How do virtual desktop infrastructure (VDI) solutions stack up to the traditional way of doing desktops, which means locally-installed copies of Windows running on regular PCs or laptops scattered throughout an organization? That's the question I answer in this installment of my VDI series.
Part two of this series compared and contrasted VDI solutions to server-based computing (SBC) solutions such as Citrix Presentation Server or Microsoft terminal services.
VDI essentially lets you "SBC-ify" your traditional local desktops. Users can access them from any device over any connection. You get the best of both worlds.
VDI offers these advantages over traditional local desktops:
- Access your real desktop from anywhere. One of the greatest benefits of SBC, and by extension VDI, is that a user can access their applications (or their desktop in the case of VDI) from just about anywhere. Any connection. Any client device. Anywhere in the world. Why wouldn't you want to extend that power to the desktop, too?
- Ease of management. If you have to manage 1,000 desktops, which would you rather manage: 1000 physical desktops scattered all over the place, or 1000 VMs and VMware disk images in a single data center? The simple fact that the client "workstations" are all in the datacenter can have a profound effect on management, patching, provisioning, etc.
- Easier backups. All you would have to do is to backup the "workstation" would be to backup or snapshot the disk image files on the server. Then if a user lost something, it would be simple to "roll back" their laptop to whenever they wanted. You could even take this a step further and provide an automatic snap-shotting service that did this once an hour.
- Data containment. With VDI, you can guarantee that important files and data do not flow across the network to be stored (even accidentally) on the client deivce itself.
- Desktops run on server-class hardware. Since desktop computers are distributed throughout an organization, they don't have the same redundancy as server-class hardware. A single power supply, drive or memory failure can take down a desktop computer. Of course, the same also applies to servers. However, since there are fewer servers in an organization than desktops, it's okay from a financial and risk standpoint to spend money on redundant power, RAID and other technologies to ensure that server hardware doesn't have the same potential hardware failures.
Traditional local desktop approaches offer these advantages over VDI:
- Offline use. The biggest downside of VDI is that your client device, while it can be just about anything, must have a network connection to whatever backend server is running your Windows XP session.
- Better performance for graphics-rich applications. VDI solutions are "more compatible" with a lot of applications since your apps are each running on their own Windows XP workstation instead of a shared terminal server. This "solves" a lot of application compatibility problems such as performance hogs and non-terminal server compatible applications. However, at its core VDI is still a flavor of SBC, which means that the application's graphical screens have to be transmitted across the network from the back end to the client. This means that application that are video or graphic-intensive may still not work well, even though they're running on a Windows XP VM.
- It's the de facto standard. In the same vein as "no one ever got fired for buying IBM," the reason we call this method "traditional local desktops" is, well, because it's just the way things are done today. You don't have to implement anything or rock the boat or try anything new. You can "choose" this option by continuing to do what you're doing today.
In summary, you can see that VDI lets you have many of the advantages of traditional computing while adding some of the advantages of server-based computing. Of course, when compared to traditional desktop computing, VDI's network connectivity requirement can be a show stopper.
In the next article of this series, we'll take a look at where VDI technology makes sense in today's world and how you can figure out whether it makes sense for you.
About the author: Brian Madden is an independent technology analyst, author, and thinker based in Washington, DC. He's written several books and hundreds of articles about Citrix and thin-client computing technology. Brian is a three-time Microsoft MVP, a Citrix Technology Professional (CTP), and he currently speaks and teaches throughout the world.
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