When a room in your home or office is desperately short of wired ports and the wireless signal barely penetrates the walls, many users buy new equipment. However, it often ends up collecting dust on a shelf. old router, which is quite capable of solving both problems simultaneously. Converting a router into a switch with access point functionality is a cost-effective and efficient way to expand your network.
The method involves using the device solely for data transmission at the physical layer, removing its routing functions, such as IP address assignment and NAT. This results in additional LAN ports and a powerful Wi-Fi antenna operating on the same network as the main router. This allows devices to "see" each other, which is critical for local file shares and printers.
The repurposing process doesn't require in-depth knowledge of network protocols, but it does require careful input of parameters. An error in addressing configuration can lead to a complete loss of connection on the local network. Below, we'll walk you through a step-by-step procedure that will work for most popular models from TP-Link, Asus And Keenetic.
Equipment preparation and compatibility testing
Before you begin, you need to make sure that your secondary device supports bridge mode or has the ability to manually shut down the server. DHCPAlmost all modern models have this functionality, but the interface may have different names. You'll need a computer with a network card and two patch cords.
It's important to understand that we'll be using only LAN ports. The WAN port (often blue or yellow, separate from the others) is typically not used in this setup, unless the firmware has a special "Access Point" mode that automatically switches the port operation logic. Without such a mode, the WAN port will remain "dead."
β οΈ Note: If your old router is a very old model (more than 10 years old), it may not support disabling the DHCP server. In this case, using it as a switch will not work, as it will cause constant IP address conflicts.
First, connect the computer and the secondary router with a network cable. Do not connect this device to the main ISP network or the main router yet. Configuration should be performed in isolation to avoid address conflicts if they accidentally overlap.
Changing the IP address of the secondary router
The first step is to log into the secondary device's web interface. By default, most routers have an address 192.168.0.1 or 192.168.1.1If your primary router is already using the same range, a conflict will occur. You need to change the secondary device's IP address so that it's in the same subnet but doesn't overlap with the primary one.
For example, if the main router distributes addresses starting with 192.168.1.1, then the second device should be assigned a static address 192.168.1.2 or 192.168.1.250This will allow you to access its settings in the future by simply entering this address in your browser. The changes will only take effect after you restart your device.
What to do if the main router address is unknown?
On a computer connected to the main network, open a command prompt (cmd) and enter the command ipconfigFind the "Default Gateway" lineβthis is the IP address of your main router. Use it as the basis for addressing the second device.
After changing the IP address, your computer will lose connection to the router because it will be on a different subnet. You will need to reconfigure your PC's network adapter to obtain an IP automatically or manually assign a static address to continue setup.
Disabling the DHCP server
The key point of this entire guide is disabling the dynamic address assignment service. Only one active DHCP server can be running on a network (usually the main router). If you leave this feature enabled on the second device, your devices will start receiving incorrect gateway and DNS settings, resulting in no internet connection.
Find the section in the menu that is usually called LAN, Network or Local NetworkThere should be a tab inside. DHCP Server. Switch the slider to the position Disable or uncheck the box EnableSave the settings with the button Save or Apply.
Your device is now no longer a full-fledged router but a managed switch. It will transparently forward IP address requests to the main device on the network. All clients connected to it will receive addresses from the main router's pool.
Setting up a wireless Wi-Fi network
To enable Wi-Fi sharing, you need to configure the wireless module correctly. Go to the section Wireless or Wi-FiHere, it's important to set the network name (SSID) and password. You can create a copy of the main network for seamless roaming or create a separate network with the "_Ext" prefix.
If you want devices to switch between routers automatically, the network name (SSID), encryption type (usually WPA2-PSK), and password must exactly match the main router's settings. However, the broadcast channels must be different to avoid interference.
It is recommended to manually select channels to ensure they do not overlap. For the 2.4 GHz band, channels 1, 6, and 11 are optimal. If the main router broadcasts on channel 1, set the second device to channel 6 or 11. This will ensure maximum speed and connection stability.
