IEEE 1394 (Firewire) Network

I have a firewire network linking two computers between which I do large file transfers. One computer is connected to a Nikon 9000ED film scanner and the other is connected to an Epson Stylus Pro9600 wide format printer. The network is working great, but it seems to be causing communication issues for these devices. For example, I am printing a file, and my scanner isn’t being detected by the other computer. I reset the computer and the printer computer receives a communication error and the print job is just cancelled right in the middle of the job. What could be causing this? Is it something to do with device sharing, or what? Any advice would be very helpful.