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Why white-space Wi-Fi won't wash

Ofcom and others are promoting white-space radio as the next big thing in Wi-Fi. That's not just technically wrong, it also risks the future of the technology itself
Written by Rupert Goodwins, Contributor

What is Wi-Fi? It's low-power, short-distance, unlicensed broadband wireless networking. And white-space radio? Low-power, longer-distance, unlicensed broadband or narrowband wireless networking. They're similar, in the way cats and dogs are similar in the fur, legs, head and tail departments but, crucially, they are not the same.

Wi-Fi is more than a network. It's a set of standards that do a particular job and live under a brand — and both standards and brand are important. When Ofcom uses Wi-Fi to describe its concept of white-space wireless networking, when it has neither the standards or fulfils the brand, it runs the risk of setting expectations that may not be met. That damages the chances of white space being the success it deserves to be. Like selling a house cat for guard duties, disappointment is on the cards.

A painful past

It is easy to forget how painful, mysterious and frustrating wireless networking used to be. At first, there were no standards: if you wanted to use an IBM wireless LAN, you used it with IBM wireless LAN parts.

It wouldn't interoperate with, say NCR's WaveLAN. And although WaveLAN was taken up by other companies and then developed into 802.11 and thus Wi-Fi, the years before that happened were painful indeed. WaveLAN card from company X did not speak unto WaveLAN card from company Y.

But with the Wi-Fi consortium, the rules became simple: if you wanted to have Wi-Fi on your box, it had to talk to other Wi-Fi devices, and as many of them as possible. Mostly, that worked. That made wireless networking a true consumer technology.

It doesn't mean that all wireless networking has to be Wi-Fi. Saying that white-space radio is 'Wi-Fi on steroids' or 'Extended Wi-Fi' and using a Wi-Fi logo to promote white-space radio is not actually fair to either party.

White-space radio

For example, unlike with Wi-Fi, there are a whole set of unresolved issues around the idea of a portable white-space device. To avoid interfering with other licensed services on the same frequencies, white-space radios have to know where they are and then find out from a central database what frequencies and power levels are safe. Those details haven't been worked out yet for stuff that moves about: if and when they are, they'll still set restrictions.

Wi-Fi has no knowledge of or need for the geolocation that's hard-wired into white space, and isn't limited by it. White space, on the other hand, has far more potential for low-speed, low-power, long-range connections, whereas its high-speed modes only make sense where neither Wi-Fi nor cellular wireless data do the job.

Thus, white space will never be usable in exactly the same way as Wi-Fi is. Nor should we expect it to be. It has advantages and disadvantages of its own that will define what it's good for. That's what makes it worthwhile as an innovation.

It's not just that the chances of your 2014 mobile phone having white-space radio that works like Wi-Fi are slim to zero. The chances are higher that, if people associate white space with Wi-Fi, they'll be confused and expect something different. Hey, can I stream HD video across town with my Wi-Fi enabled phone? Will my existing Wi-Fi router work with 'white-space Wi-Fi'? Imagine fielding those support calls. Confusion and disappointment kill markets stone dead.

So, please, Ofcom and others, continue to promote the many good ideas and undoubted potential behind white-space radio. It's exciting technically, it advances the state-of-the-art in good, practical wireless, and it could lead to some revolutionary new products and services. It's a splendid example of how a regulator can actively create and promote important innovation.

Just be careful what you call it.


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