You can sniff what it's sending with Wireshark, but I'd be surprised if someone hadn't already investigated it for you. Quick googling only found this; they don't know what it's sending back to the mothership, but think you can prevent it from sending whatever it is without preventing it from doing its smoke alarm thing.
Right. So this is advantageous because (A) I'm about to have a Windows machine up and functional for the first time in decades (B) The whole damn internet will be coming through this thing. Is there a clever way to get it to report to me what it's seeing from assorted internal IPs? 'cuz I discovered today that my friendly neighborhood smoke detector will gladly tell me over the internet how many times my toddler got up to pee last Wednesday night.
You can filter what it displays, including by source and destination. You can (and should!) also filter what it captures in the first place.
Some of the DD-WRT firmwares, Tomato etc have the ability to sniff everything crossing your network. I've played with them when I had roommates to keep them from downloading virus and illegal music programs. You can also play with DD-WRT and use it like a full commercial firewall and block adds at the network entry point. Mince will even block all Java applets if I am feeling extra paranoid. Link Only thing to be wary of is that you have to match the firmware of your router EXACTLY with the exact software loads.