Which kind of DVI cable to use with a KVM switch?

Hi. I have a Power Macintosh G5 and three (3) Mac Minis. I also have a Apple Cinema Display (DVI). I recently purchased a Avocent 4 Port DVI/USB KVM switch. I just got it today. It looks like a nice switch. However, it did not come with any cables. So, I need to buy some USB cables and some DVI cables. Should I buy DVI-A, DVI-D, or "dual" DVI cables?

Thanks in advance for help.