Hey Lion Face, I cant find any DMZ zone settings on my modem....i;ve confirmed its the Thomson Speedtouch st516....confused even more now.
One thing to note is when I initially set everything up through my dlink router, i had to specify Dynamic IP (DHCP) within the dlink interface for the internet connection. I tired pppoe etc but then I get no outside internet connection. ARRGH!
I just looked up your modem manual, its confusing because they call it a 'Public IP' and its under the instruction part of the manual for 'Assign Public IP' Chapter 4.6.3, Page 71. Follow those instructions on that page, and it should setup a DMZ for your Router. The IP Address you want to put in here will be 192.168.1.20 provided you follow the rest of my instructions.
These instructions assume you have a the default settings for your Modem (which to access the settings would be 192.168.1.254) and your router (to access the settings would be 192.168.0.1)
On your router side of things.
Manual Configuration
Select Internet Setup
In the drop down box for 'Internet Connection Type' - Select 'Static IP'
Put the following numbers in the boxes..
IP Address: 192.168.1.20
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.1.254
Primary DNS: 192.168.1.254
Everything else should be just default settings.
Save and Reboot Router, make sure you can connect to the net with these settings in place.
For your PS3 your Manual settings should be
IP Address: 192.168.0.20
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.0.1
Primary DNS: 192.168.0.1
Save and Test Connection, you should be able to connect to the net with these settings.
Back in your Dlink Router settings, you have to put the PS3 IP Address in the DMZ. You will find the DMZ settings under 'Advanced' then 'Firewall Settings'.
Near the bottom of the page you will see 'DMZ Host' You want to tick the box to enable DMZ and then put in your PS3 IP address, which if you followed my instructions will be 192.168.0.20. Save settings and reboot router.
Now provided you have followed my instructions in setting up a static IP for both your Router and your PS3 and putting the IP addresses into the DMZs of the Modem and the Router, you should be able to do a Net connection test on your PS3 and have it come up NAT2, all going to plan of course
As for the rest of this thread. My experience with Modems over the years, I have found a few things.
-Modems from ISP's have often been flashed with custom firmware unique to the ISP, and are often quite limited and can't perform normal tasks that a store bought modem can. Often you can find the Make and model of the modem and flash original firmware onto the modem, but you do so at your own risk as you can quickly turn your modem into a brick if everything isn't compatible. If you find your modem, no matter what you do won't allow NAT2, its probably a firmware issue, and unless your keen to mess around with firmware, your probably best and easiest to pick up a new modem. My very first free modem from my ISP had all the DMZ and Port Forwarding features, and would accept the settings for them, but it wouldn't actually put them into practice, I tried flashing the firmware with the manufacturer firmware but ended up bricking my modem and buying a new one, one of the best things I had done and taught me a lot.
-Modems and Modem/Routers often have a life span of about 2 years of constantly being on. There is no real obvious sign that they are at the end of their life. The most common one is having speed issues and connection issues. They require a reboot often and never seem to perform as they had in the past, even with factory resets to them. Its an average, but, from my experience, has been consistently about 2 years from the date of purchase that the modem starts to go on the fritz and its time to buy a new one.
As for GT5Prologue....
The problem, I think, with GT5P, is since they have allowed for Host Migration, the game has become a lot more finicky about connections, and I think all players must have a good NAT2 connection to get through without trouble. But even then, if you throw a NAT3 connection into the mix and that NAT3 connection gets connected, it can cause issues for other NAT2 players. Hence the abundance of FTC's since the change. Thats just my best guess at it, as its a change by Sony/PD side of things, not the consumer side.