You can install Windows 2000 Server Terminal Services in either of two modes: Remote Administration or Application Server. Remote Administration mode installs only the remote access components of Terminal Services and performs with very little overhead, so it's ideal for mission-critical servers. Terminal Services in Remote Administration mode permits a maximum of two concurrent remote administration connections. No additional licensing is required for those two connections, and you don't need to run the Terminal Services license server.
Application Server mode installs the application-sharing components of Terminal Services in addition to the remote access components. This mode lets users run applications remotely. However, running Terminal Services in Application Server mode requires you to purchase licenses and set up a Terminal Services licensing server within 90 days of installation. For administration purposes, you should install Terminal Services in Remote Administration mode. Remote Administration mode minimizes the impact on server performance while still facilitating remote administration.