Another new feature of Windows Server 2008 is Terminal Services Gateway (or TS Gateway), which is designed to provide authorized users with secure, encrypted access over the Internet to terminal servers on your internal corpnet. In other words, a salesperson arriving at a hotel in Hong Kong could open his Windows Vista laptop to bring it out of sleep mode, connect to the Internet using a hot spot in the lobby, and launch a RemoteApp program on his machine that actually runs far away on a Terminal Server hidden behind your company's perimeter firewall at headquarters in New York. Or, depending on how your administrator has defined its resource authorization policies, the user might be able to access the remote desktop of his own desktop computer in New York, provided Remote Desktop has been enabled on it. And if the remote user is an administrator, he could access the remote desktop of any servers within his internal corpnet (provided Remote Desktop is enabled on them) and securely manage those servers and do whatever tasks he needs to perform on them.
And you can do all this without having to use a virtual private network (VPN) connection. Plus this will work regardless of the type of perimeter firewall your company has set up, or even if your business is using Network Address Translation (NAT). All it takes to make all this work is that your perimeter firewall has to allow TCP port 443 so that HTTP SSL traffic can pass through from the outside.
To learn more and to read the entire article at its source, please refer to the following page, Computer Techno: Windows Server 2008 Terminal Services Gateway