WAN or LAN port - what's the difference?

[gihe]

I have an old Belkin ADSL wireless router which doesn't support newer devices very well (e.g. iPad) so I've turned off the wireless and replaced that functionality with an Airstation WHR-G300NV2.

The AirStation is connected via a LAN port to a LAN port on the Belkin and it's configured itself as an AP (switch is set to Auto).

 

The AirStation gets its IP address from the Belkin via DHCP and shows up as a DHCP client on the Belkin admin page.

 

The thing I don't get is that, in this configuration, I cannot access the AirStation admin page. It times out. I can't even ping its IP address. The only way I can get to the admin page is by connecting the AirStation from its WAN port.

 

Why would that be? What's going on here?

[Artjohn]

Disconnect the Buffalo, connect directly to a lan port on it, and Set the Buffalo to a static IP address outside the range of the Belkin.

 

See FAQ 4 above and 

 

http://www.smallnetbuilder.com/wireless/wireless-basics/30355-how-to-add-an-access-point-to-a-wireless-router