I presume your connected to the internet wirelessly? What firewall are you using? Try disabling it.
This might be of some help too:
quote:
Originally posted by http://www.cagewarriors.com/forums/archive/index.php/t-14715.html
NAT is Network Address Translation, it is a technicque used by firewalls to hide your internal IP addressing and restrict visability of what is on your network. It also enables people to use private IP address ranges internally, as obviously there is a gerneral shortage of public IP address ranges
It is unlikely to be causing you any problems.
It's like to be a bandwidth issue, which means either you have somethig that is using up your bandwidth... spyware, trojans' etc. Some form of Peer2Peer..i.e Limewire, Soulseek, etc.
As you 'share' your broadband bandwisth with other people on your circuit, someone else could be using a lot of bandwidth.
If you have a half decent firewall, you should be able to see what traffic is passing through your firewall and work out if it should be there or not.