"Reverse" firewall testing?
April 10, 2008 8:30 PM Subscribe
Simply put, I would like to determine which (outgoing) ports are open and which are closed on my company's network. They have a firewall blocking most ports...so far I can only get through port 80 and port 443. I know for example, ports 23, 25, 110 and 6667 are blocked. So I may be over-thinking this, but what I think I need to do is find a way to listen on all ports (or at least a select list) on an external computer, then scan that computer's IP from inside the network to see what connects... The catch: I would like to open these ports for connections without having to install servers that actually use those ports. If we're talking a couple hundred ports, I don't want to install and configure a couple hundred server apps. (or all 65535?) Does anyone know of an app that will open 'fake' ports on a system and respond with some sort of generic server type? I know I've seen such an app before, but I just don't remember what it was called, and my google skillz are not coming through this time. Side note: I originally thought what I was looking for was a "leak tester" ...but this isn't quite right, as it is testing incoming ports, not outgoing ports. Thanks,