The internet is a becoming a mature technology

During 2004 the amount of net traffic travelling on backbone cables between nations grew by 104%, reported the consultancy Telegeography.

By contrast in 2005 the growth slumped to a less stellar 49%.

Telegeography said the change could be the result of a global slowdown in the numbers of people signing up for high-speed net services.

Big numbers

Just how fast net traffic has grown over the last few years can be seen via statistics from the London Internet Exchange (Linx), where more than 150 net service firms swap data between each other.

In a little over a year the amount of traffic flowing across Linx has risen from approximately 30 gigabits per second to more than 67 Gbit/s. In 2000 it was barely hitting 5 Gbit/s, the equivalent of a DVD film every 10 seconds.

Alan Mauldin, senior research analyst, said that in any other field annual growth of 49% would be incredible. It was only the fact that the net had grown so fast, so quickly for so long that now made such a figure less impressive.

"But it's still fairly robust growth," he told the BBC News website.

Growth rates in some territories was staying high, said Mr Mauldin, at 76% in Asia and 70% in Latin American but even these were down on 2004.

Currently the amount of traffic flowing between nations is approximately one terabit per second. If growth rates hold up this is likely to hit three terabits per second by 2008.

Much of the growth over the last few years has come about because of the rise in the popularity of file-sharing that encourages people to swap and share large media files, said Mr Mauldin.

In general, he said, the net was maturing in the sense that the numbers of those going online was slowing and those already online were using it as much as they were likely to.

Another sign, he said, was a stabilisation in the prices for net backbone access which fell sharply before 2005.

Mr Mauldin was keen to point out that the measurements it was taking were not a snapshot of all net traffic. This was because Telegeography does not count the amount of data flowing over cables within national boundaries which, he said, was likely to be at least as large cross-border traffic.

However, he said, international net traffic was a good indicator of the general direction and strength of net growth.

Telegeography can produce figures for 2005 because its annual count runs from April to April.