NAT ROUTER

[mmtantawi]

Dear All,

I HAVE cisco 1841.

it has 2 interfaces.

the first one which is f 0/0 is have public ip from my ISP.

the other one is normal, and i am going to give it 192.168.1.100 / 24.

now i have 3 subnets totally diffrent .

i want to create 3 subinterfaces from f0/1.

my question is , how many subinterfaces can i add under the f 0/1 ?

and can i make this Router work as NAT ( overloading ) but all the 4 subnet will use the same public IP Address ?

can it be done as per this diagram ?

please update me.

[Edison Ortiz]

Mohammed,

From your diagram, it looks like you have a 3COM switch between the 1841 and the 172.16.0.6 device (Cisco Switch ?).

Any reasons you aren't connecting the 1841 directly to this device avoiding the extra hop on the 3COM switch ?

You can create the subinterfaces in the 1841 as you stated but keep in mind you need to trunk the link at the other end (3COM switch) so it can tag each VLAN you've created.

Based on your diagram, I recommend performing the interVLAN routing at the Core (4507 switch), send the default route over to the 1841 running as single interface -let's say 192.168.1.100/24- and do the NAT there.

Much simpler configuration.