Question : How do I find whether a bittorrent (protocol), application is running on a computer

I need to know which computer has a program installed and using BitTorrent protocol.

How do I do that?

Answer : How do I find whether a bittorrent (protocol), application is running on a computer

Wireshark will work.  Install it on a computer and place in promiscuous mode so it listens to all traffic and not just your computer's traffic.  It's a safe application that's been around for a while and is highly supported.  Here is a website that walks you through configuring wireshark to sniff the network for bittorrent traffic: http://wiki.wireshark.org/BitTorrent