How does Microsoft Windows licensing affect the adoption of cloud-based desktops?
"Cloud-based desktops" can mean a few different things. First, delivering a desktop from the cloud can give mobile users that are using a non-Windows device, such as an iPad, access to Microsoft Office or other Windows applications. Cloud-based desktops may also be used by organizations that want to use secure thin terminals, rather than full Windows PCs, with common Windows applications.
There are two ways around this (somewhat mysterious) prohibition.
- Rent a hosted Windows Server desktop
- Have a managed service provider host virtual PC desktops for you
Windows Server desktops can be supplied via Remote Desktop Services (RDS), formerly known as Terminal Services. A Windows server spins off multiple desktop "sessions" that give users access to a PC-like desktop. Desktop sessions can be rented to customers on a monthly basis by a hosting provider who signs Microsoft's Services Provider Licensing Agreement (SPLA).
Because these desktops (and Office, at an additional charge) can be rented per user, they are a good way to offer Windows and Office to users with multiple devices that can't run Office natively. With one account, they can access their hosted desktop from one or more PCs, an iPad and other devices.
These desktop sessions -- or specific applications running on them -- can also be made available to users via virtual desktop delivery or application virtualization tools from Citrix or Microsoft.
The second way to provide cloud-based desktops is to pay a managed service provider (MSP) to run virtual desktops. The customer provides the MSP with virtual machines running a PC OS (for instance, Windows 7), and the MSP hosts them on its servers. Each of the MSP's servers must be dedicated to one customer in this scenario; MSPs are not permitted to host software from multiple customers on the same physical server.
So how does Microsoft Windows licensing fit into this hosting method? Customers access the virtual machines using a remote desktop protocol, but each device accessing the virtual machines must have the proper Windows licenses -- either Windows with Software Assurance (Microsoft's upgrade rights program) or a Virtual Desktop Access subscription. As a result, this solution can reduce data center management and utility costs but generates no savings in licenses.
In addition, if customers are accessing Office on these virtual desktops, each device accessing the virtual desktop must have its own Office license, which makes this scenario substantially more expensive than the services provider solution for users with multiple devices.
This was first published in April 2013