On Apr 20, 2010, at 12:55 PM, Joe Abley wrote: > > On 2010-04-20, at 15:31, Roger Marquis wrote: > >> If this were really an issue I'd expect my nieces and nephews, all of whom >> are big >> game players, would have mentioned it. They haven't though, despite being >> behind >> cheap NATing CPE from D-Link and Netgear. > > I have heard it said before that there is significant cooperation and/or > software engineering work between some or all of those who make residential > gateways and those who make multi-player games to achieve this end result. > The opinion I heard vocalised at the time was that it would have been a lot > easier to reach this state of affairs if there had been standardisation of > NAT in v4 at an early stage. As it is, peer-to-peer apps like games require > significant if-then-else to make anything work. > The fact that they work is usually due to uPNP or another inbound NAT-T solution. All of these will be very unlikely to work in an LSN environment. None of them work in a multilayer NAT environment.
>> Address conservation aside, the main selling point of NAT is its filtering >> of inbound >> session requests. > > If that was all that was required, you could sell a stateful firewall that > didn't do NAT, and everybody would buy that instead because it would make > things like iChat AV break less. Apparently there are other reasons to buy > and sell devices that NAT (e.g. my ISP gives me one address, but the laptop > and the Wii both want to use the internet). > In IPv4, yes, there are other reasons. (Address conservation). In IPv6, it shouldn't be a problem to sell a stateful firewall that doesn't do NAT. Owen
