Performance measurement in a packet-switched communication network

A method is disclosed for performing a performance measurement on a packet flow transmitted along a path through a packet switched communication network. At least two measurement points implemented on the path calculate a sampling signature for each packet of the flow by applying a hash function to a mask of bits of the packet, and identify a sub-flow of measurement samples as those packets whose sampling signatures are equal to a certain value H*. The measurement points then provide measurement parameters for the measurement samples, which are used for providing performance measurement for the whole packet flow. Tailoring the length of the sampling signature allows the sampling rate to be statistically controlled so as to balance the risk of reception sequence errors between measurement samples and the computational effort on one hand, and the accuracy of the measurements provided on the other hand.