How NAT works

[cisconoval]

As of now I understood from CCNA book about how explicitly NAT is working. But here my query is, say

LAN : 192.168.1.x

WAN : 176.10.10.10

NAT IP : 193.100.10.10

how the router communicate with the entirely different susbnets without any routing. (i.e between WAN IP and NAT IP).

Is any MAC address is being used while routing?

Thanks in Advance

[network.king]

Hi,

In nat , the router is going to change the ip address of the source and going to replace with the Nat ip . Now nat ip becomes the source of the packet when it leaves the router .

There should be a default route in the router for the packet to go from your router to the SP and also a return routed in the SP network pointing to your wan of your router .

There is no mac address used .

Once the packet reaches your router , again the reverse happens .

Pls ref this link for good understanding

http://www.cisco.com/en/US/products/ps6640/products_white_paper09186a0080091cb9.shtml

regards

vanesh k