If you want to allow user access to an RDS Collection or RDS Components of a Windows Server operating system, you need to purchase additional licenses. Typically, the RD Session Host (RDSH) server hosts the resources such as Windows applications or files, and clients connect to the RDSH to access those resources.
The actual RDSH hosting the resources must have a Windows Server CAL that matches the OS version. Remote client devices accessing the server must have a user CAL. With newer RDS CALs, you can access older RDSH servers. But things tend to be different with older RDS CALs since they can’t work with new RDSH servers, and you have to purchase new licenses.
You need an RD Licensing Server to install and keep track of the RDS CALs. Just as a quick reminder, the RD Licensing Server is a component of the RDS Collection. When a user tries to connect to an RDSH server, the server checks to see f the user has an active RDS user CAL by contacting the RD licensing server. If available, the RDSH sever accepts the connection from the use and starts a session.
While the purpose of all RDS CALs is the same, there are different approaches to these licenses. RDS CALs license come in two forms: RDS per-device CALS and RDS per-user CALS. Choosing one type of CAL over another depends on whether users typically initiate remote sessions from the same device or not.
To have a better understanding of the two types of RDS CALs, it is essential to examine the main differences between them. In a nutshell, RDS CALs can be tracked using Per Device, while they can’t be tracked withing a workgroup for Per User. Not to mention, up to 20% of RDS CALs can be revoked in Per Device, but this is not possible in Per User.
With Per Device, each device has RDS CALs physically assigned to them. In Per User, RDS CALs are assigned in Active Directory. Remember, it’s not possible to over-allocate RDS CALs when using Per Device, but overallocation may take place with Per User.
So, how do you determine the precise RDS device CAL for an organization? For this to happen, IT teams should calculate the maximum number of simultaneous remote sessions required. This straightforward number should determine how many CALs are needed for any RD Licensing server to manage.
Of course, you should always keep in mind that Microsoft sells its RDS CALs on an individual basis or in license packages of five and 25. Th Company negotiates some set number of CALs as part of overall volume licensing agreements.
As we conclude, an RDS CAL is a license that allows users/devices to access and utilize Windows Server published resources, such as Windows applications, desktops and files. This license model offers a way to pay for capacity. The more devices or users accessing your resources, the more RDS CALs you need.