Are you connecting to a server (NT4TSE, Windows 2000 Server, Windows
Server 2003) or a client OS (WinXP, Vista)?

To get to my home PC from wherever I am I use ssh to first connect to
my Linux machine at home. I use port forwarding to connect to my
Windows machine from there. (ssh -L 3390:windowsbox:3389
username at ssh.host.com, point the Remote Desktop Connection client to
localhost:3390). I've enabled SSH keep alive in my sshd_config file,
and my connection can be stable for days.

I'm not sure if this works on WinXP as well, but in Windows 2000 and
2003 you can set some keep alive options via group policy. Computer
Configuration > Windows Components > Terminal Services. The keep alive
features are rather different from those offered by SSH however and
may not make any great improvements.

RDP isn't the most secure protocol in the world, better than VNC but
still not overly strong. Your best bet would be be to use RDP via a
VPN or SSH.

-- 
Andrew S. Zbikowski | http://andy.zibnet.us
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