Global internet speeds could be about to take a severe hit. An astronomic rise in P2P bittorrent traffic is anticipated next week when file-swappers share DivX-encoded files of new US shows such as Heroes and Prison Break.

A massive 4.2 petabytes of data could be downloaded next week as a result. That's the equivalent of a billion MP3s or 890,400 DVD-quality movies.

Why now? Because the new autumn or 'fall' TV season is just about to kick off in the US. TV show-swapping is rampant across the internet and bittorrent traffic looks certain to sky rocket as thousands of people start downloading the brand new shows.

Tech-savvy UK TV fans don't want to wait to see the latest episodes of their favourite US TV series. But the burden of this extra web traffic could leave ISPs struggling to cope with the load.

Will ISPs feel the burn?

The numbers don't make pretty reading. People downloading TV shows using bittorrent networks could add 4.2 petabytes a week to global internet traffic. In other words: imagine over 4.2 million gigabytes of TV show data being piped across the internet every seven days.

Astonishingly, that works out to be 6.9GB of data downloaded every single second. These are fairly modest estimates too, so the true numbers could well be a lot higher.

One show recorded in standard definition amounts to roughly 350MB, and each episode is downloaded on average around 200,000 times on average. Some are uploaded in 720p high-definition and so have much bigger file sizes, while others are not downloaded as many times as others. So it's reasonable to assume that these factors even each other out.

Roughly 60 torrented US shows per week amounts to 21GB of information. This is then downloaded, on average, 200,000 times, which uses over 4.2 million gigabytes of bandwidth.

Midweek traffic to skyrocket

Much of this traffic will go through UK servers, more people in the UK use bittorrent than any other country. And the figures don't even include those who download TV shows via other P2P networks such as eDonkey - if they did they would most likely be higher.

The autumn TV season in the US sees the re-launch of smash-hit shows such as Prison Break, Desperate Housewives, Heroes, House and Grey's Anatomy. And new shows such as Bionic Woman and The Sarah Connor Chronicles, (based on the Terminator movies) look set to only add to the congestion.