real estate and put them in a drawereven if you currently don't need to use this tool, it's
somewhere. I only need the universal remote.important to have a fundamental understanding of it
Another advantage is that I now don't have to keepfor the day when you might need to employ it.
a case of batteries in the closet to power all thoseHere's how virtualization works:
devices. That saves me some money as I only haveRemember the example of the 7 remote control
to power the universal device. Eventually the amountdevices being virtualized into the one universal
of money saved will pay for what I spent on thecontroller? Well, virtualization technology is comprised
universal device.of specially written software code that does the
In general, virtual means the quality of affectingsame thing for servers, desktop computers,
something without actually being that something. Itapplications, storage devices and other appliances. I
has come to mean, in modern times, "being indon't want to get into the technical details of how
essence or effect but not in fact." In the abovethis is done because this article is just about the
example, each of the remote control devicesfundamental concept of virtualization. Suffice it to
appeared to be in the universal controller withoutsay, 7 physical servers could be consolidated
actually physically being there. Thus, they were(virtualized) into ONE physical server (one HOST
virtualized. They were there in essence but not inserver instead of 7). In the same way applications
fact and each virtual device could create the samecan be migrated from their normal residence - a
effect as the real device.desktop - to a virtualized environment on the virtual
Okay. That is a bedrock concept of what it meansserver. This means that eventually the desktop can
to virtualize something. Now let's move it over to thebe replaced with what is called a "thin client." A thin
field of computers and networks.client (sometimes also called a lean or slim client) is a
Virtualization and Computersdevice that can be attached to the back of a
As a home user, you have a single workstation that,monitor and which communicates with the virtual
aside from your desk, chair and surrounding workserver to open whatever application has been
space, consists of hardware (a tower containing aselected by the user. The thin client fulfills the
motherboard, a CPU, one or more hard drives, RAM,traditional role of the desktop. Thin clients are usually
a power supply, cooling system, etc.; a monitor; amuch less expensive than a desktop computer.
mouse; CD/DVD player; and usually a dedicatedFurther, appliances like network-attached storages,
printer) plus software (the programming code orsecurity appliances, and a very large host of other
instructions that have been installed on the hardappliances can be virtualized onto a server. I'm hoping
drive). All this is made to work by ONE operatingthat you are starting to get the idea.
system or OS (Windows XP, Vista, Windows 7,The physical mail server, applications server and file
Linux, etc.). The OS runs the computer and providesserver have been consolidated (virtualized) into one
you with an interface with which to issue commandsphysical machine - the virtual server. The processing
to the computer system. Computer technology, aspower of the virtual server will be more efficiently
we have known it, required one OS per computer.harnessed. The workstations have been retired and
And, depending on the equipment you use with thisreplaced with thin clients and there's a lot less iron in
workstation, it uses a certain volume of electricity.this company. There's also less energy consumption.
One thing is certain, no matter what you use yourAnd there can now be a better utilization of IT
home computer for, you are only tapping into a verypersonnel who can now focus more time and
small fraction of what your CPU is capable ofattention to the core business processes of the
(presuming of course that your CPU isn't someenterprise.
ancient dinosaur). Processing power has been