White Spaces – why the resistance?

It’s an amazing idea. Radio signals at less than 1 GHz pass easily through buildings. TV broadcast signals are below 1 GHz so you can use an indoor antenna. Anywhere in the US about half the TV channels are idle, so why not use these empty channels (White Spaces) for wireless broadband Internet access? The FCC has been pushing this idea since 2004. The IEEE has a workgroup (802.22) hammering out the technical details, and some of the mightiest companies in the technosphere are banding together to make it happen.

Even the broadcasting industry sees the merit of this idea – in a letter to Senators Stevens and Inouye, David Donovan, the president of MSTV (the Association for Maximum Service Television) says:

Ensuring that the United States is a global leader in the provision of broadband services is a worthy goal. We believe this goal can be accomplished, especially in rural markets, without causing interference to new digital television receivers and converter boxes… Our desire is to find a solution that will bring broadband to underserved Americans while ensuring that consumers’ and broadcasters’ investments in the DTV transition are protected.

Did you spot the catch? The broadcasters are worried that unlicensed use of their spectrum will interfere with their broadcasts. The chief executives of Disney, News Corporation, NBC and CBS sent a letter to the FCC saying:

As you know, current proposals based on “sensing” to avoid interference could cause permanent damage to over-the-air digital television reception.

There are two main categories of issue here: technical and compliance. Both must function correctly to avoid the outcome feared by the broadcasters.

On the technical side, if technologies can be developed that effectively eliminate the potential for interference, and regulations can be crafted that require the use of such technologies, the broadcasters have nothing to fear. This technical issue is relatively easy to debate, and while the broadcasters may seem overly cautious to some, their position is reasonable:

It has taken nearly a decade for government and industry to deploy digital television across this nation. A rush to place millions of unlicensed devices in the TV band without extensive real-world testing should not undermine these efforts.

But technical issues yield to engineers in time, and we can confidently expect cognitive radio to work properly in the end. Credible proponents argue that it is working correctly already. The FCC tested devices from Microsoft and Philips in July 2007 expecting to close this issue with hard data, but in a catastrophic blunder one of the tested devices was defective and failed the tests, leaving the issue open. The broadcast industry seized on this mistake and used it to characterize the technology in general as unripe. But the technical argument will eventually yield to conclusive experimental results, showing that cognitive radio works, and that unlicensed use of this spectrum as proposed by the FCC will not interfere with TV broadcasts.

The compliance and enforcement issue is far tougher to resolve, but it is separate from the White Spaces issue, and should be debated separately. This issue is actually more important, since it concerns not only the TV broadcast frequencies but the utility of the entire radio spectrum in the US. If devices that transmit on radio frequencies are badly engineered, defective or designed in such a way that they don’t conform to the regulations, it is possible that they might interfere with legitmate uses. As things stand, there is no guarantee that this will not happen, since the enforcement arm of the FCC is weak. Michael Marcus, in his “Spectrum Talk” blog goes into this issue and proposes some actions.

SDK for iPhone

In a message signed by Steve Jobs, Apple announced that it will release an SDK for the iPhone in February.

This means that Adrian Cockroft was right when he said that Apple simply hadn’t had time to create an SDK for the initial release of the product. This was reported in an interesting Wired post.

How open will the iPhone be with the SDK? There are two kinds of open-ness associated with the iPhone, first the ability to load applications into the phone’s execution environment and run them, and second the ability for the phone to work on any GSM network (network unlocking).

The announcement says:

We want native third party applications on the iPhone, and we plan to have an SDK in developers’ hands in February. We are excited about creating a vibrant third party developer community around the iPhone and enabling hundreds of new applications for our users.

To reduce the risk of malware, Apple plans to require digital signing of some kind for the applications; this is a great idea provided that the process to get the signature isn’t too arduous.

It will be interesting to see how much of the system is exposed through the SDK. Nokia’s Symbian environment lets third parties take control of the telephone UI, so that they can implement handset clients for FMC. If the iPhone SDK provides the hooks to do this the iPhone would become useful in a dual-mode enterprise environment. But it is unlikely that the iPhone will soon be as enterprise-friendly as the Nokia ESeries phones, which have OMA-DM, and just-announced “Freeway” connection mangement.

As for the network unlocking, Apple is rumored to share in the service revenue stream that AT&T gleans from the iPhone, and is also rumored to have similar arrangements with its European network partners. If you could buy an iPhone and activate it on any network, Apple would miss some of this revenue. This means Apple is motivated to make sure that every iPhone sold is tied to a service plan from which it gets revenue. But once that activation has occurred, and the customer has committed to a long term service agreement, both AT&T and Apple will get monthly service revenues whether the phone is used on that network or not. On the other hand, Apple will be shipping an unlocked phone in France, since French law limits locking of phones to networks. Whether this will have any effect on unlocking policy in other countries is to be seen. Unlocked French iPhones will presumably flood eBay as soon as they are released, and class action suits in the USA may force AT&T to unlock iPhones on demand, or within 90 days of purchase (as they do other phones) or at the end of the service agreement (two years).