What is Remote Desktop?
Remote Desktop allows the graphical interface of a remote Windows system to be displayed over a network onto a local system. In addition, keyboard and mouse events on the local system are transmitted to the remote system enabling the local user to perform tasks on the remote system as if they were physically sitting at the remote system. Conversely, resources (such as printers and disk drives) on the local system can be made available to the remote system for the duration of the connection. This remote control can be established in a number of ways, including over wide area networks (WAN), local area networks (LAN) or over the internet.
In the case of Windows Server 2008, this service is provided by Terminal Services running on the remote systems and the Remote Desktop Connection (RDC) client on the local system.
Terminal Services run in two different modes, Administration and Virtual Session. Remote Desktop for Administration provides full administration functionality to the remote administrator (including access to the console session and visibility of notification messages). Remote Desktop for Administration is the equivalent to working directly at the remote system's console. In virtual session mode the user is subject to some limitations such as the ability to install applications and view console notification messages.
Windows Server 2008 imposes some administrator logon restrictions. Specifically, a maximum of two administrators may be logged on at any one time, either two logged on remotely, or one local and one remote administrator. This assumes, however, that different accounts are being used to log on. In other words, the same user may not log on locally and remotely simultaneously.