Physical connection and wiring diagram
After completing the software setup, the physical connection stage begins. Take a network cable and connect any LAN port on the primary router to any LAN port on the secondary device (which we configured as a switch). As mentioned earlier, the WAN port on the secondary device remains free unless special bridge mode is enabled in the firmware.
The connection diagram looks like this: The internet cable from the provider enters the WAN port of the main router. From the main router's LAN port, the cable goes to the LAN port of the secondary device. Computers, TVs, or game consoles can be connected to the secondary device's other LAN ports.
The table below shows the main differences in port connections depending on the operating mode:
| Opening hours | Connecting the cable from the main router | Ports used | WAN function |
|---|---|---|---|
| Router mode | To the WAN port | WAN + LAN | Active (receives IP) |
| Switch mode (our case) | To the LAN port | LAN only | Not used |
| Access Point (AP) mode | To WAN or LAN port* | Depends on the model | Frequently reprogrammed |
β οΈ Note: On some modern models (for example, Keenetic or Asus with Merlin firmware), when switching to "Access Point" mode, the system automatically reassigns the WAN port to the LAN port. In this case, the cable can be plugged into any port, but in the classic "switch" configuration, we only use the LAN port.
Network operation check and diagnostics
Once the cables are connected, the indicators on both devices should light up in the appropriate color. Typically, a blinking LAN indicator indicates data transfer. Check the connection on the client device: connect the laptop to the new switch via cable or Wi-Fi.
Open command prompt and type ipconfig (for Windows) or ifconfig (for Linux/Mac). Make sure the IP address, gateway, and DNS server are assigned by the primary router, not the secondary one. The default gateway should point to the primary device's address.
βοΈ Checking successful setup
It's also worth checking your data transfer speed. Run a speed test or try transferring a large file over your local network. If the speed is significantly lower than expected, check the cable quality (it should be 8-wire) and ensure there's no significant interference.
Typical problems and solutions
During setup, users often encounter the inability to access the secondary router's web interface after changing its IP address. This can be resolved by assigning a static IP address to the computer's network card in the same subnet. Another common problem is a network loop, which occurs when connecting two routers with two cables simultaneously.
If Wi-Fi works but there's no internet connection, check your DNS settings. Sometimes providers block connections if they detect multiple devices with the same MAC address (cloning), although this is rare in a switch setup. Make sure PPPoE or L2TP mode isn't enabled on the secondary device, if it's left over from a previous use.
The secret to stable operation
For maximum stability, update the secondary router's firmware to the latest version before beginning setup. This will fix known security issues and improve wireless performance.
If your connection is constantly dropping, try reducing the transmitter power on the secondary router if it's too close to the primary one. Signal overlap can destabilize client devices, causing them to bounce back and forth between the two signal sources.
The benefits of this configuration for the home
Using an old router as a switch not only saves money but also reduces power consumption compared to purchasing new active network equipment. You get a full-fledged wired infrastructure in a remote room without running new lines to the main router.
In addition, this scheme is ideal for organizing guest network or smart home segmentation. You can assign a separate SSID to IoT devices, restricting their access to the main computers simply by setting up rules on the main router, as all devices are now in the same logical space.
In conclusion, it's worth noting that this configuration is standard practice in small office network administration. It provides flexibility and scalability: you can revert the settings at any time and use the device as a full-fledged router for a different provider or application.
Is it possible to connect two routers via Wi-Fi instead of a cable?
Yes, this is called WDS or repeater mode. However, the speed will drop by at least half in this case, since the channel is used for both receiving and transmitting data. A cable connection (switch) is always preferable for stationary devices.
Do I need to set the same passwords on both routers' Wi-Fi?
For ease of use, yes. But seamless roaming (when the phone doesn't lose signal when moving from room to room) requires more complex settings (802.11r/k/v), which not all older routers support. A simple password match will ensure automatic reconnection, but with a slight delay.
Will this instruction work for routers from different manufacturers?
Absolutely yes. The TCP/IP protocols operate on the same principles for all devices. The key is that both devices support standard network protocols, which is true for 99% of equipment manufactured after 2010.