New route to the Net

Access the Net by plugging into the nearest electric power socket? An idea discarded as unrealisable, may soon become reality. Anand Parthasarathy looks at exciting recent developments which are poised to culminate in the first practical realization - only weeks away - of Powerline Internet.

TWO INDUSTRIAL towns in Germany's Rhine valley are engaged in a curious race that will finish in a few weeks. In Essen in the Ruhr district, Germany's largest power utility, Rheinische Westfaelische Energie (RWE) is busy readying a few thousand homes for the first ever commercial demonstration of Powerline Internet - access to the global Net through the domestic electric power socket. Its technology partner in this exciting experiment is the Swedish group Ascom.

A few hundred kilometres to the South, at Mannheim, another German electricity provider, MVV, has tied up with Israeli telecom developer Main.net Communication Ltd, to set up an identical facility for 3000 homes.

Both these initiatives were announced at the recently concluded international IT show, CeBit 2001 at Hannover, ending years of doubt and industry skepticism, about sending data content over electric supply lines.

That may explain why the first commercial offerings of powerline Internet are coming from European providers - less susceptible than their American counterparts to the unsubtle resistance of major Internet providers committed to current delivery mechanisms like dial-up telephone, Cable TV links and direct-to-home satellite.

The logic for pushing any such technology is inexorable: the world over, the number of people who possess a telephone or Cable TV connection are a tiny fraction of those who have a electricity in their homes.

This is particularly so in India, where a telephone or a television set is still a luxury unaffordable by the broad mass of population, even though their homes may be electrified. If Internet ``flowed'' through the electric lines, it would see a major shift in the digital divide separating the information haves from the have-nots, and make a reality of the national goal of ``IT For All by 2008'' set by the central government 3 years ago.

Indeed, in a crude form, the basic technology of sending other information on the back of the household electric wiring has been with us for some years: you can buy ``wireless'' intercom sets in pairs for about Rs 500. You plug one set into a 220 volts AC mains socket and the other into a socket in another room - and you have a two station voice intercom.

If the two electric sockets are in the same phase line, they could be in different buildings, up to a kilometre apart- and you could still carry on a reasonable conversation. If voice can travel on top of the electric line, why not data? If someone at the power distribution point of the utility, feeds Internet connectivity, there is no reason why any customer cannot access it by simply tapping into a light socket. That is the basis of Powerline; but there have been problems:

At the utility end, you would need to convert Internet data signals into frequencies that would ride over the electric cable without too much loss. At the user end, one would need a special power socket modem to separate the data from the electricity.

A more serious problem has hitherto bugged all efforts to install a reliable powerline Internet system: the high levels of noise including radio frequency (RF) interference on most electric lines. You know what happens to the picture on the TV screen when someone next door switches on a mixie. This is precisely the problem that faced powerline data carrier developers: how to prevent heavy data losses when heavy noise makers are connected to the supply lines.

The German power companies and their R&D partners must have somehow overcome this technological challenge before announcing their services.

They may be the first - but they are not alone. A consortium called HomePlug Power Alliance (HPA) was formed in the US, a year ago by leading computer-and-communication companies including Cisco, 3 Com, Intel, Hewlett Packard, Motorola, Texas Instruments, Panasonic and Sharp to promote powerline networking and arrive at a common technical standard for related equipment. In January 2001, HPA completed its provisional specification ``Home Powerline Networking 1.0'', and this is due to be formally released in June this year.HPA has chosen as its baseline technology, the work of a small company called Intellon.

Its proprietary circuitry overcomes the noise problem by what it calls ``adaptive frequency domain technology'' - in other words, it adapts itself to the prevailing signal-to-noise ratio and avoids the use of noisy or unusable channels.

It also uses ``forward error correcting'' codes to anticipate possible noise limitations. HPA's Intellon-backed technology promises networking in the average home, using the domestic electric grids, that is at least as good as ethernet. Unfortunately, like most other technological advances, Powerline too, is hampered by lack of unity in the IT industry: HPA is not the only consortium. Another group based in Europe, called the Consumer Electronics Association (CEA) that includes Sony and Thomson is working on its own standards.

It is backed by the technology created by a company called Inari, a spin-off from Novell, the network people. Homeplug and CEA are currently talking to each other and hopefully they will decide not to work at cross purposes, killing the commercial possibility of a fledgling technology even before it is born.

Meanwhile, HomePlug has been carrying out on-site demonstration tests in 500 households around the world and expects that its member companies will release powerline network products to a common specification before the end of this year.

The main attraction to the consumer of these powerline net options ( other than the obvious one of not needing a telephone or cable connection) is that it is inherently capable of the broad bandwidths required to carry streaming video. While they initially spoke of 10 megabits per second as an achievable bandwidth on powerlines, no one is quite sure what the imminent German launches will achieve.

It also remains to be seen how affordable (or otherwise) powerline networking is. An AFP report from CeBit last week, suggested that the RWE/Ascom service would be priced at 49 Marks (Rs 1000) for every 250 MB of download. It also suggested that the speeds would be 30 times faster than the average speed achievable by ISDN phone- which would make it about 3-4 MBPS rather than 10 MBPS as thought earlier.

As the technology finds its feet and the market grows, all these figures - cost and speed -are likely to change rapidly - in opposite directions.

If Powerline emerges as a viable proposition, it will be the biggest breakthrough in the short history of the Internet, expanding beyond our wildest imaginings, its capacity to link and bind a troubled world. Give it to us, guys! We're waiting - and hoping!

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Section  : Science & Tech
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