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New Member

question about nat pools

Hi all, Can anyone tell me why they would use a nat pool, why not use static nat or pat, If using dymamic, wont the source address be different each time you initiate an outbound session, how long is the binding on such pool, and when would we use them ?

New Member

Re: question about nat pools


static nat requires one to one mapping,so it does not conserves real IP addressess. Usualy is used only for public servers which requires visibility form the outside world.

Dynamic nat assures more flexibility,enables address reuse, and requires less administration work.

In some cases like overlaped networks or TCP load distribution dynamic pools must be used.

In real world scenarios in most of the cases a mixture of static and dynamic nat is used.

The source address will be different only if all the previous connections are terminated with the specific nated Ip and/or the binding timeout is reached, and the address is returned to the pool for reuse. This timeout value is dependent by the protocol type (default values tcp=24 hours, udp=5 minutes, dns=1 minute etc.) and is configurable.

Hope this helps