Question : How do i config using the ios,a cisco router NAT when my isp uses dhcp.?
i dont have a static ip but instead my isp uses dhcp. so how do i configure nat on cisco routers using the ios cli.
cisco router

Best answer:

Answer by Lanwanprofessional.com
Hello,

This is no problem at all for cisco. You can instead of specifiyng IP, specify the interface name (or subinterface).

We have recently posted about it. Please check this post:

http://cs-ms.blogspot.com/2009/06/configuring-nat-dynamic-translation.html

The only thing you need to change is this line:

GatewayRouter(config)#ip nat inside source list 1 pool OUTSIDE

to

GatewayRouter(config)#ip nat inside source list 1 interface fastEthernet 0/0

This is assuming that your public IP is assigned to F0/0 (via DHCP).

In the furute you may find usefull also services like no-ip.com, dyndns.com, dnsalias.net in order to have dns hostname assigned. So you will have a chance to connect for example from work/school to your router using for example: youhome.dyndns.com