On a XenDesktop VDI I see in HKLM:\System\CurrentControlSet\Control\Terminal Server\WinStations keys "Console" and "RDP-Tcp" as expected, but also a key "EH-Tcp" with a WdName value "Microsoft RDP 5.2". This is a Windows 7 machine. What is "EH-Tcp"?
And why is there no key "ICA-Tcp"? Does XenDesktop not use ICA?
XenDesktop use the ICA channel between the VM and the endpoint via the Citrix Virtual Desktop Agent (now named Virtual Delivery agent) installed in the machine.
It's not adding any entry in the TerminalServer subkey.
EH-TCP seem to have been introduced from Vista+. Seem related to Remote-FX.
There is a diagram for XenDesktop;