How Skype Punches Holes in Firewalls

[jason]

Ex-Lemmingworks. ##.

Slashdot | How Skype Punches Holes in Firewalls “Ever wondered, how P2P software like Skype directly exchanges data — despite the fact, that both machines are sitting behind a firewall that only permits outgoing traffic? Read about the hole punching techniques, that make a firewall admin’s nightmares come true.”

I’ve never liked skype, though perhaps it has improved. When I found it was using my computer to route information and was making connections to things over the internet even when I had it turned off and disabled, I wiped the harddrive and did a clean install of everything to be sure it was off my computer. Of course there are people who know more than I do who can run skype and control port access and whatnot. But for the rest of you, when there’s something bad on your computer that runs when you tell it to turn itself off… what else is it doing or can it do?