TCP path sharing detection

A number of methods have been proposed to obtain the information of a TCP path without the help of routers and control protocols. All of the active methods proposed in the past consider such a path a linear as a time invariant system in order to ensure the observation obtained at the receiver is a convolution of the input added by senders although the assumption is hardly held in practice. To overcome the problem, we in this paper propose a method to detect the number of TCP flows sharing a part of their paths. The proposed method drops the assumption of liner time invariant by taking into account the events occurred at transport layer. It requires each flow periodically adds a UDP train to the same destination that results in a periodic turbulence in terms of delay. Using the information, we are able to distinguish the frequencies of the UDP trains from end to end delays and accomplish the task. Simulation is conducted to confirm the proposed method.