>> An other solution about DVD image could be to make a software (running >> on Linux and on Window) >> that can make a DVD image using all the CDs images and a boot file (to >> download on ftp) Jigdo does exactly what you describe. It assembles the DVD or CD images from the files on the mirrors. If you already have the CDs, you can have jigdo scan the contents of the CDs to assemble the DVD images. Jigdo is worth the time to figure out.