You computer apparently does not have a firewire port.If the Sony camcorder uses miniDV tapes, it needs a firewire cable to connect to the firewire port of your computer. Firewire and USB are different. If your computer does not have a firewire 400 port, you can add one.Firewire, IEEE1394a and i.Link are all the same thing.Not all traditional Windows computers have firewire ports. All Macs (with the exception of the new Mac Air) have had firewire ports for many years.