I have to echo what Sandeep and most are saying on the thread. For me, no matter how fast your connection, I do not see why you are trying to use AC over the connection. You are sending all of the data from your host server to your remote client. This is why it times out. Think of a web page that loads slowly and then multiply by a bunch. Sandeep has given you the numbers.
In order to be more helpful, we need to know what the OS are. Are you connecting to a server, etc.?
I don't see any advantage of using the AC app on the desktop and connecting via the VPN vs just using RDP, LogMeIn or GoToMyPC. It is simply much faster.
The only downside to RDP if you are not using Windows Server 2008 is that it must use port 3389. This is a very non-secure port. However, this port number can be changed.
But, unless you have RWW or Windows 2008, I would highly recommend the parent software, LogMeIn.
