Connecting workstations w/o hardisk to a

1. Is it possible for a workstation that has no hard disk to boot from lan and connect to server that is running under OS(Windows 2000 prof/Windows 2000 Advance Server) w/o using a dos boot floppy? If YES, what are that software and hardware that isneeded to achieve this setup.
2. Is it possible for the workstation run on a different OS like windows98?

4. what is ‘boot ROM’

3. Is it required for all workstation and the server to have both a network card with ‘boot ROM’

Can anyone here give me a detailed information on how to do this. I will highly appreciate your help. You can email your answer to derflanoj@yahoo.com if necessary. thanks a lot.