Netgear HDX101 200Mbps powerline Ethernet adaptor

HD-ready wired networking via your home's power ports

I used two HDX101 units to connect a MacBook Pro and a Sony Vaio notebook between upstairs and downstairs rooms in my apartment. Powerline Ethernet adaptor suppliers warn against using multi-socket boards, but I had to and so, I suspect, will many other users. Avoid boards with surge-protection circuitry - that's the killer, I'm told. For testing, I used a simple two-socket extension cable with nothing plugged into the second socket.

I first used the open source network testing tool iperf to measure the link's TCP and UDP available bandwidths and got 56Mbps and 59.4Mbps, respectively. That compares to the 50.6Mbps and 59.4Mbps I recorded for the Devolo units over the same stretch of mains cabling. It's worth noting, perhaps, that when monitoring network usage with Windows Task Manager, the Devolo box produced a smoother chart than the Netgear.

Using the open source media playback and streaming application VLC, I was able to stream a 1080i HD video in MPEG 2 from the PC to the Mac with no trouble at all. There was clearly sufficient bandwidth to send the same video simultaneously from the Mac to the PC, although playback on the PC was very juddery because its GPU and CPU lack the power to decode the image data smoothly, not for bandwidth limitations.

While streaming the video to the Mac, I also measured the remaining available TCP bandwidth using iperf. So while Devolo's old 85Mbps adaptors, which I reviewed early last year, can smoothly transmit the HD stream, running iperf alongside it caused some picture break-up and yielded an available bandwidth figure of just 3.7Mbps.

The HDX101 pair continued to stream the HD content smoothly while iperf was running, with the measurement tool reporting there was 37.9Mbps of 'spare' bandwidth - enough for a second HD stream, and you might even get a third going if your own link's particularly good.

Netgear bundles the HDX101s with a configuration utility that allows you to adjust the adaptors' quality-of-service (QoS) settings. I got the above results with UDP traffic - the protocol most commonly used for streaming video data - prioritised. Setting the adaptors to prioritise TCP traffic - internet data essentially - the available TCP bandwidth went up to 54.7Mbps, but the HD playback began to get jerky. Turning off QoS, did not affect video playback and yielded a TCP bandwidth of 47.3Mbps.

Measuring powerline Ethernet bandwidth is a tricky business, of course. The capacity you get can vary according to which power socket you use, what else is connected and the overall quality of your wiring. But my tests suggest HDX101s will support multiple HD streams and provide enough bandwidth to share an internet connection and for multi-player gaming.

Verdict

Netgear's HDX101 is a solid powerline adaptor, but there are a couple of points to consider before buying one. I wouldn't hesitate to recommend it for performance, but there's the little matter of its incompatibility with other so-called 200Mbps products - if you want more units, you'll have to buy HDX101s if you want them to talk to each other. It's also quite a chunky unit, and it does suffer from a much slower connection initiation speed than its rivals. On the plus side they're about £20 cheaper than, say, Devolo's equivalent units. ®