The Recording Industry Association of America sent 75 letters of legal complaint to about 50 Internet service providers asking them to block access to OpenNap, an open-source version of Napster allegedly being run from ISPs' networks.
The letters, reportedly mailed Friday, mark the RIAA's first move against online copyright violators since winning a decision against Napster last month in a federal appeals court.
OpenNap lets users set themselves up as smaller versions of the Napster music-swapping service. The system creates a directory through which linked computers can search each other's hard drives for music files. OpenNap requires a reasonably powerful computer and above average modem capabilities.
