I have a home network that has an ActionTec Router/DSL Modem plugged into the phone line, with my desktop computer plugged into it.
I also have a LinkSys WRT54G2 Wireless-G Broadband Router plugged into it, to which I connect laptops, Ebook readers, etc.
The WRT54G2 is configured to run as a DHCP server. The ActionTec is serving addresses in 192.168.0., the LinkSys is sering addresses in 192.168.1..
Things work fine, for a while. Laptops can connect to the internet, without a problem. For a while.
After what can be a few weeks or a few hours, laptops fail to connect. Or rather, they seem to connect to the LinkSys, pass authentication, and then fail to obtain an IP address. It looks like the LinkSys' DHCP server is failing to issue new addresses.
A power cycle of the LinkSys fixes everything, for a while. But a few days later, and the problem will be back.