I have a similar Belkin wireless router, and I'm pretty sure it will will let you solve the problem easily. Use a web browser to log in to the router and go to the LAN settings page. Find the option called "Lease Time" and change it to Forever, or a week. That will reserve a specific IP address for your N800 (and any other computer that checks in to your network) forever, or whatever time period you set. You N800 will get the same IP address every time.