This article explains the steps to follow to make your old router as an access point. A home network was upgraded with a fiber connection, for which a new router supporting fiber port was required. The old router is then made as a an access point which connects to the router. The following are the steps used for the setup.
Connect the fiber cable (thin yellow cable) from the ISP to the appropriate port on the new router (white).The port is underneath the router due to which it is not visible in the screenshot. Connect the LAN port on the new router to the WAN port on the old router (black) using a network cable (Thick yellow cable). This is as shown in the below screenshot.
Setup the IP address for the WAN port on the old router. There are two options here. The WAN port can be configured as a DHCP client , if the new router is configured as a DHCP server. If the DHCP server is not used, IP addresses should be configured manually. As an example, the LAN interface of the new router is configured as 192.168.1.2 and the old router is 192.168.1.3. Ensure that both belong to the same network address.
Setup the DHCP Server on the old router. The network address range should be different from the above range which is 192.168.1.0/24. The DHCP server on the old router is configured from 192.168.2.2-192.168.2.50, assuming that number of users connecting to it would be maximum 50. The LAN IP address of the old router is configured as 192.168.2.1.
Configure the wireless network with name (SSID) and security parameters like WPA. Setup the clients or devices on the network with appropriate security wifi and security parameters. Connect the clients to the wifi network on the old router, which would then behave as an access point.
By following the above steps, the users on the network can connect to the old router, which would then forward all packets to the new router for internet access.
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