Newbie-Modem traffic
 

This is the first time I've tried Gnutella so this Q may be dumb. Why is there so much traffic on my cable /modem even though I'm not DL or UL.

It's really quite simple: Gnutella uses a peer-to-peer architecture, which means that everyone's computer is a server. Each computer is in a sort of internet within the internet, where each person talks to the others by passing messages from computer to computer. The only difference is that every single computer is a server.