THIS, MY FELLOW PS3 OWNERS, IS NOT GOOD
Some people are experiencing some problems when connecting to each other. Either in a Game or using the PS-EYE videochat. I've had NAT-3 and it worked on some games but not very smooth. Especially not if you want to team up with you're mates like on FNF and WNW.
Check your system
First of all you need to check what kind of NAT-type you've got.
*Go to Network Settings
in the XMB
*Select Internet Connection Test
You will see something like that picture up there. If you've got NAT-1 or NAT-2
you're good, don't change anything. If it's NAT-3
you're fucked. Not really because that's what we're here for right? To sort this thing out.
If you don't want to know what NAT is and just want it to work
and don't bother to look at the Wall-o-text�.
If above stated link doesn't get you anywhere you can look at some Router Specific instructions at http://portforward.com/english/routers/port_forwarding/routerindex.htm
*You just have to click on your router
*Now look under 'P'
*Click on 'PS3 NAT Type 3 to 2'
and follow the instructions.
This must get you sorted. Any questions? PM me or put it in the comments.
Now onto the Wall-o-text� What is NAT - and how do I make that work?
Network Address Translation (NAT) is quite tricky to explain. Put simply, it's a method routers use to allow devices (computers) on a network to talk to the Internet, and vice versa. It's impossible for information to be sent from a network onto the Internet directly without some sort of go-between, and the router acts as a go-between in this instance.
A router has two IP addresses, one of which is 'external facing' and is accessible from the Internet. The other is 'internal facing' and is accessible from the network it's connected to. With the way that the TCP/IP protocol works, devices connected to the Internet will have a certain type of IP address and devices connected to a small local network will have a different type of IP address. When packets of information are sent, they contain such information as the originating IP address - i.e. the IP address of whatever device sent the packet, like your PlayStation�2 Network Adaptor or PC. If a device on a network, with a network IP address, sends a packet onto the Internet directly, whichever computer receives the packet will get confused about where it came from. This is because the originating IP address will be a network address, and the computer will be expecting the packet to come from an Internet address.
Due to the possibility of confusion, routers using NAT will change all packets that are intended for the Internet by putting the router's own external IP address on the packet as the originating IP address. This way, whenever a computer receives the packet, it will be able to reply back directly to the router. When the receiving computer replies, the router will recognise that it sent a packet to that computer and then forward it on to the network device that sent the original packet.
To edit your router's NAT settings, most have an internal web-based interface that is used to configure them. In your router's documentation, and manuals, it should tell you exactly how to do this. Usually it's achieved by connecting to your router's IP address through your web browser.
via: Sony Online Manual What is Port Forwarding and how do I make that work?
Port Forwarding is a method also used by routers to allow the Internet to talk to a network. If an Internet computer sends a packet to your router, and there is no previous record of that packet in a router's NAT table, the router will not know where to forward the packet to. This is where Port Forwarding comes in. It allows you to specify that all packets sent to the router on a specific port are forwarded on to a specific computer, regardless of whether or not it's in reply to a previously sent packet.
To edit your router's Port Forwarding settings, most have an internal web-based interface that is used to configure them. In your router's documentation, and manuals, it should tell you exactly how to do this. Usually it's achieved by connecting to your router's IP address through your web browser.
again via: Sony Online Manual Congrats!
You can go online and shoot someone.