as Console Servers usually have highly advanced security functionality to ensure that only qualified personnel can access various servers and that any data that is transmitted across the LAN, or over the Internet, is encrypted. Marketing a product as a console server is very application specific because it really refers to what the user wants to do—remotely control, monitor, diagnose and troubleshoot equipment over a network or the Internet. Some users have created their own console servers using off-the-shelf commodity computer hardware, usually with multiport serial cards typically running a slimmed-down Unix-like operating system such as Linux. Such "home-grown" console servers can be less expensive, especially if built from components that have been retired in upgrades and allow greater flexibility by putting full control of the software driving the device in the hands of the administrator. This includes full access to and configurability of a wide array of security protocols and encryption standards, making it possible to create a console server that is more secure. However, this solution may have a higher TCO, less reliability and higher rack-space requirements, since most industrial console servers have the physical dimension of one rack unit (1U), whereas a desktop computer with full-size PCI cards requires at least 3U, making the home-grown solution more costly in the case of a co-located infrastructure. An alternative approach to a console server used in some cluster setups is to null-modem wire and daisy-chain consoles to otherwise unused serial ports on nodes with some other primary function. See also Conserver KVM switch Linux Terminal Server Project Modem sharing device P4000 Time-sharing References External links Tom Fine: Console Server How to build your own console server using FreeBSD Remote Serial Console HOWTO Linux Serial Consoles for Servers and Clusters By Matthew Hoskins 2004 Project Hydra: the USB Multiheaded Monster by Poul Petersen 2004 Telecommunications equipment System administration Out-of-band management Server Networking hardware Telnet