--the router light refects all the connection traffic. See the LimeWire tools->statistics->bandwidth to watch how much data is being processed. The "gnutella" traffic is for searches and connections; the "http" traffic is for transfers.

If you are running as an ultrapeer, that will use up about 10 KB/s alone.

re the search recognition, LW makes a table of file descriptions that uses keywords from the filename, folder path/names, metadata (like artist, bitrate etc), time, hash, extension and probably even more data that accurately describes a file. It's a bit like the Finder Info, but much fuller.

So, when enough of the keywords match the table, LW will respond to a search request.

If you are interesting in searching for even more info about the ideas behind much of gnutella's code, the developers have started and are updating a searchable wiki. Here's the link http://www.the-gdf.org/wiki/index.php?title=Main_Page

cheers