Intended for a desktop environment

Even there were no danger to the machines from the problem with two power supplies, there still wouldn’t be any way to get the two PCs talking to each other, since USB doesn’t support that particular kind of communication. If you need to use nothing but USB, consider using USB based Ethernet adapters to hook the PCs together. If you’re familiar with transmission line theory and want more detail on this topic, take a look at the USB signals section of the developers FAQ. This method has a number of usb cd writers advantages and, since USB is intended for a desktop environment, the range limitations were deemed acceptable. When USB was designed, a decision was made to handle the propagation of electromagnetic fields on USB data lines in a way that limited the maximum length of a USB cable to something in the range of 4m.