Are there any secure alternatives to XDMCP?

Question

The title says it all: Are there any secure alternatives to XDMCP (A Linux remote desktop protocol)?

I'd like to set up some thin clients -- UI heads (old computer + mouse + keyboard) connected to VMs on a fast server. ssh -Y doesn't quite cut it, since this would be for non-savvy computer users. I'd like it integrated with kdm/gdm if possible (this seems to rule out Nomachine NX, and I don't like closed source).

I am on a private network, so I guess I'll probably end up going with XDMCP, but it would seem kinda sorry if there aren't any secure open-source alternatives.

Answer 1

Why not use ssh -X ? You could auto-logon locally with a general user and then autorun a script displaying a form for entering user/passwd which connects to a session using ssh -X...

Answer 2

This seems like a question for serverfault, but couldn't you just setup a VPN between the client computer and the server? That way, all traffic will be encrypted between the two machines.