ISPs in losing battle against P2P:

Increasingly peer-to-peer (P2P) software, which allows surfers to share music and video files, is dodging the defences of internet service providers.

It is becoming technically harder and harder to win the battle against file-sharing, said Sandvine, a firm that provides equipment to manage networks.

"The range of P2P defences available to service providers has suddenly become very limited," said Marc Morin, Chief Technology Officer at Sandvine.

"Managing the way this generation of P2P application impacts the networks requires techniques that are nimble enough to facilitate easy re-engineering," he said.

All traffic to a network goes through so-called ports and in the past P2P services have been assigned to a particular port.

Now developers of file-sharing services have redesigned the applications to use random ports.

This port-hopping renders traditional blocking methods ineffective or even obsolete, said Sandvine. [BBC]