Most of the half-a-million Radiohead fans who raced to download the band’s new album “In Rainbows” on Thursday were not in fact using the public internet to do so, writes Maija Palmer in London.

Instead, the music files were transferred to computers over a private network run by PacketExchange, a UK-based technology company. Radiohead is the latest content owner to look for an alternative to the public internet to deliver its wares.

"If this album was sent over the public internet, it would have bounced back and forth, significantly slowing down the download. This can have serious implications on the overall user experience and jeopardise Radiohead’s reputation," says Kieron O’Brien, chief executive of PacketExchange.

"A recent survey we commissioned shows that, on average, users wait no longer than 10 seconds to get the content they want, so speed is absolutely fundamental."

Radiohead’s decision to pay PacketExchange to speed deliveries of its album are a further sign of the public internet struggling to cope with delivering new media services such as TV, video and music. (Contracts of this kind are usually worth tens of thousands of dollars per month.)

The public internet was designed for tasks such as sending e-mail or surfing web pages, where speed is not critical. However, it can struggle to deliver services such as streamed TV content.

Internet service providers in the UK, for example, have complained that services such as the BBC iPlayer, which offer video on demand over the internet, could overwhelm their networks.

A number of companies have been looking at alternatives. Internet companies, including Google, Yahoo, Microsoft and social networking sites Piczo and Bebo, have turned to PacketExchange to help speed their content to users.