1. A method for detecting correlation between an input channel and an output channel, comprising: generating packet data by observing packets sent and received through the input and output channels for a window of time; generating, by a processor, a model of inter-arrival time of packets received on the input channel and packets sent on the output channel; generating, by the processor, a model of predecessor waiting time for packets received on the input channel; determining a difference between the model of inter-arrival time and the model of predecessor waiting time; and determining that the input and output channels are correlated if the difference is greater than a threshold.