One of the key factors driving new applications and wider adoption of the Internet has been the increasing bandwidth available to the public. For example, the World Wide Web started to take off among ordinary computer users in the mid-1990s once images were added to pages, and this only became feasible when dial-up modem speeds had increased sufficiently to allow graphics to appear after a few seconds' downloading.

Another instance of how access speed sparked a dramatic shift and rise in online use occurred at the end of the 1990s, when it became possible to download digital music files in a reasonable time, thanks to the rediscovery of an older compression technology, MP3 - strictly speaking MPEG Audio Layer-3. Taking advantage of this, millions of young people started to swap tracks from CDs through Napster, and a huge new class of users were drawn in to the world of the Internet.

Of course, unlike the addition of graphics to Web pages, the swapping of copyrighted material was problematic. Napster was stymied by the lawsuits it garnered, but once the genie was out - in this case, online access to an effectively complete song catalogue - it was not going to be bottled up again. Indeed, the record industry's efforts to destroy Napster and obdurate refusal to offer legitimate music downloads themselves simply meant that users turned to other forms of file- swapping, notably Kazaa, whose P2P architecture makes it harder to control than Napster's centralised servers did.

Napster is back, in a respectable, subscription-based form. Meanwhile, the online music throne has been usurped by Apple's powerful iTunes/iPod combination. Apple has recently launched its service in Europe to an eager audience, but it faces a range of competitors there, and not only from Napster, which started up in the UK in May 2004.

One of the most innovative music download services is OD2's SonicSelector, launched the day before Apple's European iTunes, and sold through various partners in the four countries where it is currently available. In addition to offering the options pioneered by Apple - the ability to download a track to several computers and players, and to burn CDs - SonicSelector adds an interesting feature. For just a penny a track, users can listen once to a complete, streamed version of the song. This is a very different approach from subscription models or those based on paying to acquire a track permanently, and effectively implements a micropayment system - something that has signally failed to take off more generally in ecommerce.

Where Apple employs the AAC compression standard, both SonicSelector and Napster are built around Microsoft's Windows Media format. Microsoft has recently announced an updated version of its digital rights management (DRM) system, which allows various licensing models, including rental, where files are acquired for a predefined time period. Apple uses a different DRM system called FairPlay.

The availability of multiple, incompatible DRM solutions is one problem that needs to be solved for the online music market to flourish. A more profound issue is whether the DRM approach is the best way of achieving an equitable and workable solution for all the parties involved - consumers, creators and distributors. Since it is always possible to circumvent DRM schemes - if only by recording the analogue output - groups in the US and Europe have suggested that a better idea might be flat-rate levies.

Sorting out content control and remuneration will soon become even more urgent. Currently, the attention is focused on songs rather than films because full-length DVD files are still too big to be swapped over the Internet by most users. But as the fledgling world of Internet2, the next-generation version of the Net that has a 10 Gigabit/s backbone and aims to provide 100 Megabit/s to the desktop, already indicates, it is only a matter of time - and bandwidth - before Hollywood will have to face the (digital) music too.

Glyn Moody welcomes your comments.