the present invention relates to methods and arrangements to measure network performance . the method comprises the following steps : — transmitting via a communication network payload packets from a sending node to a receiving node . — generating at the sending node a send specification for each of at least one selected packet of the transmitted payload packets . — generating at the receiving node , a receive specification for each of at least one selected packet of the transmitted payload packets . — bringing together generated send specifications and generated receive specifications . — estimating network performance by utilizing corresponding specifications of the brought together specifications .