VDI or RDS – Which Desktop Distribution Platform is Right for You?

If you have a pool of users that need access to Windows desktops, you can deliver those desktops and associated applications remotely, saving money on administration and end-user hardware alike, while gaining control over security and access control.

Two methods to achieve this are Virtual Desktop Infrastructure and Remote Desktop Services. In either case, the user connects to a server or virtual machine which is hosted within a data center or with a cloud provider. That remote server or VM contains the desktop environment and all data and applications are stored and processed remotely.

But is VDI or RDS the right choice for your situation? Let’s take a look at the differences between the two and some use cases for each.

Remote Desktop Services

RDS evolved from Terminal Services, a Windows proprietary feature that is based on Citrix technology (in fact, Citrix wrote and licensed the code). You run a single Windows Server instance, either on hardware or a virtual server, and users access it via network connection and Remote Desktop Protocol. All processing takes place on the server itself and not on the local user machine, and all instances run simultaneously on that single server.

RDS is limited to Windows Server for obvious reasons. The desktop image you configure on the server is cloned and presented to the user with all of its associated applications and data. This can be individualized based on login credentials or simply be a basic, one-size-fits-all instance.

All users generally have the same OS and applications presented to them, but with Win Server 2016 and newer, Personal Session Desktops allow for some persistency. RDS subscriptions might include the necessary licensing, which is temporarily assigned to each user as the access the desktop.

Virtual Desktop Infrastructure

With VDI, you configure a pool of virtual desktop servers using virtualization software like VMware Horizon View or XenDesktop. These tools are not limited to a single operating system like Windows, or a single application architecture.

Each user receives their own virtual server rather than everyone running on a single server as with RDS. The VDI VM hosts an individual OS instance with associated applications and data. This means that each VM in the pool must have its own license for the OS and the applications therein, adding some complexity both to management and licensing. However, a single master image can be configured and updated to simplify ongoing administration.

VDI can work either with persistent or nonpersistent desktops. Persistent desktops allow for personalization and, if you wish, can even have custom application installs and OS configurations. With nonpersistent desktops, users are randomly assigned an available desktop from the pool. While those desktops can be preconfigured with profile data, that profile data must be stored either on attached network storage or on the end client.

Weighing Your Options

Assuming you are planning to run Windows desktops, much of the decision comes down to the number of users, licensing, security, and performance. The applications in use are also a major consideration.

RDS simplifies administration and licensing as they are less moving parts: it’s a single server to maintain and licensing is linked to each user via Client Access License. With VDI, you probably need to tie licensing to the number of VMs you anticipate using in production, especially with a nonpersistent deployment, because different users may use the same desktop.

Either option can support vast amounts of users. For simple desktop applications like Office, e-mail, or other non-intensive productivity software, RDS is likely to be a less expensive and simpler option. With a powerful enough server or VM, you can run 100s instances with solid performance.

If your users require personalization, custom applications, or intensive applications like graphics or video editing, 3D modeling, or heavy data processing, then VDI is likely to be the better option. Licensing can be trickier and potentially more expensive, however.

Because all users share a single server, RDS could be less secure than VDI. For performance and compliance, VDI is a better solution.

VDI usually provides stronger resilience and redundancy when properly configured, as the virtual servers can failover or be restarted on a fresh host. A single network issue or outage can take down every user on your RDS box.

Key questions to guide your decision-making include:

• Do I only have a small amount of users accessing remote desktops, or am I applying this to the entire organization?
• How many users will need full or higher levels of control over their desktop? How many users only use basic applications vs. power users who require more performance and customization?
• Do I have any applications that don’t play nice with Windows?