TP-Link TL-WR841N/ND: Installing OpenWrt as Wireless Repeater
WiFi repeater are used to extend the coverage area of your WiFi network. It receives your existing WiFi signal, amplifies it and then transmits the boosted signal. With a WiFi repeater you can effectively double the coverage area of your WiFi network.

WiFi is very convenient as it does not require a physical connection to your devices to receive internet but they can on occasion be unreliable if your existing WiFi signal is weak. At BehindTheSciences headquarters, some of our desktop PC are connected to the internet using USB WiFi dongle. Although they are good enough most of the time; they sometimes struggle to get a good strong WiFi signal from our main internet router.
We made an executive decision to upgrade our current network by either investing in a better main router or by using WiFi repeater. We happened to have a few of the TL-WR841ND kicking about from previous research activities and so we decided to convert them into repeaters. The TL-WR841ND cable routers are relatively cheap (Around £18/$26) and open source firmware can be loaded on them.
On this occasion, we decided to install OpenWrt on it as opposed to DD WRT or tomato.
Here is how we came about to configure them:
The very first thing that you need to do is: check the router version. The version of the router is displayed on the back of the router or can be obtained by logging into the router.
- Connect an ethernet cable between the router LAN port(not WAN) and your computer.
- In your favourite browser, enter http://192.168.1.1
You will be welcomed by a login screen; Enter admin for both the user and Password. Then browse to Systems Tools -> Firmware Upgrade.

Figure 1: TP-Link Firmware Upgrade Page
The Hardware version will be displayed as shown in Figure 1. In our case, we have a version 8.
The hardware version is also displayed on the back of the router.

Figure 2: TL-WR841N Router sticker
So head over to: https://wiki.openwrt.org/toh/tp-link/tl-wr841nd
Download OpenWrt for a version 8 model.

Figure 3: OpenWrt Page
Download the zip file and extract the contents. The firmware is a .bin format file. Rename the file to: “wr841nv9_wr841ndv9_en_3_16_9_up(150310)”
(The reason for renaming the file is because TP-Link software has a “safety” feature that prevents fake and open source firmware to be installed.)
Now you are ready to upgrade the router firmware to OpenWrt. Head back to the firmware upgrade page as in figure 1, choose the newly renamed file and click upgrade.
The upgrade process will start and the rooter will reboot to the new firmware. Do not disconnect the power during upgrade or you might brick the router.
Once the router reboots, you will be welcomed to the LuCI screen:

Figure 4: LuCI login screen
Log into the router with Username root and Password admin
- Now head over to Network->Interfaces->LAN
Configure a static IP:

Figure 5: LAN configuration
- Create a bridge in the Physical settings

Figure 6: Bridge settings
Join your existing main WiFi network
- Network-> Wifi-> Scan

Figure 7: WiFi settings
Finally create an AP and link it to the lan interface.
- Network-> Wifi-> Add

Figure 8: WiFi AP settings
That’s it! Happy streaming 🙂
We added some additional forwarding settings:
- Network-> Firewall

Figure 9: Forwarding settings
Feel free to comment. Any suggestion is most welcome.
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About The Author

behindthesciences
We are two engineers who work in the Electronic and Telecommunication industry. We regularly blog in our spare time.
11 Comments
You saved my day, man! Thank you.
You are most welcome 🙂
Hello when i perform figure 7 the router stop broadcast SSID even if i made the figure 8 still the same can you help please
Not sure why this would happen. This has worked for us and other people. Just to confirm, you used figure 7 to connect to your existing home/provider router?
I was looking everywhere for this…thank you very much!
Thanks man, after trying some very diferente configurations suggested by other pages, your’s worked first time, no problems.
Only one doubt:
The DHCP in LAN Interface shoudn’t be disabled?
Again, thank you very much!!!
We are glad that it helped. Yes, we believe that the DHCP should be enabled 🙂
hi there,
all works, thanks. but, this is creating a new SSID. Anyway to expand the existing SSID? Or that is a different function?
I think that you are talking about roaming functions. You could in principle name your new SSID as your main one and have the same password. However, handover might be a problem as your network tries to disconnect from one to the other.
Works perfectly! Thanks! I want to open some ports for game servers, and I want to know if you could help me with that, I have found some info of openning ports in openwrt in the internet but didn’t work.
I sat through about 14 hours before I hit this. Took just 10 minutes from there.