Review: ZyXEL PLA400 and PLA401 HomePlug Networking Adapters

Don Bradbury brings the Internet a little nearer with these easy to use plug-ins

Product	PLA400 and PLA401 HomePlug Networking Adapters
Company	ZyXEL
Web	www.zyxel.co.uk
Price	PLA401 £110.74 inclusive, from www.digitalkind.co.uk
We like	Fast, stable, local and Internet connectivity; excellent range
We don't like	Unavoidable cabling
Rating	9/10
Requirements

While, these days, WiFi is all the rage for connecting to the Internet with your home computers, we should not forget that there are alternative ways of doing the job. Using the network of wires that’s already built into your home or office, in the form of the ring main carrying the electricity, would appear to be a sensible thing to do.

The ring main can already be used for adding telephone extensions, indeed such technology was in service during these trials. So to keep the mains voltage at bay, and to suppress the spikes and other nasties which are associated with mains electricity was a technology that had been fundamentally conquered long ago. The remaining technological advance was to permit higher connection speeds. So now, with these units, we see up to 200Mbps capability, and that can more than compete with your typical wireless connection.

Sundry companies have produced such an adapter, among them ZyXEL. Their PowerLine HomePlug adapters simply plug into a mains socket and, via a provided Ethernet cable, connect to your computer, taking the signal from your existing router, previously set up with it’s particular configuration.

Other services may be suitable for connection, among them a NAS device (Network Attached Storage), digital media streamer, VoIP phone, webcam, network print server, gaming console, or a printer as easily as your desktop or laptop PC, provided they are suitably equipped.

Connecting

Starter packs of these devices bring the bare minimum of two units, though you can then add further single units, and connection to a computer simply involves attaching the provided Ethernet cables to each unit, plugging the first into your existing router and the second into a remote mains outlet, and then it's cable into your chosen device.

When this was complete, an Internet connection was established for us in a trice, even quicker than a WiFi connection would typically search around for. Using these, there was no more running out of wireless range, and no more concerning ourselves over drop-outs in signal strength due to walls, steel in the building structure, or other obstructions that can easily drop a WiFi connection to a snail's pace.

We were pleasantly surprised to find that, although the instructions stipulate the mains sockets you use should be primary, that is, not on the end of an extension cable, we were able to string together all the extension leads we could lay our hands on without any perceptible drop in connection speed or quality of reception. That, however, may depend on how clean your electricity supply is on the ring main.

We used the SpeedTest web site to check this, and whether our connection was as direct as we could make it, though nevertheless at the extreme end of the ring main, we still recorded figures of 3.5Mbps download and 370Kbps upload. This was as fast as our Internet service provider ever gives, and it was maintained when we extended this to 19 metres via mains extension cables, which included no less than three plug-and-socket connections. Further, we had the router end plugged into a surge suppressor which, in turn, also ran off the end of an extension cable. Not ideal, you might think, but it worked nicely in our case.

The Internet connection

A very fast Internet service resulted, and there was not the slightest sign of drop-outs or interruption in the connection. Very impressive!

On the downside, the Ethernet cables provided for the PLA401 units were only one meter long, which meant we were obliged to have the computer in close proximity to the PowerLine unit. Still, we found even that preferable to finding ourselves out of range of our usual WiFi connection in particular locations behind multiple walls. We must remember that with WiFi it’s not just the masonary thickness of wall that’s obstructive; many times the WiFi radio signal will have to pass through walls at a shallow angle, thus making them effectively several times their nominal thickness. All of this attenuates the signal strength of a WiFi connection. PowerLine connections, on the other hand, are not susceptible to this type of interference.

Blue LEDs on each unit display power and the connection status, and that’s about it. Security of the connection was ensured automatically via the PowerLine units themselves (regardless of what you have set on the router), and unless you need access to further tweaks, beginners don’t even have to resort to the CD which contains details of other adjustments you can make if you feel the need. The entire assembly really was plug-and-play.

The PLA-400 units, which we also looked at, had a mains supply cable in and the Ethernet cable out, so their use of twin cables may be considered by some to detract from the primary aim of simplicity. They did, however, not only bring the advantage that the adapter, complete with its status LEDs, were put to the desktop rather than being down on the floor at the mains socket as with the 401s, but they also had the further twin advantages of having a two metre mains cable (twice the length of the 401’s cable), plus the extension offered by the separate Ethernet cable itself. That meant you can more easily accommodate connection of the unit on the desktop, if that’s the primary aim.

Until recent developments, PowerLine adapters suffered from not only lower speed than WiFi but also interference from certain types of electrical gear that was located adjacent to the adapter. These days that’s largely a thing of the past, such have been the strides forward in development of these units.

Compatibility with every version of Windows from 98SE to Vista, plus Mac and Linux, may be attractive to you, as may the fact that you could confidently do without a WiFi connection altogether and perhaps save yourself the anxiety of having to sit all day being bombarded by radio waves. We won’t know the outcome of the enquiry into that scenario for some time. In the meantime, speaking for ourselves, we were very content to find that we could never stray out of signal range in some of the more remote parts of the building, though, of course, you can’t avoid the wiring that goes with the PowerLine HomePlug Adapters.

In conclusion

These devices just about compete with WiFi adapters in terms of cost-effectiveness. When you consider that, in round figures, you'd be shelling out around £50 for a WiFi adapter (ie for a computer not already WiFi equipped) the asking price of around £110 for a twin pack of PLA401s, or £60 for a single pack, does add up to a reasonable buy.

Notwithstanding the fact that the rather big adapters on the 401 units overlay adjacent power sockets, almost ensuring that you have to use multi-outlet power leads and make any adjacent sockets redundant, they are recommended. The 400s don't suffer from that problem, though the twin cabling may be considered to have it's downsides, depending on the layout of your computer desk.

For the beginner, the fact that networking with these units is so easy, and that they set themselves up automatically with network security settings, is all to the good; this essential final step isn't going to remain forgotten. Don't forget that you may have to factor in the cost of the router to which the first adapter has to be connected if you don't already have one.

 

Don Bradbury