[TinyRedLeaf]

File-sharers forced to play fair

BBC News (31 Aug 2007): Researchers have found a way to enforce good manners on file-sharing networks by treating bandwidth as a currency.

The team has created a peer-to-peer system called Tribler in which selfless sharers earn faster upload and download speeds but leechers are penalised. The technology is being assessed by a European broadcasting body looking at ways of piping TV across the net.

Tribler has also been used to turn Sony's PlayStation 3 into a video-sharing device.

While file-sharing networks are good ways to help lots of people get hold of large files often they have far more people taking from the system than they do giving. Peer-to-peer networks can become sluggish if too many users download content without sharing with others.

Using bandwidth as a kind of currency helps to encourage better habits said Dr Johan Pouwelse, an assistant professor at Delft University of Technology, Amsterdam and co-creator of Tribler.

Dr Pouwelse has been working with associate professor David Parkes from Harvard University to add an accounting system to Tribler to encourage users to upload as often as they download.

"In our model your TV would use "TV watching minutes", our form of P2P currency, to download content," said Dr Pouwelse. "The TV would connect directly to the internet and provide video on demand in HDTV quality. After you watch a program on TV, the system would automatically share this program during the night with other people, until your 'TV watching minutes' credit is healthy again," he said.

"If we get this right, it would mean quite a change in the TV business," said Dr Pouwelse.

Using bandwidth as a currency can remove some of the problems seen in file-sharing systems such as BitTorrent, said Dr Parkes. "In peer-to-peer, I can build up credit by offering upload capacity and then use the credit for download in the future," he said.

"There is still a balance, but the balance is on the order of days rather than seconds and this time-shifting can be welfare enhancing, said Dr Parkes.