IP volume will double every two years from 2007 to 2012, and will soon require us to express web traffic volumes as exabytes (one billion gigabytes), says a new report by Cisco Systems.

Cisco say web traffic is growing at an annual rate of 46 per cent, increasing largely due to streaming HD video and web 2.0 applications, as well as the increasing use of social networking sites – a phenomenon which the report calls "visual networking".

Apparently, soon after 2012 we'll have to start measuring in zettabytes (one thousand billion gigabytes).

According to the report, video now accounts for approximately one quarter of all consumer internet traffic, growing from 12 per cent in 2006 to 22 per cent in 2007, and due to reach 32 per cent by the end of this year.

However, that figure doesn't include video data exchanged through P2P file sharing, which now carries 600 petabytes (that's 600 million gigabytes) more per month than this time last year – equivalent to 150 million more DVDs crossing the network every month.

The report is based on Cisco's own predictions, taking analysis from several market research firms.