What Is VDI?

How virtual desktop infrastructure works

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Virtual desktop infrastructure (VDI) is a virtualization technology that uses a centralized server to host an operating system (OS) and software that desktop terminals, personal computers, and even mobile devices can access remotely and through the cloud. The OS is hosted on the server, and all of the computing that occurs on the terminals and devices is done by the centralized server. The people using the terminals and devices can use and interact with the OS as if the software was loaded on the individual computers and devices.

How Does VDI Work?

A hypervisor is a process that separates the computer’s operating system, software, and applications from the underlying physical hardware, allowing the host machine to share them with multiple devices through an internet connection. The computer that runs the hypervisor is called the host machine, and each virtual machine is called a guest machine.

There are two types of VDI, persistent and nonpersistent.

  • Persistent VDI, or one-to-one, gives each user the ability to customize the desktop image, giving the user the ability to log in to the same desktop for each use. This is similar to using your own computer.
  • Nonpersistent VDI, or one-to-many, provides a single standardized desktop environment reverts back to the standardized image once the user logs out.

The Evolution of VDI

Computer usage first began with large mainframe computers with separate terminals sharing the system through cables. These terminals were soon replaced with personal computers that allowed people to work on individual machines. The time required to maintain, update and manage the software on multiple computers soon became overwhelming for corporate information technology (IT) departments. VDI is similar to the mainframe model, with a single computer hosting all of the software, which is shared virtually, rather than by cables, to other devices.

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What Are The Benefits of VDI?

  • Centralized and simplified IT desktop management. Rather than updating software, installing patches and performing routine backups on individual computers, these tasks can be done once on the host computer. This gives the IT department the ability to manage hundreds of desktop virtually, rather than each device individually.
  • Saves money on computing resources. By loading all of the software, applications, memory, network bandwidth, and software to the host machine, guest machines have access to these resources collectively, without the costs of paying for installation on each individual machine. This can offer significant savings, not only in the upfront cost of the software but also in licensing and support costs.
  • Allows the use of outdated and cheaper machines. With the host computer doing all of the advanced computing activities, cheaper, less advanced machines can be purchased or re-used as guest machines.
  • Remote access and mobility. VDI accommodates people who are working remotely by offering the ability to access their desktop from anywhere on any device regardless of location.
  • VDI is more secure than a non-VDI environment. Data is stored in a single data center, rather than on each individual machine. In case of a breach, servers can be locked down in a more controlled manner to help minimize the damage. Guest machines are less vulnerable to breaches, as all data is stored remotely in the data center, which tends to have better controlled and monitored security capabilities.

What are the Drawbacks to VDI?

  • Storage is expensive. With VDI, the OS, applications, data, and settings for each user are stored in the data center, rather on the individual device. This data adds up and storage costs can rise quickly.
  • Internet connectivity must be fast and reliable. VDI only works with an internet connection, and weak connectivity will slow users down. This can be difficult for applications that require graphics applications which have high processing demands.
  • Complications with licensing. Software licensing and support agreements may not allow for software to be shared.

What Do You Need to Create a VDI?

The key ingredient to creating a VDI network is virtualization software that will run on the host machine. In addition to providing the host computer with the virtualization capabilities, the software must also provide the ability to administer the application, assigning and controlling the delivery of the software to the guest machines. Some solutions have evolved as cloud-based solutions that require a monthly flat fee. There are also hybrid solutions that combine on-site virtualization software with a cloud-based solution.

Who Provides Desktop Virtualization Software?

Following is a list of software companies who offer VDI solutions. Each one offers similar capabilities with a variety of different nuances that can be tailored to match the specific needs of the enterprise.

  • VMware is available on-site, in which the software is installed in the customer's own data center. If users' prefer, VMWare can also be used as a cloud solution
  • Amazon Workspaces (AWS) is a cloud-only solution, offering a managed desktop computing service.
  • IBM Cloud is a cloud solution that includes an intuitive graphical interface that makes it easy to be used by a mobile workforce.
  • Microsoft VDI offers the ability for multiple users to work remotely from only one copy of windows.
  • Oracle VM Virtual Box is a free and open-source hosted hypervisor.
  • Citrix is a virtual app that allows workers to be located remotely.

VDI allows office networks, OS and software to be moved to the cloud so that IT departments can more easily manage their computer resources, while giving employees access to the computer resources they need, regardless of their device or location.