Most people have probably faced the problem of not being able to provide good Wi-Fi coverage for every room at home, and this problem is particularly severe in Hong Kong due to the use of concrete walls. In the past one would consider wiring the rooms with Ethernet cables or installing Wi-Fi extenders.  Today I am going to review a third option: powerline network adapters. They work by sending signal through electricity wirings, and units plugged into sockets under the same meter and will automatically form a network. To get internet access, simply connect one of the adapters to your broadband router with an Ethernet cable. Furthermore, there are Wi-Fi-broadcasting models that allow you to extend Wi-Fi coverage.

This hands-on features kits from two Chinese brands: a budget model from Tenda and a mid-range model from TP-Link. Budget models differ from higher-end ones in two major ways: First, budget models usually have maximum theoretically speed of 200Mbps, whereas higher-end ones have speeds up to 600Mbps. Since these numbers are theoretically limits, practical speed will only be a fraction of that, as my test results will show below. Second, high-end models sometimes have a pass-through socket that could be a life-saver if your room is in short of wall sockets.

Test models: Tenda P200/P201 kit (~HK$460) and TP-Link TL-WPA4230P Kit (~HK$650). Each kit comes with one cable-only unit and one Wi-Fi-broadcasting unit.

Test environment: Hong Kong Broadband 100M connection. Test conducted with speedtest.net with a Fujitsu Q584 tablet.

Basic installation: Easy. Both kits work immediately once I plug the included units into wall sockets.

Advanced Installation: you can build a network where devices roam between different Wi-Fi sources depending on their strength by setting the same SSID, encryption mode and password for all Wi-Fi access points on the network. The TP-Link unit has a button for automatically cloning my original Wi-Fi router’s settings via WPS, whereas for the Tenda unit I need to manually change settings via a browser. In practice I have never found WPS particularly easy to use, and it took several tries before the TP-Link unit was able to clone settings successfully. Furthermore, for unknown reasons I could not access the TP-Link’s settings panel the way the manual describe.

Speed: My HKBN connection has an average speed of around 60Mbps. Plugging the powerline units directly into wall sockets, I got the same speed with the TP-Link unit, whereas for the Tenda unit I only got 30Mbps at best. The results were the same regardless of whether I use an Ethernet cable or Wi-Fi, so the bottleneck is the Tenda unit itself. Speed drops dramatically if you plug the units into an extension cord—the average speed was only 3Mbps in my test.

Conclusion: Powerline network adapters present a very convenient way to extend your home network. Base on my test results, I would recommend spending the extra money to get the higher-end models due to the large speed difference.

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