Updated: January 21, 2005
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2
A terminal concentrator is a hardware device that consolidates serial access to multiple servers into a single networked device. You can use this device to monitor a large number of servers simultaneously from one location.
Terminal concentrators include many serial ports connected to multiple servers using null modem cables. Typically, you access terminal concentrators over the network through the Telnet protocol. Terminal concentrators provide an interface through which you can remotely view data on multiple servers that use serial ports as their out-of-band connection.
Terminal concentrators can improve your management of servers because they can establish in-band connections to the servers and then perform out-of-band management tasks. In addition, terminal concentrators make it easier to manage servers for the following reasons:
You can use terminal concentrators to manage multiple servers without needing to be within a serial cable's distance to the computer.
Several administrators can simultaneously view the output of different servers.
Using an out-of-band connection, you can use terminal concentrators to monitor servers methodically. You can also manage multiple servers from one location.
Several companies manufacture terminal concentrators; their setup, features, and configuration details vary. When assessing the appropriateness of a particular terminal concentrator, consider the following:
The number of serial ports available.
Built-in Telnet security features, such as passwords.
The number of Ethernet ports available.
Telnet security features are not standard across terminal concentrators. If your device does not include security features, consider using a secondary private management network accessible through a direct-dial remote access connection or a virtual private network (VPN) connection. You can also use a router to secure network traffic going to the terminal concentrator.
For more information, see Checklist: Installing and configuring the router and Checklist: Installing and configuring the remote access server.
Using Telnet over Internet Protocol security (IPSec) can enhance security. See Internet Protocol Security (IPSec) for additional information.
For more information on terminal concentrators, see Configuring terminal concentrators.
For additional information about selecting hardware for Emergency Management Services, see: