Sharing of movies, music and computer software on the internet in Japan has surged in the last 15 months to hit an all-time high, according to the results of a survey published Friday.

As of September this year 9.6 per cent of internet users in Japan were using file-sharing software compared with just 3.5 per cent in June 2006, while the average number of files downloaded stood at 481 in September against 194 in the middle of last year, the survey said. Of those 481 files just under half were audio files at 211. An average 183 video files were downloaded per user: 34.7 image files, 33.2 document files and 14.2 computer software files.

The results were gathered through a web-based questionnaire to which 20,301 responses were received, said the three organisations that co-sponsored the research: the Recording Industry Association of Japan, the Japan and International Motion Picture Copyright Association, and the Association of Copyright for Computer Software.

The broad availability of domestic broadband connections, many of which are 100Mbps (bits per second) fibre-optic internet lines, is certainly making file-sharing easier with 96 per cent of sharers on broadband.

The Winny software was found to be most popular with a 27 per cent share. In its heyday, Winny was used by more than half of all file sharers in Japan, but has steadily seen its market share drop with a number of high-profile cases in which viruses on the network have opened users' hard drives to the internet. Documents including police investigation materials, training manuals for Japan's Self Defence Forces, data related to nuclear power plants and information including the names of sex crime victims have all found their way into the public domain via Winny, according to local news reports.

Those high-profile leaks seem to be having a minor deterrent effect on users. In the latest survey 31 per cent of people who have given up file sharing reported it was due to concerns over personal documents leaking onto the network whereas in the 2006 survey that reason was cited by only 26 per cent of file-sharing quitters.

Popular applications

Other popular applications include Limewire at 18.8 per cent, WinMX at 15 per cent, Cabos at 13.1 per cent and Share at 11 per cent. BitTorrent, which is widely used in North America and Europe, ranked sixth in the Japanese survey with a 7.4 per cent share.

The popularity of Winny was underlined by a companion survey that was carried out by crawling the file-sharing networks. It found 264,000 nodes on the Winny network and a total of 4.8 million files available, while the Share network was made up of 200,000 nodes and has 549,000 files available.

The results highlight the losing battle that many Japanese content providers have been fighting against online file sharing and the posting of copyrighted content on sites such as YouTube.

Earlier this year content providers complained to YouTube about the situation and were partially responsible for pushing the Google subsidiary towards the development of a content fingerprinting system that, when it is in full operation, should help the identification and removal of copyrighted content that has been unofficially uploaded.

It's not just the legal battle that is being lost but the technological one too.

The switch to digital TV in Japan saw TV broadcasters attempt to take back control of their content with the introduction of a rights-managed environment for TV shows. Almost all TV shows are broadcast with a copy-once restriction that means consumers can make a single recording of a TV show onto a hard-disk drive or DVD disc with copy-protection. Conventional discs cannot be used because they lack support for the rights management system and once the recording has been made the original file can be moved between media but not copied.

Nevertheless the restrictions have not stopped some users, and digital high-definition copies of Japanese TV shows can easily be found on file-sharing networks. Faced with this failure and collective criticisms from users who want to make personal copies of favourite TV shows, and the industry is about to modify the system to allow for limited copying of content.