Windows Server: An Overview of Windows Remote Desktop Services Licensing

Article Summary: This article provides an overview of licensing for Remote Desktop Services in Windows Server.

Windows Remote Desktop Services (known as Terminal Services in Windows Server 2008 and earlier versions) has three licensing modes:

• Remote Desktop for Administration: This licensing mode allows for up to two administrative sessions, including the local console session, to be running simultaneously on a Windows server. This is the only licensing mode that does not require Remote Desktop client access licenses (RD CALs) or a license server. It is intended to allow administrators to connect to a Windows server remotely in order to perform administrative tasks. A server is in Remote Desktop for Administration licensing mode if the Remote Desktop Session Host role service is not installed.
• Per User: This licensing mode requires an RD CAL for each unique user that will connect to a Remote Desktop Session Host server, regardless of the number of devices from which that user will connect.
• Per Device: This licensing mode requires an RD CAL for each unique device that will connect to a Remote Desktop Session Host server, regardless of the number of users that will connect from that device.

The appropriate licensing mode for a particular RD Session Host server depends on multiple factors, such as the number of users and unique devices that will establish Remote Desktop sessions to that server.

The Per User and Per Device licensing modes require that a server in the environment be configured with the Remote Desktop Licensing role service, and that RD CALs be purchased and applied to the license server. 

There are two types of RD CALs, corresponding to the two license modes that require them. An RD Session Host server can only be in one license mode, but a license server can have CALs of both types installed in order to support multiple RD Session Host servers.

A Remote Desktop Session Host server must be configured to use a particular license server; an RD Session Host server will not automatically detect a license server, even if the RD Session Host and RD Licensing role services are both installed on the same server. The licensing mode and license server are both configured in the Remote Desktop Session Host Configuration console. More information on using this console to configure license settings can be found in Configure License Settings for an RD Session Host Server.

One important item that is often overlooked is that Remote Desktop CALs are required to use any component of the Remote Desktop Services role, not just RD Session Host. Other components that require CALs include Remote Desktop Gateway, Remote Desktop Web Access, and Remote Desktop Virtualization Host, as explained in Licensing Windows Server 2012 R2 Remote Desktop Services (PDF), which applies to previous versions as well. This does not include Remote Desktop for Administration, though, as specified above.