Virtualization, as we all know in IT landscape, isn't something that is new to technology. In fact, its history goes back to the early 1960s when IBM came forward with the concept of virtualization to run numerous software environments on its mainframe. At that point of time no one ever knew that this technology would emerge and gain paramount significance for the IT industry after 54 years.

Virtualization has become a key component of the cloud technology as it completely transform IT resource utilization by treating your company's physical resources as pools from which virtual resources can be dynamically apportioned.

 Simply put, virtualization is a technique through which computing resources (CPU, memory, storage, network and so on) are abstracted from users and applications. Albeit virtualization is not a prerequisite for cloud hosting, yet cloud service offerings without virtualization are not very typical.

Through this post, I would like to highlight what exactly is hypervisor and how cloud virtualization can be achieved by means of hypervisor.

What Exactly is Hypervisor?

A hypervisor is virtualization software that enables several operating systems (OS) to pool the resources of the same physical server. In fact, these physical servers are referred to as the host servers. Virtual machines (VM) are basically software-defined abstractions of the hardware. As VMs are detached from the underlying hardware components, it becomes quite simple to shift VMs from one physical server to another. Cloud computing relies greatly on this attribute owning to dispersed nature of computing environments and operations.

It is also referred to as virtual machine manager (VMM).

Different Types of Hypervisor:

Hypervisors can be classified into two main types:

Bare Metal Hypervisor- A bare metal hypervisor operates directly on the physical server. It has comprehensive control over the server's resources and can apportion resources to guest's operating systems or VMs whenever required. VMs function over the bare metal hypervisor. Ultimately, all the critical business applications run on the VMs like any other OS. Typically, these applications are not cognizant of the virtualization. The underlying key hardware components are abstracted from the applications operating on VMs. However, it is imperative to commit to memory that there are two stratums of software stack in a bare metal hypervisor.

Hosted Hypervisor- On the other hand, a hosted hypervisor has got three stratums of software stack. They are- a host OS that runs directly on the physical server; hosted hypervisor that operates a level above the host OS (both the hypervisor and traditional non-virtualized applications operate on a host OS); on the final stratum, VMs runs above the hosted hypervisor. And, these VMs comprise of users OS and business critical applications.

Therefore, the hypervisor is a very handy and discreet way of getting things virtualized swiftly and proficiently. In a nutshell, experience increased operational efficiency, flexibility and responsiveness by embracing cloud virtualization.