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NAT Source overlaod outside to inside?

we are trying to overload from inside to outside and from outside to inside.

Why i´m not able to add the syntax "overload" in the statement:

ip nat outside source list XX pool yy "overload"

ios c2600-is-mz.121-17.bin

Do you know if there is any explanation why this is not possible?

We have the following situation. Our customer and we do not wont to route foreigner ip- address.

So we thought to make NAT in both ways on one router.

In that case we have to implement NAT on our and the Router at customer site.

Do you see any other possibility?


Re: NAT Source overlaod outside to inside?

Overload means that the inside users will use the same outside (source) address, while using the source ports to differentiate the different data streams. It is always the source address that is manipulated, and it is always from inside->outside (ie private to legal address).

For packets initiated in the other direction (legal to private), the source device will be sending a legal destination address and port, and there would be no way to differentiate the data streams based on this source port or address (since multiple legal devices could be using this same destination address and port). At the same time, there would be no way to differentiate the data streams based on the source information, since that is out of the control of the NAT receiver (it can't enforce the overload of the source info for an inbound packet).

I'm not sure that I explained this well, but hopefully it makes sense. I don't have any other suggestions for what you are trying to accomplish.

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