Be careful and avoid using an address that is within the DHCP range allocated to the Zyxel. Since the Zyxel's IP address is 192.168.1.1, you must assign an address like 192.168.1.x to the Belkin. They also mention that the secondary router (your Belkin) must be assigned a static IP address that’s within the subnet of the Zyxel. I assume that the uplink port you said you've used is the WAN port. Since you have set up your Belkin as your secondary access point and the Zyxel as your main router, D-Link's advise is that you do not use the WAN port on the Belkin. However, they go on to describe how it can be done.

The first recommendation from D-Link was not to use two routers. I suggest you re-read this since it seems to address your problem. In the previous input I made to this thread I quoted some advise which I pulled from the D-Link web site. Wow, a response to a 2 1/2 year old thread. Click Disable and then click apply.' ***End of D-Link advice To disable DHCP, go into the routers configuration > Home > DHCP. If you are using another router, DHCP server, or Internet connection sharing software, change the LAN IP address of the router to an IP in your subnet (192.168.0.2). Step 2 Depending on your network setup, you may need to change the LAN IP address of router B. Step 1 Do not use the WAN port on router B. Router B is the router you want to use an access point or switch. Router A is the router you want to use as the router - connected to the modem. To use your router as an access point only, please follow the steps below: You may want to return it and purchase an access point (wireless) or a hub/switch.

It is STRONGLY recommended that you do not use 2 routers. There may also be issues with connecting unlike router brands. Their first recommendation is 'don't do it'. The was under their notes for a DI-624 wireless G router. With regard to connecting your two routers properly, the D-Link Knowledge Base has a procedure to accomplish this. You must (1) make sure you have a unique SSID, (2) activate WEP security, (3) use MAC filters to restrict access to designated MAC addresses, and (3) do not broadcast your SSID. The only way to make sure unauthorized users cannot use your wireless router is to secure it. If you have a security issue a 2nd router is not your best solution.

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