A merged inline measurement method for capacity and available bandwidth

Abstract. We have proposed a new TCP version, called ImTCP (Inline measure-ment TCP), in [1]. The ImTCP sender adjusts the transmission intervals of data packets, and then utilizes the arrival intervals of ACK packets for the available bandwidth estimation. This type of active measurement in a TCP connection (in-line measurement) is preferred because it delivers measurement results that are as accurate as active measurement, even though no extra probe traffic is injected into the network. In the present research, we combine a new capacity measurement function with the currently used measurement method to enable simultaneous measurement of both capacity and available bandwidth in ImTCP. The capacity measurement algorithm is essentially based on the packet pair technique, but also consider the estimated available bandwidth values for data filtering or data cal-culation, so that this algorithm promises better measurement results than current packet-pair-based measurement algorithms. The capacity of an end-to-end network path is the maximum possible throughput tha