Thanbks to F-ZeroX for this helped me and hope it helps you

Since i have had COD:WAW, i have had many online/connection issues which really annoyed me:(. I didnt understand why: i had a new ps3 and a fine internet service (Virgin Media). I couldn't join specific lobbies hosted by certain people, speak through headset, be invited or invite friends to games (it always said "games session has ended"), taking ages to join games and sometimes being signed out for no reason. I realised that this was mainly because the UPNP was not avaliable and i always had NAT type 3.It all changed when i discovered the DMZ...

1) Putting my ps3 into the DMZ of my router solved all the problems and many more: i noticed that i became the host of games more often (which solved the problem of "host has ended the game" or "game ended because poor connection to host" because u r the host) and that 90% of the time i had UPNP available and NAT type 2!!. So i strongly advise people who have experienced online problems to do so- i guarantee you will benefit from it some way. i know JimGill has mentioned it but i will tell you how to do it using these simple steps:

1) First you need to find your routers "default gateway". On your computer go to "run" in the start menu and type in "cmd". Type in "ipconfig" and look for "default gateway". Note down the numbers.

2) Now go on ur ps3, go to Settings > Network Settings > Internet Connection Settings" option on the PS3 Cross bar menus. Select "Wired" or wireless" (choose the one that refers to you).Both selections should show a page called "Address Settings". Here you will need to select "Custom". Another page will then display entitled "IP Address Setting". The option "Manual" will need to be selected. Now a page of customizable ip addresses can be entered.This is the important part...

Ip address - This will need the static ip internal address:eek:Dont worry lol u dont need to understand. Just enter something like 192.168.1.100 as it is unlikely 99 other devices are connected to the same system. (By the way u can just use 192.168.1.100 for the static ip if u want...it really doesn't matter!!)

Subnet Mask - Is always set to 255.255.255.0

Default router - now enter the "default gateway" address you got earlier from your computer

Primary DNS - Same IP Address as "Default Router"

Secondary DNS - Same IP Address as "Default Router"

Select "Enter" and a "MTU" screen should come up (i dont know what the hell MTU is). Just select "automatic" and then select "Do not use proxy" on the next screen.

3) Now go back on your PC, open your web browser and enter that "default gateway" address into the address bar. A login authorization prompt may come up and you will need to enter your username and password (should be somewhere in the user manuel for the router). If your using a linksys router like me leave the username box empty and enter "admin" for the password.

4) A router configuration page should show up showing many settings and options you will have no clue about (note that all router configuration interfaces are different depending on the make of the router, so the settings/preferences will be in different places). All your interested in is finding a setting named as "DMZ" of anything with "DMZ" in it. So search around in all the tabs and settings for the mention of "DMZ" (it might be in your security/firewall settings). One you have found it, there should be an option of enabling it. Do so and then enter the static ip address you gave your ps3 earlier; the example i gave was 192.168.1.100. So enter that and select "apply" or "save changes". Whilst your on there try and find a setting of "UPNP" and make sure thats enabled aswell.

5) Now turn off everything running on your router including the router, computers, ps3 etc This is done so the changes can take place asap. Wait a few minutes and then turn everything back on and the process is complete. You should realise that the light below the DMZ option on the router should have lit up and do an "Internet connection test" on your ps3. You should get UPNP available and NAT type 2!!

Thanks for everyone who has read this and i hope it helps. If you have any questions, please ask below and i will try to answer:)^[/FONT]

Sorry i couldn't give any video tutorials to show how to do it which would have been much better. But here are some links to some videos from other people (not me) who show how to do the steps on computer which may help u (sorry for their bad quality video capturing): [url="http://www.youtube.com/watch?v=p3RfH5naINo"]YouTube - Broadcast Yourself.[/url]
[url="http://www.youtube.com/watch?v=d5urvVIdtyw&feature=related"]YouTube - How to DMZ (open all ports) to a device on a network.[/url]

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2) PORT FORWADING

Ok, i have had many people pming me complaining that putting their ps3 into DMZ hasn't completely solved the problems they were experiencing especially with friend inviting. The only other suggestion i can make is to port forward...All games have their own specific ports that need to be opened on the router. For COD:WAW the ports are as follow: 3478, 3479, 3074, 3075 (UDP), 80, 443, 3074, 5223 (TCP). The ports are different for other games; to find them just google "(the game's title) ports" or just go to: [ Register or Signin to view external links. ] (however i'm not sure all the ports are totally accurate here)
So after you have put ur ps3 into DMZ, go back onto your routers config page (type in the default gateway in the address bar). Look for a setting named "Port Forwarding" or "Port Range Forward". Now just enter the port numbers, for example the first one is 3478.
Just enter 3478 (start) to 3478 (end) Protocol - UDP (enter the static ip address u gave ur ps3 e.g 192.168.1.100) and then click "enable" (you can leave the "application" box empty-its not important)
Now do the rest of the ports and then select "apply" or "save changes". Done. Issues online should be fixed.

This is a video which might help:

[url="http://www.youtube.com/watch?v=GWPUdW1kIJA&feature=related"]YouTube - Port Forwarding For Noobs, Linksys Routers[/url]

3) DISABLE UPNP BOTH ON UR ROUTER AND PS3

OK, THERE IS ONE MORE SUGGESTION I CAN MAKE....DISABLE UPNP ON YOUR PS3 AND ROUTER. AFTER PORT FORWARDING AND DMZ GO THROUGH THE INTERNET SETTINGS AGAIN ON YOUR PS3 BUT AT THE END MAKE SURE YOU DISABLE UPNP. NOW DO THE SAME ON YOUR ROUTER CONFIG PAGE. APPLY AND WAIT. HOPEFULLY PROBLEMS SHOULD BE FIXED. (THIS METHOD ESPECIALLY APPLIES IF YOU HAVE THE WRT54G LINKSYS ROUTER, BUT CAN WORK FOR OTHER ONES).


NOTE: APPARENTLY BT ROUTERS DO NOT WORK WITH PORT FORWADING AND DMZ, AS TOLD TO ME BY MATTO602, BUT I THINK IT DOES BECAUSE ALL ROUTERS USE SIMILAR TECHNOLOGY...SO JUST TRY IT AND EXPLAIN ANY PROBLEMS U ENCOUNTER...


--------------------------------------------------NONE DMZ METHOD-----------------------------------

This may work or not, but try anywayz. Simply go to ur router manufacturers website (e.g. Linksys, Netgear) and download the latest software for your router. This will have updated settings for it, including port opening systems, more DMZ options etc and may therefore solve online issues on the ps3... (thanks to SirDrinxAlot for mentioning this)