Microsoft VDA & RDS Licensing

When building out a new Horizon View or DaaS solution there is always one other complex licensing structure to remember… licensing the actual Windows desktop OS.

To license a virtual Windows desktop OS you need a special license from Microsoft is called VDA or Virtual Desktop Access.

One important note to mention here is that VDA does not apply to a skinned server OS or Linux OS so if your building a new VDI or DaaS solution you may want to choose a “Server Desktop” option.  If you do decide to deploy a dedicated Windows Server OS within the VM for every user as their VDI desktop, please note that you will need to purchase an RDS-CAL (Windows Server Remote Desktop Services Client Access License) to correctly license that scenario.

However, if you don’t take the “Server 2008 R2/2012 Desktop” route and go down the “Windows 7/8/XP” path there are a few ways to gain VDA rights.  One, if a customer has Software Assurance for a Windows client they are granted the VDA licensing rights. Two, they simply purchase a VDA subscription to run Windows (7,8,XP) as a virtual machine. Three, if its a larger enterprise customer and they have a Microsoft Enterprise or Select agreement they can look into the CSL route.  This is confusing so I’ll go into each of these scenarios a bit more in detail.  See flow cart below to also help guide you to the appropriate path to take.




VDA licensing actually applies to the device used to access the Windows virtual desktop.  


1.) The first question to ask is if the access device is the primary work device.  One device must be designated as an employee’s primary access device.  If the access device is considered the primary device and that device is running a qualifying Windows OS itself, the customer has the option of licensing via SA, or if they don’t have or don’t want to buy SA, they must buy a VDA license.  If the primary work device is not running a qualifying Windows OS, the customer’s only option is to buy a VDA license. If the access device is not the primary work device, the next question is about the user.


2.) Is the user already covered by SA or have a VDA license associated to them and their primary work device?  If not, then the customer must have SA or buy a VDA license.  If there already is SA or VDA associated to them and their primary work device then we’re on to the 3rd question.


3.) Is the access device owned by the company?  If it is, there are 3 possible outcomes as shown in the flowchart above – VDA/SA, or CSL, or do nothing.


4.) The 4th and final question is about the location of the access device. If the access device is used to connect via the corporate network, the company must buy a CSL for the device.  If it is not used to connection from the corporate network, the company does not need to buy anything.