During the next year or so, telecommunications in Europe will face one of its most crucial decision points, as the fate of the 2.6GHz band is decided.

"It's a once in a lifetime event," says Simon Bates of UK regulator Ofcom. "It's the most significant allocation of spectrum for the next ten years or so. It's very important that we make the right choices on it."

"There won't be another band like it," agrees Roger Horlock of WiMax provider Metranet Communications in Brighton. "It's the sexiest band going - it's right on the edge of the sweet spot."

What's so good about it?
The 2.6GHz band is often referred to as the "IMT-2000 expansion band" or the "3G expansion band". When the original 3G spectrum was allocated, 3G services were expected to grow so fast that the operators would soon need more spectrum. The 2.6GHz band was earmarked for more 3G services.

To put it in perspective, the 2.6GHz band is 190MHz wide, while the 3G licences that were auctioned in 2000 for a total of £22.5 billion only totalled 140MHz.

It's great spectrum, because it can penetrate buildings, and long distances of air, and carry data well. It also overlaps with one of the main frequency bands being used by WiMax developers, and is available in the US.

WiMax proponents would like the EU to allow their technology in this band, helping to create a uniform market for WiMax equipment.

What should we do with it?
EU policy can take as long to turn round as an oil tanker. Despite the slow build-out of 3G services, and the fact that Europe's mobile operators clearly do not need more 3G bandwidth any time soon, some EU member states were apparently blithely ready to carry on with the allocation for the 3G technologies, IMT-2000.

That would have given Europe's mobile operators the chance to sit on prime spectrum and hold back the spread of rival WiMax technologies. If this were to happen, it would be a prime example of how tying licences to a particular technology can hamper progress.

Fortunately, a different message is gathering momentum. In the UK, the regulator, Ofcom, has decided to make future licences tradeable, and technology-neutral, so the holders of those licences can use any appropriate technology.

"At this point, the 3G expansion band is a European issue," says Simon Bates, of Ofcom. "We are engaged in discussions with European neighbours, to determine how this very important piece of spectrum should be allocated.

"We are campaigning very strongly for Europe to adopt a technology-neutral approach," he said. "Any technology that is used must not interfere with IMT-2000, however, it should not be limited to IMT-2000."

What gives most benefit?
Bates believes that the overall view of the other European regulators has swung towards technology-neutral licences, despite previously-entrenched positions. The process is currently open to consultation from interested parties, and that consultation period has just been extended to September.

"We are likely to see a conclusion [to the Europe-level debate] in December," says Bates. "Clearly, the more UK industry response we can get, the more weight our argument would have."

The EU consultation is based on the economic impact of not adopting a common position on this. The regulators want to see uniformity, so that revenue can flow across Europe, and operators of whatever kind of network can benefit from a unified market.

There's probably no panic about the technology side: "The Radio Spectrum Committee [the EU's deciding body] is keen to see spectrum allocations made in a technology neutral way, says Amit Nagpal, senior consultant at Analysys Consulting.

Once the technology issue is decided, Ofcom would prefer the spectrum to be allocated by auction, which may be something of a worry, as the mobile operators have deep pockets.

"If you look at the prices of spectrum, licences for fixed wireless access [where WiMax vendors are coming from] cost three orders of magnitude less than those for mobile use," said Nagpal. "Two and a bit orders of magnitude, if you factor out the 3G auctions."

So mobile operators may have a hundred to a thousand times as much money to spend as their WiMax rivals.

What about WiMax?
"We'd be minded to allow WiMax as well as any other technology, as long as it did not interfere with IMT-2000," says Bates, who wants an auction to determine fair access. "We're talking about a blank page, because the [mobile] WiMax standard is not yet agreed."

WiMax vendors really want this spectrum for the economies of scale: "There's going to be lots of 2.6GHz hardware," says Horlock. "It allows the elusive indoor install, which wireless ISPs need for cheap deployment."

"If we don't get this band for WiMax use, then the most progressive technology around will not get exploited as it could," warns Horlock. "Operators are trying to send WiMax up the spectrum for use as backhaul. If it gets this spectrum, it can shift far more data than 3G."

Or how about citizen's WiMax?But Horlock wants to go further. With his involvement in public-sector WiMax, he'd like to see some spectrum allocated exclusively for the public sector, and argues the case for "citizen's WiMax" here.

"How many local authorities would like to be running their own telecoms service?" he asks. "They alone are a massive market. There will be WiMax on phones, and in the meantime we can use Wi-Fi to distribute it."

It's an interesting idea, but analysts are sceptical. Nagpal points out that Horlock's request would make sense if there were clear benefits to the country as a whole that could not be provided by the market: "It's more likely to be done on the model of the operator buying spectrum."

Whichever way it goes, the 2.6GHz allocation, when it happens, will be big news.