I have a Windows 2008 R2 Server with RDP access enabled. However I'm not limited access by IP.
Why..
I'm a 2 person company so all server issues I have to care of.
Last weekend I was out hiking and I got call from a client that their site was down. Using an iPhone (with the RDP client app) I was able to connect to the server recycle the IIS app pool and save the day from all from the top of a mountain.
However this is not very secure. I need to limit RDP access by IP address. However the iPhone does not have a static address, it changes all the time. The only thing static about it is that the host name always contains ".mycingular.net"
Is there anyway I can limit RDP access by hostnames (with wildcards, e.g." *.mycingular.net)
I believe the answer is no, there is no way to do this using what is built-in to windows. You could setup a VPN between the iPhone and your network.
http://support.apple.com/kb/ht1424