The Panasonic BL-PA100KT jumps on the Ethernet over mains bandwagon but goes against the grain by offering a product based on a proprietary format. For this reason, it's not compatible with Homeplug products such as Devolo's Homeplug AV kit.

As with other Ethernet over mains products, you simply connect one plug into your router or modem and the other anywhere else in the house. Data is then transferred over the mains network in your house. It's a much neater alternative to lengthy Ethernet cables and more reliable than wireless connections.

The BL-PA100KT kit consists of one master plug that you attach to the router and an additional plug to get you started. You can add more plugs to create a wider network, up to a maximum of 16.

All the units use standard figure-of-eight power leads plugged into sleek looking rectangular boxes. Similar devices, such as Netgear's HDX101, cram all the technology into one big plug - this is a neater solution, but has the drawback of the bulky plug not always fitting into mains sockets near the floor, for example. Panasonic's approach is far more flexible.

The BL-PA100KT really is plug-and-play since there's no software included to change settings. 128bit AES encryption is setup as standard and a button on top of each plug, combined with a master/terminal switch, allows you select which plug is attached to the router and which plugs will be placed around the house.

Three lights on the front of the boxes diagnose any problems and will flash red if there's no connectivity. A quick tap on the setup button provides information the signal strength on that particular plug; one bar for less than 10mbits/sec, two bars for less than 30mbits/sec while three bars indicate more than 30mbits/sec.

The plugs are rated at 190Mbits/sec but this figure, like all maximum theoretical speeds, is wildly misleading.

In our labs (a somewhat noisy environment) we got two bars strength and a set of inconsistent speeds ranging from 9.7Mbits/sec in close proximity, to 6.7Mbits/sec over a longer distance. This was using the same testing technique to our recent draft-n wireless routers group test and our results indicate it's no substitute for an Ethernet connection, which will consistently score 93Mbits/sec.

However, during home testing in a relatively noise-free home environment we found speeds of 28.6Mbits/sec over a short distance and 25Mbits/sec when the plugs were split one floor apart. This makes streaming high definition content possible; an 802.11g Wifi network will struggle with HD since you can expect no more than 18-20Mbits/sec on average.

Data transfers were far more reliable than what we've seen with top end wireless equipment, but not quite as good as the Netgear HDX101 we recently reviewed. But it's important to remember the speeds are dependant on factors such as the quality of mains wiring in your house and other appliances on the mains.

If you've already got some Homeplug kit on your network, you're unlikely to want to introduce this Panasonic alternative into the fold due to their lack of Homeplug compliance. However, if you're happy setting up a total Panasonic mains networking environment, they're reasonably priced and perform adequately.