I am getting Adelphia Powerlink (a local cable internet provider in my area) this weekend and I will be connecting it to a Red Hat 6.2 computer that will serve as the Internet gateway for my network via IPMasq'ing. I know Adelphia refreshes their IP every few minutes, day, months or whatever.

Does anyone know if Linux automatically handles these refreshes or do I have to manually restart the network card that the modem is connected to in order to handle the new IP?

Thanks in advance for your help!
Andy