How can one tell what's travelling back and forth over one's internet connection?
Couple of specific examples:
A virus is using my computer to assist in a
DDoS attack:
I am receiving streaming audio/video. How can I tell what port the stream is coming in on. My workplace has blocked most streaming media but I am still able to get some from various radio stations but not others. I suspect they are using port blocking of the streaming port (1775???). How can I tell for sure?
A web bug is reporting back to its owner what I'm up to.
Etc.
How can I tell at any given point, what traffic is flowing over my connection (who from, who to, what port, and the amount of data being transmitted - e.g., a trickle or a raging river).
Is there a tool that I can use to help me figure this stuff out??