technical meaning of strict/moderate nat

[charliehxbox]

Could someone point me to a technical definition of xbox's "strict nat" and "moderate nat", in terms that would help a networking engineer to understand and analyze the issue in technical terms?

[jimmy_Bish]

This is probably one of the most basic principals a networking engineer would deal with. Port forwarding.

Well NAT is Network Address Translation. The process of allowing numerous private IP addresses to talk to each other and also communicate with the internet through a single IP address provided by your ISP.

As far as NAT on a 360 is concerned, the 360 tries to communicate with the Live servers through specific ports, and then the Live servers try to communicate back.
If the 360 can talk outward but the Live servers can't talk back then you have a strict NAT. The way to solve this is the forward the appropriate ports to the IP address of the 360.
This means that Live can send the information to your ISP-provided external IP address. Your router gets this information, looks at the data and which ports the data is trying to come in on. The router then compares the ports in the data to the port forwarding rules you have entered, so it knows to forward all data specific to those ports to an internal IP address, which would be your 360.

Without the ports being forwarded the router has no idea what to do with the data. By default, the data usually gets blocked.

[charliehxbox]

Thanks.

It's actually a bit more than that. I found the definitions I was looking for in this document starting on page 7:

download.microsoft.com/download/5/b/5/5b5bec17-ea71-4653-9539-204a672f11cf/Xbox-Live.doc