tcpdump takes temporary access of network devices to dump network packets on a terminal screen
if you’re using a Mac, fire up the console, and type in: sudo tcpdump -a (be sure to read the man pages, I still have to read)
it’ll show you who’s connecting to your network, and what networks your connecting to.
this is an invaluable resource for network administrators, if only routers supported a java applet that just dumps tcpdump data
also be sure to save your files in hexadecimal file format, ie 0xffffff.txt