Network Address Translation (NAT)
Suppose you want to host an Xbox Live game and youre using a router thats classified as open. Armed with that information and using the chart above, you can be confident that your routers NAT type will not keep your friends (who may also be using routers) from finding your session, hearing your voice, and enjoying a great game.But lets say youre behind a router thats a strict NAT. When you want to host a game, you now have something to consider.
Anyone else whos behind a router that uses a moderate or strict NAT may not be able to connect to your session.Lets look at one final example going the other direction: you joining someone elses game.
Will you be able to participate fully with everyone in the game?
If you have a moderate NAT on your home network, you can get an idea of what may happen by looking at the chart. If the players you want to play with are using strict NATs, you will likely experience problems.
You may not be able to hear them and they may not be able to hear you. You may not be able to see those players at all.Note NATs dont affect lag; this is all about connecting to other players!
What does each NAT type mean?
It doesnt have to anything to do with security. A router performing open NAT is no less secure than a router performing strict NAT. The classification system boils down to something called a port assignment policy.
* Open NAT means that either the port assignment policy is minimal or the router has a fully compliant version of UPnP (Universal Plug and Play) enabled by default.
* Moderate NAT means that the port assignment policy is minimal, but there is address or port filtering taking place.
* Strict NAT means the port assignment policy is aggressive.
