The internet is falling! You may recently have read that it could soon be overwhelmed by an “exaflood” of streaming video, as people flock to YouTube and the BBC's iPlayer.

This is just the latest version of an idea that keeps reappearing in different guises. In 1995 Robert Metcalfe, an American networking guru, predicted that the internet would soon collapse. It didn't, and Metcalfe duly ate his words, after liquidising them in a blender. More recently there have been claims that spam and viruses will bring down the internet.

This doesn't worry Jonathan Zittrain. In The Future of the Internet he claims that it is in danger in a more subtle way: its culture of innovation is under threat and we will all be the poorer for it. What makes the internet so valuable, says Zittrain, a professor of internet governance at Oxford University, is its “generative” nature - a handy term that encapsulates its open, anarchic and innovative essence.

He contrasts the modern, vibrant internet with the sterile corporate networks and online services (such as AOL and CompuServe) that came before it. These generative properties have given rise to new kinds of software (such as file-sharing and internet-telephony programs), and new websites and online communities (from Wikipedia to Facebook). But generativity has drawbacks. In particular, the creative anarchy of the internet has led to security problems such as spam and viruses. And some people just want to take advantage of the new things it can offer (music downloads and cheap phone calls, say) without messing around.

The result is the rise of “appliances” that are designed to do one thing well, but are limited compared with PCs. These include video-games consoles, internet-phone handsets, iPods, smartphones and locked-down web terminals. They can all connect to the internet and do things that could be previously done only on PCs. They are not prone to viruses. But, Zittrain worries, the spread of such “tethered appliances” endangers the internet's innovative culture.

For one thing, it is not always possible to load new software onto them. That is what makes them secure. But they can often be remotely updated by the companies that make them, who can add and remove features as they see fit. This concentration indirectly grants greater power to governments, Zittrain warns, who may be lured by the prospect of “perfect enforcement” of copyright and other laws through technological means. Rather than switching from flexible but complex and insecure PCs to inflexible but simple and secure appliances, he says, we need to work out how to address the internet's drawbacks. He holds up Wikipedia, the free online encyclopaedia that anyone can edit, as a model. The very fact that this triumph of positive generativity has not descended into anarchy suggests that there are ways to control negative generativity. He suggests various means by which Wikipedia-like approaches can be transplanted to the internet's technical layers. “The puzzle of PC security is fundamentally the same as the puzzle of keeping Wikipedia honest and true,” he observes.

The trouble is that although the notion of generativity is elegant, Zittrain overstates the case that the internet is in peril. None of his examples of harm is terribly convincing. Just because I have an iPod and an Xbox does not mean I no longer use a PC; there are still just as many PCs out there to provide a platform for new ideas. It is not a clear-cut choice between PCs and tethered appliances; many will use both. Another objection is that generativity at the code level is not the only kind, as the success of Wikipedia, blogs and eBay demonstrates (and as Zittrain himself concedes). The internet is a wonderful way to spread new ideas, and not just in the form of new software. New content, communities and marketplaces have evolved, and none requires you to download insecure new software to your PC.

Zittrain insists that generativity at the code level is the most important kind, but it is not clear that this is really under threat. In the early days of home-computing, most enthusiasts learnt the essentials of programming. (Remember Basic?) As other uses such as word-processing and e-mail came along, computers became general-purpose tools, and sales went up. Did it matter that the proportion of users who actually learnt how to program declined? Of course not. As long as some people know how, most do not have to. And as long as there are hundreds of millions of PCs out there, innovation on the internet will continue. Despite Zittrain's concerns, the emergence of other, simpler internet-access devices alongside PCs seems unlikely to change that.

The Future of the Internet: And How to Stop It by Jonathan Zittrain
Allen Lane £20 pp352

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