One of the first things to do when preparing for your XenApp 6.5 installation is to configure the infrastructure services, in this case, licensing. XenApp 6.5 requires that you have a licensing server version 11.9 or higher. If you have an existing farm you may already have a License Server, but make sure that it is 11.9 or upgrade it.
Once installed the server will listen on TCP ports 7279, 8082 and 27000
Licenses are concurrent user for XenApp and can be shared across farms if all servers use the same license server. Microsoft Remote Desktop Licenses are required but are separate from Citrix licensing. Citrix licenses are imported to the server web console and are issued to the case-sensitive name of the License Server. I hope the video helps.