When a Windows client device connects to a published desktop or application on an RDS host, it receives an RDS Per-Device Client Access License (CAL), if the Per-Device licensing mode is configured on the RDS host.

By default, the CAL is stored only on the client device.

Note: Storage of Per-Device CALs is supported only on Windows clients. Windows Zero clients, and non-Windows clients, do not support this feature. For clients that do not support this feature, CALs are stored only on the Connection Server host.

Storing the CAL makes CAL use more efficient in RDS deployments and prevents the following problems.

  • If you deploy multiple license servers, and users run multiple sessions from a client device that connects to different RDS hosts that use different license servers, each license server can potentially issue a separate RDS Per-Device CAL to the same client device. If a license server services both Windows Server 2008 R2 RDS hosts and Windows Server 2012 or Windows Server 2012 R2 RDS hosts (issuing both Windows Server 2008 R2 CALs and Windows Server 2012 or 2012 R2 CALs), a single client device can use up as many as two CALs for each license server in your deployment.
  • If you have Windows 2012 or 2012 R2 CALs installed on a Windows Server 2012 license server, a client device that makes a PCoIP or VMware Blast connection to a Windows Server 2008 R2 RDS host is always issued a temporary license, even after multiple connections are made. A permanent license is never issued for the client.

Considerations for Cloud Pod Architecture Environments

A typical Cloud Pod Architecture environment consists of multiple pods. Each pod can point to a different license server, and a single client device can use published desktops and applications on different pods in the pod federation.

Beginning with Horizon Client for Windows 4.9, if the client device has a license, it always presents that license. Windows clients that have Horizon Client 4.8 or earlier present a license only if they have a license for the specific pod. If the client device does not present a license, the most up-to-date license that can be found on any pod involved in the published desktop or application launch is used. If a license cannot be found on any pod involved in the launch, the client device's ID is presented to the license server and a license is issued.

Important: VMware recommends that you upgrade to the latest Windows client and server software for the best handling of RDS licensing.