i mean, i prefer use floppy disk to boot, and configure it to boot the ip address i could specified ...

But it's maybe not possible at all with knoppix !
( with fc or red hat, there is a special cdrom rescue that allows to boot from ftp server : one have just to give ip address and path ... and installation begins. It is not exactly what i want to do with knoppix : i would like to run live-cd, but in the way that i have just explained).

bye