This post, explain the underlying technology behind the publishing refresh implementation in server side. 

First of all, keep in mind that you can do Publishing Refresh only if you have a configured App-V Management Server in your client.  When you click “Refresh Server” from the client management console or login to your account or a prescheduled publishing refresh arrives, your client sends a publishing refresh request to the network which now contains a RTSP(S) packet whose IP address is the IP address of the management server[…]

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