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ZyXel PLA4231 500 Mbps Powerline Wireless N Extender review: Good, but not quite good enough

Already have power-line Internet at home and now want to extend the reach of your Wi-Fi farther? The ZyXel PLA4231 500 Mbps Powerline Wireless N Extender is the answer.

Dong Ngo SF Labs Manager, Editor / Reviews
CNET editor Dong Ngo has been involved with technology since 2000, starting with testing gadgets and writing code for CNET Labs' benchmarks. He now manages CNET San Francisco Labs, reviews 3D printers, networking/storage devices, and also writes about other topics from online security to new gadgets and how technology impacts the life of people around the world.
Dong Ngo
6 min read

If you want to extend your Wi-Fi network to the far end of a large home, the best way is to run a network cable there and connect it to another access point (or Wi-Fi router). But running network cables in an aesthetically pleasing way is a challenge, so the second-best way is to get a pair of power-line adapters, such as the recently reviewed Actiontec PWR511K01, and another access point. Or you can get the ZyXel PLA4231 500 Mbps Powerline Wireless N Extender.


ZyXel PLA4231 500 Mbps Powerline Wireless N Extender

The Good

The <b>ZyXel PLA4231 500 Mbps Powerline Wireless N Extender</b> is a two-port power-line adapter with built-in Wi-Fi and hence extends a home network for both wired and wireless clients.

The Bad

The ZyXel PLA4231 doesn't support Gigabit Ethernet or dual-band Wi-Fi, and, without a required second power-line adapter, it's rather expensive.

The Bottom Line

Current power-line users with large homes will benefit from the ZyXel PLA4231's network extension capabilities; however, there are alternatives that offer similar benefits for less.

The ZyXel PLA4231 is basically a two-port power-line adapter that comes with a built-in Wi-Fi access point. This means apart from being able to host two other wired network devices in some remote part of your house, it can also create a new Wi-Fi network there for wireless clients. Per the HomePlug AV IEEE 1901 standard, the ZyXel PLA4231 should provide data speeds of up to 500Mbps. In reality its speed is, unfortunately, much lower than that, both for wired and wireless clients, due to the lack of Gigabit Ethernet and dual-band Wi-Fi support.

To add injury to the insult, at a street price of around $120, without a second power-line adapter included, the ZyXel PLA4231 is not cheap.

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If your home network is already power line-ready, the ZyXel PLA4231 is a decent addition thanks to its two network ports and built-in Wi-Fi. First-time power-line buyers, however, will find it a better deal to get an Actiontec PWR511K01 kit, which costs just $50, and a separate budget Wi-Fi router or an access point.

Design and features
The ZyXel PLA4231 is not the first power-line Wi-Fi extender kit I've seen. A couple of years ago I reviewed the Netgear XAVNB2001, which offered a similar feature. The Netgear, however, supported only the HomePlug AV Powerline standard, which caps at just 200Mbps, while the ZyXel PLA4231 supports the HomePlug AV IEEE 1901 standard (also known as Powerline AV 500), which offers up to 500Mbps.

The ZyXel PLA4231 has two network ports to host two wired devices at the far end of a power-line connection.
The ZyXel PLA4231 has two network ports to host two wired devices at the far end of a power-line connection. Dong Ngo/CNET

In reality, however, the ZyXel PLA4231 is not much faster than the older Netgear XAVNB2001 because its network ports are regular Ethernet, which is capped at 100Mbps. This means that at most a wired connection using it will have a speed of 100Mbps, not 500Mbps. The situation would improve a great deal if the PLA4231 supported Gigabit Ethernet, instead. In its defense, the Actiontec PWR511K01 doesn't support Gigabit Ethernet either.

The ZyXel PLA4231's built-in Wi-Fi supports the 300Mbps dual-stream single-band 802.11n standard and works only in the 2.4GHz frequency. For this reason, the real-world output speed is also much lower than 300Mbps. I wish it supported dual-band to also offer a Wi-Fi signal on the faster 5GHz band.

Unlike the Netgear XAVNB2001, which comes in a kit that includes a second power-line adapter, the ZyXEL is a single unit. This means it's useless just by itself, as you need at least two adapters to create the first power-line connection. For this reason, first-time power-line users need to purchase another power-line adapter with the ZyXel PLA4231. You can get basically any power-line adapter on the market but it's better if you get that supports the same standard, such as one on this list. I tried the new ZyXel with a few power-line adapters from different vendors, including the Actiontec PWR511K01, and it worked with all of them. Most existing power-line adapters come in a kit of two, however. ZyXel also has a Powerline AV 500+ adapter of its own, the PLA4205, that will be reviewed later.

