A method for enabling a performance measurement on packet flow transmitted through a communication network. A marking value is periodically switched in the packets with a marking period Tm. The packet flow is then divided into blocks of duration Ts (synchronization period). Each synchronization period comprises an integer number of marking periods. Two or more measurement points on the path of the packet flow may provide a performance parameter for each marking period and associate thereto a synchronization information generated based on their local clocks and relating to the synchronization period containing the marking period to which the performance parameter relates; and a sequence information indicating the marking period's position within the synchronization period. A management server may identify performance parameters provided by different measurement points and relating to a same marking period based on the synchronization information and the sequence information.