Verizon FiOS → Actiontec MI424WR Firewall Settings

I posted this question yesterday in the Fios Internet forum but no one has responded.
»forums.verizon.com/t5/Fi ··· Internet
Can someone please explain to me the difference between the Medium and Low settings. I know the Low setting is supposed to accept in inbound and outbound traffic.

When I tested the firewall at GRC.com with the Medium and Low settings and my Windows 7 firewall turned off both pass the Shields Up test showing no open ports.

Since the Low setting accepts inbound connection I would of thought there would of been some open ports. Also since Low passed the Shield Up test is there any reason to use the medium setting?

Also I have read the user manaul and it did not answer my question adequately.

Thanks.

No one here has any ideas or thought on the firewall settings?

Are you actually running server software that is listening for connections such as a FTP, Telnet or Web server? I'm also thinking that as long as you are using NAT and did not initiate an outbound connection, the router will still throw away unsolicited incoming messages on the WAN. What exactly is the reason why you want to mess with that setting?

No reason really. I was just surprise that the firewall set to low was able to still pass the Shield Up test.