Timothy B. Lee
May 6th, 2014
If you’re the customer of a major American internet provider, you might have been noticing it’s not very reliable lately. If so, there’s a pretty good chance that a graph like this is the reason:
These graphs comes from Level 3, one of the world’s largest providers of “transit,” or long-distance internet connectivity. The graph on the left shows the level of congestion between Level 3 and a large American ISP in the Dallas area. In the middle of the night, the connection is less than half-full and everything works fine. But during peak hours, the connection is saturated. That produces the graph on the right, which shows the packet loss rate. When the loss rate is high, thousands of Dallas-area consumers are having difficulty using bandwidth-heavy applications like Netflix, Skype, or YouTube (though to be clear, Level 3 doesn’t say what specific kind of traffic was being carried over this link).
This isn’t how these graphs are supposed to look. Level 3 swaps traffic with 51 other large networks, known as peers. For 45 of those networks, the utilization graph looks more like this: