A method for performing a performance measurement of a link connecting a first node and a second node of a communication network, said method comprising: a) before starting a performance measurement, providing said first node and said second node with measurement mode information comprising at least a measurement start time (T start) and a packet transmission rate; b) at said measurement start time (T start), generating and transmitting a packet flow from said first node to said second node, said packet flow comprising a plurality of packets (Pk) whose transmission times are determined by said measurement start time (T start) and said packet transmission rate, said generating and transmitting comprising generating and transmitting first packets during first block periods (T, T, T,...) and second packets during second block periods ((T, T, T,...) which alternate in time with said first block periods (T, T, T,...); c) at a block period (T(k)) of said first block periods (T, T, T,...) or second block periods ((T, T, T,...), while said packet flow is received at said second node, updating a variable (OWDcum(i), OWDmax(i), OWDmin(i), CDth(i)) indicative of a behaviour of said packet flow during said block period (T(k)), by using said measurement mode information and detected information on reception of said packet flow; and d) at a subsequent block period (T(k+1)) of said first block periods (T, T, T,...) or second block periods ((T, T, T,...), calculating a parameter (OWDav(k), OWDmax(k), OWDmin(k), %OWDth(k)) indicative of a performance of said packet flow during said block period (T(k)) using a value reached by said variable (OWDcum(i), OWDmax(i), OWDmin(i), CDth(i)) at the end of said block period (T(k)). a) before starting a performance measurement, providing said first node and said second node with measurement mode information comprising at least a measurement start time (T start) and a packet transmission rate; b) at said measurement start time (T start), generating and transmitting a packet flow from said first node to said second node, said packet flow comprising a plurality of packets (Pk) whose transmission times are determined by said measurement start time (T start) and said packet transmission rate, said generating and transmitting comprising generating and transmitting first packets during first block periods (T, T, T,...) and second packets during second block periods ((T, T, T,...) which alternate in time with said first block periods (T, T, T,...); c) at a block period (T(k)) of said first block periods (T, T, T,...) or second block periods ((T, T, T,...), while said packet flow is received at said second node, updating a variable (OWDcum(i), OWDmax(i), OWDmin(i), CDth(i)) indicative of a behaviour of said packet flow during said block period (T(k)), by using said measurement mode information and detected information on reception of said packet flow; and d) at a subsequent block period (T(k+1)) of said first block periods (T, T, T,...) or second block periods ((T, T, T,...), calculating a parameter (OWDav(k), OWDmax(k), OWDmin(k), %OWDth(k)) indicative of a performance of said packet flow during said block period (T(k)) using a value reached by said variable (OWDcum(i), OWDmax(i), OWDmin(i), CDth(i)) at the end of said block period (T(k)).