End-to-End Detection of ISP Traffic Shaping Using Active and Passive Methods
The authors present end-to-end measurement methods for the detection of traffic shaping. Traffic shaping is typically implemented using token buckets, allowing a maximum burst of traffic to be serviced at the peak capacity of the link, while any remaining traffic is serviced at a lower shaping rate. First, the authors develop an active end-to-end detection mechanism, referred to as ShaperProbe, that can infer whether a particular path is subject to traffic shaping, and in that case, estimate the shaper characteristics. Second, they analyze results from a large-scale deployment of ShaperProbe on M-Lab over the last few months, detecting traffic shaping in several major ISPs. Third, we modify the ShaperProbe detection algorithm so that it can be applied passively on the traffic of any TCP-based application.