The PLA4231 has a snap-on design and is relatively compact but not compact enough to keep the power socket area clear, so it might obstruct access to adjacent receptacles. On top is an array of small LED lights that show the statuses of power, Wi-Fi, power-line connectivity, and the two Ethernet ports. The two network ports are located on one side of the device. As mentioned above, they don't support Gigabit Ethernet (1000Mbps), just regular Ethernet (100Mps), so it can't take full advantage of the 500Mbps Powerline AV 500+ standard it supports.

On other side of the PLA4231 are a power on/off button and two smaller buttons. One of them is to reset or change the device's encryption, and the other is for the Wi-Fi Protected Setup (WPS) feature that helps with the setup process.

Setting up the ZyXel PLA4231 is either very easy or a challenge, depending on your situation.

In terms of hardware, it's easy; you just have to make sure there's another power-line adapter at the router's side, then plug the PLA4231 into another power socket of the house and there should be a power-line connection between the two. Now you're done, though if you like you can connect up to two other wired devices to the PLA4231.

The ZyXEL PLA4231 need another power-line adapter to work. It's here working with one from Actiontec.
The ZyXEL PLA4231 need another power-line adapter to work. Here it's working with an adapter from Actiontec. Dong Ngo/CNET

It gets harder if you want to use the device's built-in Wi-Fi network. Now there are two scenarios. In the first, if your existing network is already Wi-Fi-enabled (most networks are if run on a Wi-Fi router) and the router supports WPS, then things are easy. You just need to first connect the ZyXel PLA4231 to a power socket within the range of the existing Wi-Fi network. Then press the WPS button of the router, then do the same on the PLA4231 within two minutes. This will copy the existing Wi-FI network's setting to the PLA4231. Now move the PLA4231 to a power socket in the area you want to extend connectivity to, and you're done.

However, if the existing router doesn't support WPS, or is not a Wi-Fi router, things will be a bit harder. This is because the ZyXel PLA4231 comes with a default IP address of and you can get to its Web interface by pointing a Web browser from a connected computer to this IP address. But this only works if your existing router also belongs to the same subnet, meaning if it has an IP address in the 192.168.1.x format. If no,t you might need to temporarily change the router's IP afdress to before you can set up the ZyXel PLA4231. The good news is that many existing routers' default address is, so you might not run into any problem at all. For more on Web interfaces and default IP addresses, check out this post on how to set up a home router.

Once you've gotten to the Web interface, the rest is rather self-explanatory. You can set up the Wi-Fi network to your liking and change other settings of the device.

I tested the ZyXel PLA4231 both as a power-line adapter and a Wi-Fi access point, and it generally performed well.

As mentioned above, the device's wired speed is limited by that of the Ethernet standard, which caps at 100Mbps, and in my testing it offered 90Mbps. This is about as fast as Ethernet can be after overheads. Compared with other Powerline AV 500+ adapters that support Gigabit Ethernet, of course, this was much slower.

In Wi-Fi tests, the ZyXel PLA4231 also offered the expected speed of a regular single-band 802.11n device. In a close-range test with clients placed about 15 feet away, the PLA4231 averaged 65Mbps. When I increased the distance to about 100 feet, the speed was reduced to 24Mbps. And 100 feet or shorter is about the best range you can expect from the PLA4231. It can offer longer range, up to about 200 feet, but farther out the connection gets very slow. This is rather typical performance for a single-band 802.11n access point.

The ZyXel PLA4231 easily passed our 48-hour Wi-Fi stress test, during which it didn't disconnect once. The device gets a little warm while operating but not warm enough to cause concern.

Power-line adapter performance (in Mbps)
(Longer bars indicate better performance)
ZyXel PLA4231
Reference 802.11N 2.4GHz Wi-Fi

CNET Labs 2.4GHz Wireless-N performance score (in Mbps)
(Longer bars indicate better performance)
Cisco Linksys E4200v2
Trendnet TEW-692GR
Netgear WNDR4000
ZyXeL PLA4231
WD My Net N900 HD
Asus RT-N66U
Netgear R6300
Belkin N750 DB
D-Link DIR-857
Netgear WNDR4500
Synology DS213Air
Asus RT-AC66U
D-Link DIR-865L
Belkin AC 1200 DB

The ZyXel PLA4231 500 Mbps Powerline Wireless N Extender is a missed opportunity due to the lack of support for Gigabit Ethernet and dual-band Wi-Fi, which would greatly increase its value and performance. Given what it does and how much it costs right now, it would still be a good addition to a home network that's already power-line-ready.


ZyXel PLA4231 500 Mbps Powerline Wireless N Extender

Score Breakdown

Setup 7Features 7Performance 6Support 8