Taxonomy of virtualization techniques in cloud computing

• Hardware Virtualization
• Operating System Virtualization
• Application Virtualization
• Storage Virtualization
• Network Virtualization
• Memory Virtualization
• Hardware Assisted Virtualization

Hardware Virtualization

1. Full Virtualization

• In full virtualization, a hypervisor (also known as a Virtual Machine Monitor) sits between the hardware and the operating system, creating a complete virtualized environment.
• Virtual machines (VMs) run independent operating systems, unaware of the underlying hardware.
• Examples include VMware ESXi and Microsoft Hyper-V.

2. Para-Virtualization

• Para-virtualization involves modifying the guest operating system to make it aware of the virtualization layer.
• This collaboration between the hypervisor and the operating system results in improved performance compared to full virtualization.
• Xen is a common example of a para-virtualization hypervisor.

Operating System Virtualization

Containerization

• Containerization provides lightweight virtualization at the application level.
• Containers share the host operating system's kernel but maintain separate user spaces, allowing for efficient resource utilization and rapid application deployment.
• Docker and Kubernetes are popular containerization technologies.

What is Docker?

What is Kubernetes?

• Kubernetes is an open-source container orchestration tool.
• It automates the process of deploying, scaling, and managing applications stored in containers.
• Kubernetes works seamlessly with container technologies like Docker.

Hardware-Assisted Virtualization

• Hardware-assisted virtualization utilizes specific features in modern processors to enhance virtualization performance.
• Intel VT-x and AMD-V are examples of hardware virtualization extensions that improve the efficiency of virtualized environments.

Network Virtualization

• Network virtualization abstracts networking resources, allowing the creation of virtual networks within a physical network infrastructure.
• VMware NSX and Open vSwitch are examples of technologies that provide network virtualization, enabling the isolation and segmentation of network traffic.

What is Vmware NSX?

What is Open vSwitch ?

Application Virtualization

• Presentation virtualization, also known as application virtualization, separates the execution of software from the end-user device.
• The application runs on a server, and only the user interface is transmitted to the client.
• Example: Citrix XenApp is a presentation virtualization solution.

Memory Virtualization

• Memory virtualization allows the allocation of more virtual memory than physically available.
• Memory overcommitment techniques, such as page sharing and compression, optimize memory usage.
• Example: VMware ESXi uses memory overcommitment for efficient resource utilization.

Storage Virtualization

Block-level Virtualization

• Block-level virtualization abstracts storage devices into virtual blocks, allowing them to be managed independently.
• Example: Storage Area Networks (SANs) often use block-level virtualization.

File-level Virtualization

• File-level virtualization operates at the file system level, abstracting physical file locations.
• Example: Network Attached Storage (NAS) systems leverage file-level virtualization.

What is Hypervisor ?

• A hypervisor, also known as a virtual machine monitor (VMM), is a crucial component in the field of virtualization.
• It is software or firmware that enables the creation and management of virtual machines (VMs) on a physical host machine.
• The primary purpose of a hypervisor is to abstract and allocate the physical hardware resources.

Types of Hypervisors

• Type 1 Hypervisor (Bare-Metal Hypervisor)
• Installs directly on the hardware and operates without the need for a host operating system.
• Example: VMware ESXi, Microsoft Hyper-V Server, and Xen.
• Type 2 Hypervisor (Hosted Hypervisor)
• Installs on top of a host operating system and relies on it to manage hardware resources.
• Example: VMware Workstation, Oracle VirtualBox, and Parallels Desktop.

Conclusion