is a free and open source terminal server for Linux that allows many people to simultaneously use the same computer. Applications run on the server with a terminal known as a thin client (also known as an X terminal) handling input and output. Generally, terminals are low-powered, lack a hard disk and are quieter than desktop computers because they do not have any moving parts.
This technology is becoming popular in schools as it allows the school to provide pupils access to computers without purchasing or upgrading expensive desktop machines. If the school does not have enough computers, new thin client machines are less costly than standard computers. If the school does have enough computers but they are a few years old, they may be able to extend the useful life of obsolescent computers by converting them into thin clients, since even a relatively slow CPU can deliver excellent performance as a thin client. In addition to the possibility of getting more performance for less money by getting one high-end server and turning their existing computers into thin clients, an educational institution may also gain more control over how their students are using computing resources by switching to a thin client configuration.
Some examples of distributions using LTSP are Edubuntu, K12LTSP and Skolelinux. LTSP is a registered trademark of DisklessWorkstations.com, LLC.
The founder and project leader of LTSP is Jim McQuillan.
The LTSP client boot process
On the LTSP server a chroot environment is set up with a minimal Linux operating system and X environment.
When a client (any networked computer capable of running Linux) boots from a local boot device (like a harddisk, CD-ROM or USB disk), it loads a small Linux kernel from that device which initializes the system and all of the peripherals that it recognizes. When configured fornetwork booting (with mechanisms like Preboot Execution Environment (PXE) or NetBoot), the client first requests its own IP address and the IP address for the LTSP server via DHCP and loads the Linux kernel from a preconfigured Linux image on the LTSP server via the Trivial File Transfer Protocol (TFTP) service running on the LTSP server.
During this process the client makes a (new) DHCP request for the IP address of the LTSP server and the path to its chroot environment. When this information is retrieved, the client mounts the path on its root filesystem via either the Network File System (NFS) or Network Block Device (NBD) services running on the LTSP server.
The client loads Linux from the NFS mounted root filesystem (or NBD filesystem image) and starts the X windowing system. The client connects to the XDMCP login manager on the LTSP server. From this point forward, all programs are started on the LTSP server, but displayed and operated from the client.
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