Network Booting varies from platform to platform and application to
application. For PC hardware, PXE (Preboot Execution Environment) is
the standard. Most enterprise level networks cards support it, but it
may be disabled by default. For PXE to work, you define information
such as the tftp server and network bootstrap image to load into
memory. The PXE client downloads the network bootstarp image, and then
PXE hands over control of the hardware to the network bootstap image.

The computer boots the network bootstrap image. The bootstrap image is
a small image, usually it only has enough of the operating system to
boot the computer, start up the network, and mount a network
filesystem or start a Citrix, Windows Terminal Services, or X11
session. For more advanced environments, the bootstrap image would
mount a remote file system and run the operating system from an image
on the remote server. Mac and Sun computers for example can do this as
out of the box as long as there is a working netboot.

I use network booting for installing/reinstalling operating systems on
hardware. I am currently using Microsoft Remote Installation Services
(RIS) to deploy/reinstall WindowsXP. I also have hacked the Ubuntu
netboot, Offline NT Password & Registry Editor
(http://home.eunet.no/pnordahl/ntpasswd/), Ghost Console Client boot
disk, and I almost had Knoppix working but I abandoned Knoppix due to
time constraints. Unattended (http://unattended.sourceforge.net) is a
project for setting up a RIS like system on a Linux server. You can
also just look for instructions on how to setup PXE booting hosted by
a Linux server.

Another Microsoft Example: Microsoft's Windows Distribution System
(WDS, Server 2003 and 2008 replacement for RIS) boots the WindowsPE
operating system on the client in order to copy a WDS image to the
local storage. WDS is intended to deploy Windows Vista and Server
2008, but it has backwards compatibility with RIS. I haven't gotten a
working WDS environment going yet. Vista and server 2008 deployments
aren't high on my priority list. ;-)

The Linux Terminal Server Project (http://www.ltsp.org/) is a thin
client solution for Linux. With LTSP you can turn your existing PC
hardware into a diskless system that connects to a Linux server via
XDMCP.

-- 
Andrew S. Zbikowski | http://andy.zibnet.us
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