Brief introduction of the development course of virtualization Technology

This article will provide a detailed introduction to the development of virtualization, virtualization technology in the cloud computing era, server virtualization, Application Virtualization, and Systemcenter management of virtualization.

Virtualization Development Process:

The concept of virtualization for the first time was in the 60 's in the 20th century, and it could be used to partition the mainframe hardware for scarce and expensive resources. Over time, microcomputers and PCs can provide a more efficient and economical way to allocate and process resources, so until the 1980s, virtual technology is no longer widely used.

But by the 1990s, researchers began to explore how to use virtualization to solve some of the problems associated with the surge in cheap hardware, such as inadequate utilization, rising management costs and vulnerability. Virtualization technology is now at the forefront of the times to help companies upgrade and manage their IT infrastructures around the world and ensure their security. Virtualization technology can increase the capacity of the hardware and simplify the reconfiguration process of the software. The virtualization technology of CPU can simulate multiple CPUs in a single CPU, allow a platform to run multiple operating systems simultaneously, and the application can operate in separate space without affecting each other, thereby significantly improving the efficiency of the computer.

The cloud computing platform includes three types of services: The software infrastructure is the service IaaS, the platform is the service PAAs, the software is SaaS, and the three types of services are based on the virtualization platform, and the relationship structure is as shown in Figure 1 below:

There is no doubt that virtualization is reorganizing the IT industry, and it is supporting cloud computing, and it is also a matter of understanding virtualization, which is impossible to achieve on-demand computing without virtualized cloud computing.

Virtualization Technology

Virtualization is a logical representation of resources, a representation that is not constrained by physical constraints, and its primary goal is to simplify the presentation, access, configuration, and management of IT resources, including infrastructure, systems, and software, and to provide a standard interface for these resources to receive input and provide output.

Virtualization technology includes two levels, one is the hardware level of virtualization, and the other is the software level of virtualization. In fact, what we usually call virtualization is the server virtualization technology, in addition to the application layer, presentation layer, desktop, storage and network can do a full range of virtualization, the type of virtualization can be shown in the following figure:

Types of Virtualization

(1) Network virtualization

Network virtualization typically consists of virtual LANs and virtual private networks. Virtual local Area Network is a typical representative, it can divide a physical local area network into many virtual local area network, or divide the nodes in the physical local area network into a virtual local area network, provide a flexible and convenient network management environment, make the large network easier to manage, Network optimization can be achieved by centralizing the physical devices in different locations.

Virtual private networks help administrators maintain IT environments, prevent threats from intranet or extranet, and enable users to access applications and data quickly and securely. At present, the virtual private network is used in a large number of office environments.

(2) Storage virtualization

Storage virtualization is the process of creating physical storage resources for a host. With virtualization technology, multiple storage media modules (such as hard disks, RAID) are centrally managed through a number of means, all of which are uniformly managed in one storage pool. Redundant Array of independent Disk, (RAID) technology is the embryonic form of virtualized storage technology, and the storage currently used is receptacle Checkmark Storage (NAS) and Storage area receptacle ( SAN).

(3) Desktop virtualization

Desktop virtualization technology, the definition on Wikipedia is: "Desktop virtualization (or Virtual Desktop infrastructure) is a server-based computing model, and borrowed from the traditional thin client model, But there are two ways that administrators and users can get the benefits of hosting and managing all desktop virtual machines in a data center, while users can get a full PC experience. The biggest advantage of desktop virtualization is the ability to use software to configure PCs and other client devices from a centralized location, which facilitates the centralized management of computers by enterprise users, and the management and control of application software, system patches and anti-virus software in the data center.

(4) Presentation layer Virtualization

Displays and operates remote computer desktops on the local computer, and performs storage information and programs on remote computers, typically through Terminal Services.

(5) Application Virtualization

Displays and operates computer desktops on a single computer, executing programs and storing information on another computer.

Currently in the Microsoft virtualization product line, already has the server virtualization, the Application virtualization, the desktop virtualization, the presentation layer virtualization product:

Server virtualization

Server virtualization can be said to be the most familiar way to have multiple operating systems and applications running on different virtual machines, which are built on the same physical server. However, the number of virtual servers on one server depends on the capabilities of the hardware, all virtual servers share the same hardware, but run independently of each other, and individual virtual servers can be upgraded, booted, and not affected by other virtual servers.

Server virtualization solves the problem of the physical server environment, through the virtualization layer can isolate the same machine, different operating systems running programs, to avoid resource conflicts. In addition, server virtualization can dynamically move underutilized hardware resources to programs most in need of application, thereby increasing the utilization of underlying hardware resources.