A report from a network management firm called Arbor Networks has said that peer-to-peer traffic on the Web is falling rapidly. The company, which is used by more than 70% of the world's top ISPs, says that streaming video is replacing it, along with downloads from sites like RapidShare and MegaUpload.

"Globally P2P is declining and it is declining quickly", said Arbor Networks' chief scientist, Craig Labovitz. The data to support the report comes from 110 different ISPs, on nearly 3000 routers, for a total of 264 exabytes of traffic. An exabyte is 1024 petabytes, or approximately five times the amount of data contained in every bit of printed material in the world.

P2P now accounts for about 18% of all traffic on the Web (when you look at packets). In 2007, P2P peaked at about 40% of all web traffic. Services like YouTube, Spotify, iPlayer, Hulu and Netflix now all allow legal access to the same content, in many cases significantly more easily than a P2P download.

For years, commentators predicted that it'd be the growth of legitimate services that would bring an end to piracy, rather than legislation and lawsuits from content providers. This data seems to support that conclusion, though correlation is not causation, so it's difficult to say whether that's true or not - more studies will be required.

Spotify has conducted a survey that says that 80% of its users fileshare less after signing up, but we'd be interested in hearing your experiences. Have you found yourself illegally downloading less in the last few years?