A network needs only one router to function. That said, when you replace your old Wi-Fi router with a better faster one, you can spend time trying to convince someone to take a five-year old router off your hands, or you can turn it into an external Access Point (AP). Placing this DYI AP at the far end of your home and connecting it to the new router (via a long network cable) is the best way to blanket your home with Wi-Fi. And this guide will show you exactly how to do it.
Your home Wi-Fi router has an embedded AP (or even two or three embedded APs in the case of a dual-band or tri-band router) in addition to its function as a basic router. APs broadcast Wi-Fi signals that wireless clients like smartphones, tablets, etc. can connect to.
For the purposes of this guide, let's refer to the new router that hosts your home network as Router A. The old and busted one you'll be converting into an AP is Router B. The objective here is to make Router B function as an external AP for Router A.
Note: Some Wi-Fi routers feature an Access Point mode (you'll see that in its features list if it does). If that's the case for your Router B, you can just turn this mode on and it will start working as an AP. This guide is only necessary for Wi-Fi routers that do not have this feature (or if you don't know how to turn the feature on) and is only appropriate for routers that have a web interface, which luckily is the case for most routers on the market.
General direction (for networking experts)
If you're comfortable with configuring routers and networking in general, what follows is the general direction you'll want to take. If you're new to networking, I'd recommend first reading this post about setting up a home router first. When you're done, follow the "Detailed steps" below.
1. Cover Router B's WAN (Internet) port with a piece of tape. You'll want to avoid using the port as doing so would prevent you from converting the router into an AP.
2. Find out what router A's range of IP addresses is. For example, if Router A's IP adress is 192.168.1.1 then we can safely assume its IP pool ranges from 192.168.1.2 to 192.168.1.254.
3. Manually set Router B's IP address to an unused IP within Router A's IP range. For example, you can make it 192.168.1.2. Just make sure you haven't and will not manually use this IP for any other device.
4. Turn off Router B's DHCP function.
And you're done. Now if you connect Router B (which is no longer a router) to Router A using a network cable (from LAN port to LAN port), it will function as an Access Point giving you better Wi-Fi range for your devices.
Detailed steps (for the beginners)
Step 1: Ignore Router B's WAN (Internet) port.
If your router doesn't feature a native AP mode, then you'll want to avoid using its WAN port at all. Using the WAN will make the router automatically function like a router because that's the intended role of the device: a router connects to the Internet and shares that connection with the rest of the network it hosts. That will no longer be the function of Router B in our project. Leave this port alone or cover it with a piece of tape to avoid using it by accident.
(Note that for routers that feature a native AP mode, you will actually make use of the WAN port. When in AP mode it will function as a LAN port, allowing you to -- and in this specific case only -- use port to add another wired device to the network).
Step 2: Find out what Router A's range of IP addresses is.
This is a two-part step. First you'll need to find out Router A's IP address. Connect a computer to Router A via Wi-Fi or with a network cable through one of its LAN ports.
If it's a Windows computer:
- Run the command prompt (you can search for cmd in the Start Menu, in Windows 10 or in Windows 8 just type cmd when you're at the Metro Start menu, then press Enter).
- At the Command Prompt window, type ipconfig then press Enter. You will see a lot of possibly confusing numbers and words, but the IP address located to the right of "Default Gateway:" is the address of the router. That's the number you want.
Or on a Mac:
Head to System Preferences > Network > select the current connected connection (you should see a green dot signifying the connection is working)> click on Advanced > on the TCP/IP tab, look for "Router:". The router's IP address will be shown next to it.
Once you have the router's IP address (which always consists of four groups of numbers separated by a dot in between each group) use it to determine its IP range. The range of numbers you'll be able to select from will use the same numbers for the first three groups with the last group ranging from 1 to 254. The router's current IP address will not be available to use.
For example, if the router IP address is 192.168.1.1 then the IP pool of addresses will range from 192.168.1.2 to 192.168.1.254. If the router's IP is 192.168.1.254 then the IP range will be 192.168.1.1 to 192.168.1.253. When a device is connected to Router A and has an IP address within its IP range, it will be accepted as part of the network. It would take a whole separate video and an entire other article to explain why it works this way, but just trust that it does.
For this guide, we'll assume 192.168.1.1 is Router A's IP. This will also likely be your case because many home routers (from Netgear, Asus, D-Link etc.) tend to use this IP address by default.
Step 3: Set router B's IP address as an unused IP within the IP range of router A (don't worry, we'll explain below what that means).
Connect a computer to Router B via Wi-Fi or with a network cable through one of its LAN ports to find out what the router's current IP is (repeat the first part of step 2 above to do this).
Log into the router's web interface by pointing a browser to its IP address. Within the interface, navigate to the section where you can change its default IP address. Depending on the router, this section tends to be called Network, LAN or Setup. Change this IP address to one of those in the IP pool determined in the second part of step 2 above. For example, if Router A's IP is 192.168.1.1, you can make the IP of Router B 192.168.1.2 (make sure that you haven't manually assigned this IP to any other device, and if you have, choose a different IP address instead) then save the changes. Router B will now likely restart to apply the changes, which will take a minute or two to complete.
Step 4: Turn off Router B's DHCP Server function.
Log into Router B's interface again by pointing a browser to its new IP address you manually set in step 3 (in our case, it was 192.168.1.2) then again navigate to its LAN or Network setup section. Here, disable its DHCP server function. This is one of a main functions of a router that leases out IP addresses and right now you don't want it to do that, so make certain it's off. Save the changes and you're done.
(Depending on the interface, some routers allow you to do step 3 and 4 as one step without restarting).
Now Router B, when connected to Router A using a network cable, will work as a both a switch (allowing you to use its LAN port to add wired devices to the network) and an access point. You can always login to either router's interface using their IP address -- 192.168.1.1 (Router A) or 192.168.1.2 (Router B) in this guide's case -- to change their settings or customize their Wi-Fi networks.
If you don't change any settings, Router B (now working as an AP) will still be named whatever you called it when you were using it as a router. You can change its name to be the same as that of Router A's if you want devices to connect to either one automatically, or keep the names separate if you want to be certain if you're connected to Router A or Router B. Either way, all devices connected to either router will be part of the same network.
As I said before, this is a great way to make use of an old router and to blanket your home with a Wi-Fi signal. Good luck and have fun!