Understanding the RDS CAL Model

• There are two types of RDS CAL: Device CAL and User CAL.
• RDS CAL licenses are assigned to each device.
• RDS CAL licenses are assigned to a user in the Active Directory directory service.
• RDS CALs are monitored by the license server.
• RDS CAL licenses can be tracked independently of the subscription to the Active Directory directory service.
• RDS CAL licenses cannot be tracked in a workgroup.
• You can revoke up to 20% of RDS CALs.
• Temporary RDS CALs are valid for 52–89 days.
• RDS CAL licenses cannot be over-allocated.
• When using the device model, a temporary license is issued the first time a device connects to the RD session host.
• When using the user model, licensing is not enforced, and each user is granted a license to connect to an RD session host from any number of devices.
• It is your responsibility to ensure that all your users have a valid license.
• An example of where one might use the device model would be in an environment where there are two or more shifts using the same computers.
• The user model would be best for environments where users have their own dedicated Windows device.
• RDS CAL version compatibility: The RDS CAL for your users or devices must be compatible with the version of Windows Server that the user or device is connecting to.