5.1.4 Terminal Server Role
The Terminal Services Role provides remote access to a server through terminal emulation software, which
sends keystrokes and mouse movements to the server and allows clients to execute applications, process
data, and store data on the server. Thereafter the Terminal server returns the display to the client. The
terminal emulation software can run on a number of client hardware devices, such as a personal computer, a
Handheld PC (H/PC), or a terminal. This also allows remote control of servers and centralized application
management, and minimizes the network requirements between the server and client.
The Terminal Services Role involves the creation of several components that works together. These
components include a presentation layer protocol called the Remote Desktop Protocol (RDP) and a core
architectural component called the Multi-Win.
The Multi-Win component enables more than one user to be logged in locally. It is a core component of
Terminal Services and is used in Remote Desktop for Administration, Remote Assistance, and the terminal
server role. The creation of Multi-Win enabled remote users to log on and use the server as if they were
local users. The Multi-Win component also keeps each userís system and application settings separate, even
when many are logged on concurrently. This enables remote users to launch and use applications on the
remote system. When you establish a terminal server session, by default you see a copy of the desktop from
the server to which you have connected. When you double-click an icon within this session and launch an
application, it launches in your session on the server. It uses the serverís processor, the serverís memory,
and accesses the serverís hard disk. Only images of the screen transfer to the local computer; the application
files never leave the server.
Note: Each client computer that accesses Terminal server that is used in
terminal server role must have the Terminal Services Client Access
License as well as the Windows 2003 Client Access License. You are,
however, allowed to run Terminal Services in terminal server role for 120
days without using any license. Thereafter the service will fail.
The Remote Desktop Protocol (RDP) is responsible for transferring the screen information from the server
to the client and the cursor movements and keystrokes from the client to the client session on the server.
Windows XP and Windows Server 2003 use RDP version 5.1, while Windows 2000 uses RDP v5.0 and
Windows NT 4.0 uses RDP v4.0.
RDP uses encryption to protect the information that is sent between the terminal server and the client
computer and uses port 3389 to transfer this information.