Dynamic NAT configuation

[Steve]

Hello guys,
I have a question regarding the configuration of dynamic NAT.
As a first step to configure the dynamic NAT we should define a pool of addresses to be allocated as needed. Let's assume i choose as mentioned in Mr Todd's book the addresses btw 170.168.2.2 and 170.168.2.254 so the config would be:

Router(config)#ip nat pool POOL1 170.168.2.2 170.168.2.254 netmask 255.255.255.0

What does the netmask mean? and is it a must to put it in the configuration?
If it is working same as subnetmask why it's called netmask then.

Thank you

[Fuzz]

The terms netmask and subnet mask are interchangeable. Consider a class C subnet mask of 255.255.255.0. There are no subnets here, so netmask is more appropriate, but either term is acceptable. Sometimes it's even referred to as simply 'mask'. All 3 terms mean the same thing.