Virtualization: the shadow of the Cloud

In recent years, we have heard a new term called Cloud, which means in general lines to have the service or application available on the internet reachable from anywhere, quite different from the traditional model where the application runs in a specific server and reachable only from a closed network. The Cloud comes with a different concept of work, instead of you buy the hardware, take care of the maintenance and provide all infrastructure, you just buy a piece of service where you will put your application to run – the simplest and practical example we see it is the email, instead of having the server mail to host you domain and provide the service, there are many companies providing this service where you pay a monthly or yearly subscription and access from anywhere and just forget the maintenance worries.

Although, do you know how the Cloud service usually works behind the scenes? It’s a complex environment and varies a lot from service to service, but the main though is to have a hardware that can work to run as many “clients” as possible in order to use the full capacity of the hardware, and make this model profitable. The service can vary widely because in our giving example about Email service, possibly the server would run only one email service and then shared with many customers. The complex service would have from each customer some specific features which would be pretty hard to match with another customer and share the same resource. In order to solve this gap, it would have another layer which splits the server in many other small servers, known as Virtualization.

To give a better idea how virtualization works, imagine the company has a very powerful server with lots of processors, memory and disk space, each time a customer comes with a specific requirement, the administrator will slice the server and create a “virtual server” or “virtual machine” with the resources to meet the requirement. This is the mentioned added layer that will be used for the customer with specific purposes and totally isolated from the rest of the resources of the powerful server.

You might be wondering that only companies with specific requirement can afford this kind of hardware!! Actually at home you can also have a virtualization environment with no money involved (or a little), of course not powerful as a server, but the same hardware using different purposes.

Let’s describe some possible scenarios:

- You might have special needs for specific software that you use only works in a specific operating system, but you don’t want to downgrade the whole environment, thus with virtualization you would keep your current operating system and create a virtual machine (VM) and install the operating system required for that. Eg: your laptop running MS Windows 7, but you use a program that works only on MS Windows XP, so this XP version would be a VM.

- A very interesting requirement - You just bought a Mac and of course some programs are incompatible with OSX and only run on Windows. Not problem, you will install this program into a VM by creating a VM to install your MS Windows 7 and later your program, so that it will be easy to switch platforms in clicks and taking advantage of both platforms.

- You would like to install a trial program and test if it fits on what you are looking for, but don’t want to do this on your fresh and clean operating system recently installed, so you would create a new VM, install the operating system, install the trial software, test and decide if it’s worth to have on your “real” computer. This is much easier to do because if you don’t like, you can reverse back a copy of this VM or just leave this VM for testing purposes.

Did you enjoy this idea? So take a look at those vendors’s website and look for the products, some are free, others paid – just be aware of the minimum requirement to run the software virtualization on your PC or laptop:




- VMWare Player from VMWare (Windows and Linux) - www.vmware.com
- VMWare Fusion from VMWare (Mac only) - www.vmware.com
- Virtual Box from Oracle (Windows, Linux and Mac) - www.virtualbox.org
- Parallels Desktop from Parallels (Mac only) - www.parallels.com