what is an average number of users to be found on the network?

as i understand it, the protocol used by limewiree is open source, ( and is used by other clients, morpheos etc ) why then does my friend who uses something called kaza or something say he is on a much bigger network? i thought all clients are on the same network?

One source for network size is available at Limewire.com look on the left hand menu under Gnutella / Network Size. Limewire is but one of many clients using the Gutella network which by all accounts I have seen is the largest with Kazaa coming in second. The Gnutella network distinguishes itself by it's own protocols using a specific port... but in reality it is all traveling on the public internet. It becomes what you might call a 'virtual private network' as when you are using a Gnutella client it only listens and talks to other Gnutella hosts. Think of the network as a large room and individual protocols being specific languages... we all hear one another but we only pay attention to those speaking our primary language (English, Spanish, French, German etc.) thus we all share a common space (The Internet) but we are only ocncerned with traffic (Language) that we are interested in.

In this way Gnutella clients only work with one another and Kazaa clients only work with their network and so on.