forcing new dynamic ip address

[Ernie Luzar]

Hello List;

I have a "home service" account from my ISP. The ISP issues an dynamic 
ip address which has not changed in 12 years.

My host has 2 NICs, one which is not used. I know if I plug the internet 
cable into the un-used NIC and make the appropriate config changes and 
reboot I will get a different dynamic ip address.

Is there a simpler way to expire the lease to force the ISP dhcp to 
refresh with a different dynamic ip address?

The goal is to have a cron job that gets a different dynamic ip address 
assigned to my host's front door every a week.

Just another level of security to make it very hard for the script 
kiddies from finding any open ports I may have.

Thanks for the help.