QUOTE(btech @ Nov 11 2004, 03:02 PM)
Maybe that's why. I leave my cable modem on all the time, even when my computer is off (because it's on the other side of my apartment). The only time I've ever turned off the modem is when I needed to power cycle it.
It will not make a difference if you turn it off or not if your ISP decides to change it.
The DHCP assignment is a lease that contains an expiration time. As the lease gets close to the expiration time, the leasee can request renewal. The renewal request will first go to the DHCP server that the lease was obtained from. If it is not able to get a renewal, it will broadcast for any DHCP server to give it an address.
You have to leave your equipment off for longer than the lease period for it to affect your assignment. Some ISPs have very short lease periods though.
Your address jump probably means that your ISP is reorganizing it's address pools for various reasons.
In addition to getting an I.P. address, the DHCP assignment process delivers other information to the computer, including the subnet name, DNS servers, and routing information. In some cases the subnet name is required to make sure that you reach the preferred (or only working) mail, news, and other local servers for your ISP.
Personal Opinion Only