How to get an Open NAT on Xbox Live While Keeping Your Network Secure

Update: I have posted an improved, easier to both follow and complete set of instructions for getting an Open NAT on Xbox Live here http://xblconnect.blogspot.com/2010/03/getting-open-nat-for-xbox-live-with.html

1. Go to my xbox
2. Go to system settings3. Go to network settings
4. Go to configure network
5. Under ip settings it says the systems ip address. You need to remember it. You should keep this screen up.
6. Log into the router. To do so enter one of the following ip addresses into your computers browser. 192.168.1.1 (Netgear), 192.168.2.1 Note: these are not the ip adresses routers use so if your can't access your router with one off these you should enter the Xbox's default gateway which should be be on the screen you found the xbox's ip address on, which you should have left up.
7. Log into your router with your username and password. The default password for routers varies. There could be no default username and password and both could be left blank. The default username could be admin and the password could be left blank. If these do not work search for your routers default username and password on a search engine. You could have changed your routers username and / or password to something else and if you did so enter that.
8. Assign your Xbox 360 the IP address it currently has. The Xbox's IP address is on the screen you should have left up. Assigning an IP address to your Xbox 360 various on the router you have. For Netgear routers it should be under lan IP setup.
9. Enter your xbox 360 as a dmz server by entering the IP address you assigned your xbox 360 into the dmz server line on your router. For Netgear routers the dmz server line should be under WAN setup.
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This should give your Xbox 360 an open NAT, which it should have to connect to Xbox Live with. This allows you to give your Xbox 360 an open NAT while keeping your computers still protected by a firewall.