"It is important that you have a decent Internet connection
because your client computers will fetch all needed packages from
the repositories in the Internet (I tested this on a 30MBit
connection which seems to be fast enough. ;-)). It is possible to
store all packages on the PXE server as well so that you don't need
an Internet connection (just the LAN connection to the PXE server),
but then you need a lot of storage space on the PXE server
(remember, it will serve multiple distributions), so I don't cover
this here.
"And the most important thing is that your client computers
support booting over the network. You should check each computer's
BIOS for this option.
"On our system that should serve as the PXE server you should
have already set up a basic Debian Lenny server system, for example
as shown in the chapters 1 - -7 of this tutorial:
http://www.howtoforge.com/perfect-server-debian-lenny-ispconfig2"