LTSP
Light Terminal Server Protocol is a method for using PXE (Portable eXecution Environment) to provide thin-client boots over a network. This facility is useful for hardware testing and potentially for the Inventory tracking database.
How it works[edit]
PXE or "netboot" is a facility that allows client computers to request a boot image from a local server on startup. It requires that the client network device support the facility, meaning that it needs to have an "Option ROM" enabled. Most but not all network devices support this. If the Option ROM is available, it must be enabled by the BIOS.
When the client boots in PXE mode, it sends a DHCPRequest with certain options. The local server needs a version of dhcpd which supports these options; for example, dnsmasq does not (as of 2011, last time I looked.)
The server responds to the DHCPRequest with the usual information (address, netmask, default gateway, etc) along with the address of a tftp (Tiny File Transfer Protocol, a subset of regular FTP) server. The tftp server provides boot images. In the case of LTSP, the boot images are Thin Client images.
A thin client is a tiny operating system which contains a display server and little else. The thin client typically connects to an application server after booting and runs applications remotely, showing their output on the local display. This is somewhat like running
ssh -X
on a normal computer.