There are two types of RD CALs, corresponding to the two license modes that require them. Note that RD CALs are separate from server CALs, which allow other (non–Remote Desktop) methods of access to a Windows server, such as file-share access or application-based access.

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. 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. 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.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.

A server is in Remote Desktop for Administration licensing mode if the Remote Desktop Session Host role service is not installed. It is intended to allow administrators to connect to a Windows server remotely in order to perform administrative tasks. This is the only licensing mode that does not require Remote Desktop client access licenses (RD CALs) or a license server. 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.Windows Remote Desktop Services (known as Terminal Services in Windows Server 2008 and earlier versions) has three licensing modes: Article Summary: This article provides an overview of licensing for Remote Desktop Services in Windows Server.

Windows terminal services