Today is the day that Google opens up its database of US White Space spectrum, starting the mandatory 45-day trial in readiness to start giving away another thing everyone else is charging for.

The trial is public, and ready to go live, and will map out which of the TV broadcast frequencies aren't being used in any specific location, and which are thus available for short-range devices to use, licence-free, under the FCC's White Space regulations.

Eventually, superfast networks might use the spectrum, perhaps even Google itself will build a White Space network, but for the moment Google is merely one of several firms given permission to compile and test White Spaces databases by the FCC to keep the process fair.

Spectrum Bridge and Telcordia completed their trials late last year and there are another 10 companies approved to run databases - including Microsoft - but Google is interesting because it's one of the biggest brands involved and has previously suggested that, unlike the competition, it won't charge for access to its data.

Not that anyone is planning to charge the end users, but companies making White Space hardware will need to sign a deal with one of the 13 databases licensed by the FCC. When a White Space device is switched on, it checks its location and contacts the appropriate database to find a frequency in which it can operate, without knocking out local TV broadcasts or wireless microphone users (assuming the latter have registered with the FCC), but as all the databases get their information from the same source (the FCC) Google's future competition is working hard to justify their bills.

Spectrum Bridge, for example, is pushing into the UK and elsewhere in the hope that international coverage will prove important to manufacturers who want to sell kit all over the place. It will also use feedback from the kit to improve the database, and try to help devices avoid each other too, making for better data than Google will be giving away.

Not that Google has committed giving away the data, not yet, but the company is well placed to profit from knowing the location and usage of every White Space device, and when a single, central, database was mooted Google offered to run that for free.

But the single master was rejected for a model which requires all the databases to talk to each other. This means wireless microphone users can register with any of the 13 and see their information replicated across the network, hopefully.

That also forms part of the testing, which will last until 17 April at least (the FCC can ask for extended testing if anything goes awry).

With two databases already running, Americans can use White Space kit today, but making the devices takes time so there aren't many deployments just yet. The licence-free technology can offer 16Mbps connections with a range of 10km and a battery life of 14 years, though not all at the same time, so it should be seriously disruptive - which is why Google is so keen to be a part of it. ®