Using Windows Server Versus Client for VDI Desktops

Using Windows Server Datacenter edition as the basis of a virtual desktop infrastructure (VDI) and using Windows Server as the desktop OS can significantly impact how access to virtual desktops is licensed.

Shown here are two VDIs that use Microsoft’s Remote Desktop Services (RDS) technology to enable remote access to virtual desktops running in virtual machines (VMs). (RDS technology is used by Windows Server to provide Microsoft’s VDI solution, and it is also used by many VDIs from third parties, such as Citrix.)

The top VDI hosts virtual desktops in VMs that are running Windows Server, while the bottom VDI hosts virtual desktops in VMs that are running a Windows client OS, such as Windows 7 Professional or Enterprise edition.

In the top VDI, the host servers are licensed with Windows Server Datacenter edition (US$6,156 per server). The unlimited virtualization rights of Windows Server Datacenter permit the organization to run Windows Server desktops in any number of VMs on the server. Each user or device needs two Client Access Licenses (CALs): a Windows Server (WS) CAL (US$34 per user or US$30 per device) and an RDS CAL (US$118 per user or US$102 per device). (Prices listed are U.S. Open No Level, typically the highest price that a U.S. customer would pay in volume licensing.)