There might be something wrong with the plot http://www.strangeloopnetworks.com/assets/images/AverageLoad... , since it looks like a unimodal gamma, beta or log-normal type distribution, but the seconds are on the vertical axis. Did a random ordering of sites along the horizontal axis just happen to end up looking like a gamma distribution? Highly unlikely.
So what does the plot mean?
Looks like nonsense.