Nat & pat

surfthegecko

Hi,

Just after simple clarification really.

Is NAT the translation of 1 inside (private) IP to 1 outside (public) IP.
Is PAT the translation of Many inside IP's to 1 outside IP, using Port Numbers.

Thanks
Nick

jscimeca715

surfthegecko wrote: »

Hi,

Just after simple clarification really.

Is NAT the translation of 1 inside (private) IP to 1 outside (public) IP.
Is PAT the translation of Many inside IP's to 1 outside IP, using Port Numbers.

Thanks
Nick

NAT and PAT both translate many inside to one outside IP's. The difference between the two is rather small, with PAT also translating the port numbers like you said. Matter of fact, the Wendell Odom book says that NAT is just a more popular term used to describe both.

Neeko

If you need to differentiate between the two, PAT is simply NAT with the use of port numbers which as you have said allows a many private addresses to one public address arrangement. PAT can be used for other arrangements though, for example inbound one to one translation for for a particular service (RDP, web servers etc)

From my experience most people just use the term NAT to refer to any form of address translation.

surfthegecko

thanks guys. As long as im on the right track.

Im sure if I delve deeper there will be some underlying differences, but as long as I have the main concept thats cool.