Windows Terminal Services is a new concept for many system administrators who expect systems to be essentially single user. It brings true multiuser capability to Windows. UNIX systems have traditionally been primarily multiuser, with a single large server that serves many terminals.
Each user who connects to a Windows 2000 server using Windows Terminal Services (or Remote Desktop in Windows XP) is actually using the resources of the server itself, not the particular workstation at which he or she is seated. The user doesn't depend on the speed of the workstation, but rather is actually sharing the processor, RAM, and hard disks of the server itself.
Each user gets his or her own Windows Terminal Services session, and each session is completely isolated from other sessions on the same server. An errant program in one session can cause that session's user to have a problem, but other users are unaffected.
Each user who connects to a Windows 2000 server using Windows Terminal Services is actually functioning as a terminal on that server. Windows Terminal Services supports a wide variety of machines as terminals—from diskless display stations running Microsoft Windows CE entirely in memory, to Microsoft Windows 95/98 workstations, to Windows 2000 servers. The terminal is responsible solely for the console functions: that is, the keyboard, the mouse, and the actual display. All else resides on and is part of the server.
The Windows XP Professional Remote Desktop feature is identical to the Windows 2000 Terminal Services client. However, it's installed by default, can be used like the Windows 2000 Terminal Services Remote Administration mode, and is configured slightly differently.
Terminal Services provides an ideal solution for the mobile user who needs to be able to run network-intensive or processor-intensive applications even over a dial-up connection. Because the local machine is responsible only for the actual console, the responsiveness and bandwidth requirements are substantially better compared to trying to run applications across a dial-up line.
Because all applications in a Windows Terminal Services session are running on the server, management of sessions and applications is greatly simplified. Any changes to applications or settings need only be made once, on the server, and these changes are seen by all Windows Terminal Services sessions.
In addition, Windows Terminal Services allows an administrator to view what is happening in a user's session, or even to directly control it. Help desk personnel can actually see exactly what the user is seeing without leaving their desks. If the user is configured accordingly, the help desk person can share control of the session, walking the user through a difficult problem.
When configured in remote administration mode, Windows Terminal Services can also be used as a management tool. When enabled in this mode, administrators can log on directly to the machine from their desktops to perform normal system maintenance without having to sit at the server console. This is a powerful addition to the administrator's repertoire, enabling direct control of all servers without leaving the desktop. Every system administrator will probably enable the remote administration mode of all of their servers. The overhead on the server is minimal compared to the benefits.