VDI applications maintain many use-case advantages over DaaS

Although VDI and DaaS are seen as viable options for hosting virtual desktops, the two technologies are very different at an architectural level, making each better suited for specific desktop use cases.

As desktop-as-a-service technology matures, cloud-based virtual desktops have been steadily gaining traction over the last several years. The DaaS market reached $650 million worldwide in 2017 on the shoulders of an average annual growth rate of nearly 50%, with projections of becoming a $4.7 billion market by 2022, according to Market Watch.

VDI adoption rates are likewise increasing -- but at a slower rate. A 2018 Business Wire report pegged the global market for VDI applications at a 27% compound annual growth rate through 2023. Ostensibly, DaaS is quickly becoming the preferred platform, yet the larger increase in DaaS adoption more than likely is due to the technology's maturation. Gartner sees DaaS attaining "essential" feature parity with VDI this year -- albeit on different application tracks.

"IT organizations are considering cloud-based virtual desktops because of the challenge of maintaining a quality end-user experience," said Gary Bea, director of consulting services and technical operations at Goliath Technologies, an IT monitoring and troubleshooting software company. "What they find out is, though the desktops are moving to the cloud, accountability is not. But now, when solving end-user experience issues, they have to engage a third party and can't handle it directly. Instead of improving the end-user experience, there is another level of abstraction and complexity injected into the process that only causes more obfuscation and delay."

On-premises VDI applications and DaaS have their strengths and weaknesses. Depending on the environment and application, certain use cases are a better fit to each platform.

[T]hough the desktops are moving to the cloud, accountability is not.

Desktop control. VDI applications make sense for companies that need granular control over their virtual desktops and the underlying infrastructure on which the desktops are hosted. While cloud providers do allow their subscribers to make certain customizations to virtual desktops, most of the underlying infrastructure is hidden from view. That not only limits the configuration changes an organization can make, but it can also make troubleshooting more difficult. Performance or stability problems with cloud-based desktops may require the cloud service provider to troubleshoot. And, typically, it'll take longer to diagnose and resolve the issue compared to the virtual desktop hosted on premises.

Internet reliability. VDI is a better fit than DaaS in businesses that have limited or unreliable internet connectivity. Like any other cloud-based service, DaaS-hosted virtual desktops are accessed over the internet. If internet bandwidth is limited, then the end-user experience may be negatively affected. In addition, when DaaS is used, a company's internet connection can become a single point of failure. Employees won't be unable to access their corporate desktops if there's an interruption in internet connectivity.

App flexibility. VDI is a good choice to run a very specific virtual desktop configuration. DaaS providers usually offer a few different rigidly sized small, medium and large virtual desktop options, which may not be able to run resource-intensive applications on cloud-based virtual desktops. In addition, if employees use only very lightweight applications, then a company may have to pay for cloud-based resources that are going unused. VDI, on the other hand, allows a company to scale virtual desktops to meet exact needs.

OS licensing. VDI applications may be the better alternative for a company looking to transition away from physical desktops. That company presumably already owns desktop operating system licenses that can likely be reused on its VDI-based virtual desktops. Some cloud providers do allow DaaS subscribers to bring their own OS license. More often, however, the subscription price includes the cost of an OS license that the subscriber could conceivably pay extra for a license it already owns.

Data protection. VDI might be better when it comes to protecting sensitive data, since VDI-hosted virtual desktops reside on premises. Sensitive data is not being transmitted across the internet or accessed from cloud-based virtual desktops that may be monitored by the cloud provider. DaaS providers invest huge sums of money in keeping their service secure, while most companies put controls in place to prevent users from storing data directly on their desktops.