200Mbit 'instant mains net' kits on sale soon

Instant home networks using mains wiring and rated at 200Mbits/sec will be available in Britain before summer – but come with the predictable tussle over standards.

Netgear will ship 200Mbits/sec adapters, costing €120, that provide an Ethernet port by simply plugging them into the mains. They use a chip from the Spanish company DS2.

Products using chips conforming to the latest HomePlug AV specification from the HomePlug Powerline Alliance (HPPA), a consortium of interested companies, will also go on sale rated at 200Mbits/sec.

Like wireless networks though, rated speeds are always higher than real throughput because of network overheads. C Scott Willy, of HPPA member Spidcom, admitted that the real HomePlug AV throughput was likely to be around 70Mbits/sec.

AMD used Netgear’s version at Cebit to demonstrate its Live technology – its answer to Intel’s Viiv entertainment platform. 

Dave Everitt, European products and platforms manager at AMD, said the company has tried both home plug technologies and the Netgear/DS2 device was much faster. 'We’ve been getting 147Mbits/sec,' he said.

Panasonic is also going to push power-over-mains kits using its own technology, High-Definition Power Line Communication, or HD-PLC. This is rated at 190Mbits/sec.

Akhiro Sobue, manager of Panasonic’s power-line communication planning office, said the company would make the technology price competitive with Wifi – though the two technologies are complementary rather than rivals.

But Panasonic has retreated a little from last year when it talked of putting HD-PLC modules into consumer electronics devices like TVs and hi-fi equipment. This, it has to be said, would be convenient: devices would be networked simply by plugging them in.

Sobue said a module would add $40 to $60 to the price of a device and there were a couple of third-party PLC-enabled personal-video recorders on his stand.

But there is no point doing this it unless other linked devices are also using HD-PLC. Scott Willy reckoned Panasonic had backed off because big players like Sony were backing HomePlug.

In fact there are those who fear that data over the mains is a little too good to be true.

It is shoving radio-frequency signals down unshielded wires, which means it is acting as an RF transmitter. Some frequencies, like those used by radio amateurs, are ‘notched out’ to avoid interference; but not those used by civil aircraft, though military channels are protected.

The fear is that the cumulative effect of thousands of installations in cities could interfere with aircraft communication.

Frédéric Onado, Spidcom’s vice president of marketing, said this would not happen because the power used is to small and all the various installations would be using different frequencies and orientations.

The Civil Aviation Authority has said it is monitoring the situation.