When DSL and cable first arrived, ISPs abandoned the per-hour dial-up access billing model for unlimited bandwidth at a flat rate fee. Recently, Comcast has come under fire for shaping its traffic (read: blocking) while maintaining its unlimited contract with users. Lawsuits have been threatened and the FCC has been stirred to comment. The issue at hand is the peer-to-peer file sharing networks. While their user bases account for a very small percentage of the total Internet audience, the traffic they generate is said to account for anywhere between 50 and 90 percent of all data.