Netflix rates North American ISPs

Netflix made good on a promise and released data on which US Internet providers offer the best access to Netflix streaming content. The company's data puts it "in the unique position of having insight into the performance of hundreds of millions of long duration, high-definition video streams delivered over the Internet."

Netflix displays throughput from Netflix content delivery networks to subscriber homes. Netflix's best quality HD streams are encoded at 4,800Kbps, and it's clear that no ISPs can sustain this level of service across an entire movie. But "the higher the sustained average, the greater the throughput the client can achieve, and the greater the image quality over the duration of the play," says the company. In the US, Charter delivers the best performance over time (2,667Kbps average), with Comcast, Cox, and Time Warner Cable taking the next three spots. The disparity between the top and bottom ISPs is stark; Clearwire offers only about half the sustained throughput as Charter (as a wireless operator, this is expected), but wireline ISPs like Frontier and CenturyTel also perform poorly (both companies do have large rural footprints, however). Netflix has promised to update the charts monthly, which may exert at least a bit of pressure on ISPs who might be tempted to throttle or otherwise downgrade Netflix quality.