If you have a spare Wi-Fi router to the main one, you can link both together to access the internet. Some use cases:

• Extend the Wi-Fi range to cover areas that were not covered by the main router. This is often the case when you got a free router from the internet provider.
• Turn the secondary router into the guest router, not all routers have the guest built-in feature. So, you can share your Wi-Fi password without fear of exposing your password for the main router.

Connection setup

Linking one router to another is pretty straightforward, here are the steps with an explanation of how and why to do this:

• In the main router - adjust the DHCP address pool start IP to make a room for the secondary router IP address, ex. 192.168.0.10 - 192.168.0.254. That’s needed because the secondary router’s IP address must be fixed and not dynamically allocated.
• In the secondary router - disable DHCP, that’s needed to prevent the conflict when both routers start allocating an IP address for the new device.
• In the secondary router - set the Gateway IP address that is not in a range of DHCP start/end pool allocation addresses.
• In both routers select different channels to prevent interfering with each other.
• Connect both routers using a network cable, use LAN ports, not WAN ports.

Now, you can connect to the Wi-Fi using a secondary router and check in the router admin interface - traffic that is going through (number of packets, bandwidth, etc).