In my business I have a windows network connected to the internet through a router. Recently we had a virus on one of the PCs that sent spam. Our ISP almost cancelled our account, but they were able to help us isolate the computer. Now, I'd like to set up a computer (probably a linux box) to act as a go between the network and internet so that I could log all traffic going in and out. Our router has a log function, but it seems to fill up to quickly. How would I do this?