An Introduction to Virtual Machines

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Virtual Machines (VM)

If you enjoy dabbling in computer science and building new computers, you may have come across the concept of virtual machines (VMs). Computer Science enthusiasts will be excited to know, or be reminded of, the idea that most modern-day computers are powerful enough to run whole other operating systems within the original operating system of those computers. That is essentially what a virtual machine is, and they have become more prevalent in the last decade. For example, a user could be using Windows 10 64-bit on their computer, but with enough processing power and memory storage, that user can also run a Linux OS distribution and a version of Mac OS side by side on that same computer.

What is a Virtual Machine?

A virtual Machine is a logically emulated representation of a full computer system environment. Virtual machines operate based on real computer architectures, including CPU, memory, and input/output specs. The implementations for these specs may involve specific hardware, software, or a combination of both for the implementation of the full environment.

Virtual Machines can be classified based on the degree of implemented functionality for a targeted goal or device. In this way, we can say that system virtual machines can also be called full Virtualization VMs, as they are a total substitute for a real machine, complete with the ability to execute a fully functional Operating System. On the opposite end of that are process virtual machines, designed to execute a single application within an abstracted program execution environment, independent of platform.

When it comes to making a Virtual Machine, there are several different techniques depending on the use-cases. One such technique is Native Virtualization (or “bare-metal”), which is based on directly interfacing with the underlying hardware architecture of a host computer. Relying on the raw hardware to virtualize an environment provides one with multiple instances of the same architecture, allowing a user to run whole operating systems on one machine.

Other Virtual Machines emulate different architectures, allowing for the execution of applications and operating systems made for a different CPU or architecture.

Another, operating-system-level virtualization, allows for a set of resources on a computer to be partitioned for multiple user instances via kernel’ s support. These multiple user spaces are usually called containers and may look like isolated real machines to each end user.

Lastly, some computer architectures allow for efficient full virtualization by using hardware capabilities specific to virtualization in what is called hardware-assisted virtualization.

Read: Virtual Machines (VM) and Understanding Virtualization

What are the Benefits of Virtualization and Virtual Machines?

There are many use-cases for virtualization and virtual machines themselves. Enterprises of all sizes can benefit from combining virtualization and cloud computing technologies, directly taking advantage of the availability of a network without the cost of running (and owning) hardware. Virtual machines are perfect for small to mid-sized organizations in need of low-cost and reliable service or businesses looking to grow (or expecting growth in the near future) for example.

Ultimately, the goal of cloud computing is to allow users to take advantage of all these technologies and more without having an expertise knowledge in any of them. The cloud aims at cutting costs, superseding otherwise impeding obstacles in IT, allowing users to focus on core business tasks. What enables cloud computing is virtualization, as it splits a physical machine into several more virtual devices, each of which can be utilized for various computing jobs.

For example, operating system-level virtualization provides the means of creating a scalable system where idle computing resources can be allocated to other tasks. It also provides the agility needed to speed up IT operations, increasing infrastructure utilization while decreasing costs. Automation, too, becomes readily deployable where jobs like provisioning resources to users can be well automated, reducing labor costs and speeding up the relevant processes.

Read: Expert View on Virtual Machines: Use Cases and Future Trends

Virtual machines are also useful in the research setting, as computer scientists from Sandia National Laboratories have shown by demonstrating that a million Linux kernels can be run as virtual machines. The significance of this achievement means that security researchers can more effectively observe and track the behavior of malicious botnets (networks of infected devices that can grow to the scale of millions). These botnets are difficult to analyze, considering that their victimized nodes are geographically spread across the world. This example is just one such way researchers can utilize virtual machines for their studies.

If you want to take part in virtualizing a project and using virtual machines in your everyday life, there are many options available for virtual machine applications on Windows, Macs, and Linux desktops. The act of setting up and running Virtual Machines with different operating systems allows one to experience and learn from each of them. Try running Linux on your Windows computer, or Windows on your Mac OS device. VM applications do not need you to install a new operating system on your hard drive. What happens instead is that the new OS is run in the host memory on a virtual copy of the available host hardware. A VM can help test out new ideas, tools, projects, or for secure computing, and more.

Some of the most popular Virtual Machine applications are:

Read: Containers vs Virtual Machines

William Hreiki
William Hreiki
William Samer Hreiki is an IT professional with experience in logistics, web development, and cybersecurity. After studying political science abroad, he achieved a certificate in cyber-criminology at Boston University and a Master of Science in Cybersecurity at Northeastern University. Dedicated to aiding in networking and development best practices, William immerses himself in projects involving Internet of Things and Blockchain technology. In his spare time, he enjoys 3d modeling and exercising.

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