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Understanding Virtualization

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http://linux.bihlman.com – Understanding Virtualization By Bob Matharoo Emerging Technologies “Virtualization” Our world is changing at a very fast pace and the main reason behind it is vomputers. Since their invention, the technology behind them has been continuously improving and changing. Every year some new technology replaces the old one which is better and more advanced. Computers have transformed from a big machine (equal to the size of room) to small and compact like Pocket PCs. With the passage of time many new software and applications were also being developed to help increase their output. Today we see that in every field computers are becoming a big necessity and that is why there is a boom in the industry of technology. One of the hottest technology these days is Virtualization, which basically means creating virtual environment with the help of software to run different applications like operating systems, software but using the common hardware resource. It can also be defined as combining software and hardware to create a Virtual machine which makes the single system to act as group of systems. A few years ago when virtualization was not invented yet, we used to have different systems with different OS as they cannot be installed on same systems. However, this problem was solved as people started installing different OS on different hard disk partitions. So during the boot time there were options asking which OS to run. With this the person was able to run only one OS at a time. Then Virtualization was invented which allow user to run user more than one OS at a time. This was made possible through software generally called hypervisors. They allowed users to install a new OS just like a new program is installed. For example- A person can run Windows Server 2003 over Windows XP in a new window just like a program is running on XP, all this on a common system. The main requirement of virtualization is a powerful host computer because it has to share the system resources with the virtual machines. Therefore the computer should have enough RAM, Processing capability, etc to support the virtually formed machines. Today Virtualization is of many types like Platform Virtualization, Application Virtualization, Memory Virtualization, Network Virtualization, etc. The concept of virtualization is based on forming an environment which acts as base for running other applications over it. In Platform Virtualization, the virtualization is done on host computer by installing control programs which simulated a physical computer system. Now the user can install guest software over the virtual environment. The control program allows the user to assign the memory, processor, restricted access to peripherals. Application virtualization allows applications to run in environments that do not suit the native application. We can run incompatible applications on an OS easily. For example, we can run Windows applications in Linux with help of virtualization software. Hence there is no need to install other OS with which the application is compatible. There are some limitations of this type of virtualization i.e. not all the applications can be virtualized, so that they can run on the target OS. Some of the software which help in application virtualization includes Microsoft Application Virtualization, Wine,etc. Virtualization also plays an important role in managing memory in Network servers. This is done with the help of Memory Virtualization. It helps in arranging the memory of different servers on network in such a way that they act as one entity. Thus they help in sharing the memory of servers. This helps in building the combined virtual server with large amount of memory available. It also helps in improving the performance of applications on server as there is sufficient amount of memory available to them. With the help Network Virtualization networks can also be virtualized. It helps in combining the hardware and software resource over network in to a virtual network. The network hardware like Network Interface Cards (NIC) and software like Virtual Machines are used in forming a Virtual Network. For example, Microsoft Virtual Server can be used for running different OS like Windows and Linux over the network. It allows the administrator to control the bandwidth and resources to be shared among the network. The most common software used these days for Virtualization on Windows is Virtual Box. This application can be easily installed on Microsoft Windows XP, Vista and the latest Windows 7 too. After installing you can install any operating system over the installed one. You do not have to install the operating on any separate partition. It is installed just like an application is installed on your system. There is no need to restart the computer to run the new OS as it runs in a new window in your OS. For example, if you want to run some programs which are not compatible with Windows Vista which is already installed on your computer then you can install Virtual Box Software and install Windows XP on Windows Vista. There are many other programs available which help you run specific programs not compatible with your OS. One such program is DosBox. This program simulates the MS Dos which help you run old Dos application over new OS like Windows 7. This program helps in running even the 8 bit color applications which are not supported in new Windows. Now many companies have started including virtualization feature in their applications like the latest Microsoft Windows 7. In Windows 7 user can set the compatibility mode of a program with Windows XP, Windows 98, etc so that the program can run without any errors. We can also install Virtual PC in Windows 7 and run Windows XP which is available as freeware from Microsoft. Virtualization has many advantages in IT some of which are listed below: 1. One of the biggest advantages is cost savings because with Virtualization a single system is enough for many operations therefore the cost of hardware is reduced to much extent. 2. With virtualization the computer resources are used in better way and to the maximum. 3. It has helped reduce the server costs in networking. 4. It has helped in software development as the developer can test the applications on multiple platforms on the same hardware. 5. The power consumption is also reduced drastically. In the end it can be concluded that Virtualization has a very bright future in information technology as it helps to make the best use of the available system resources and get the maximum out them. Author- Bob Matharoo @ dreadbob.blogspot.com I am a Blogger who loves to write and share whatever I learn in this world on my Cute lil’ Blog called $ Secret Money Blog $. You can find Blogging Tips, Tech Reviews and some assorted randomness from the web on my blog. You can visit me at http://dreadbob.blogspot.com Bob Matharoo (General)