A method for measuring the resident time of a probe message in at least a network node comprised within a network path, the probe message provided with a Time-To-Live value, the method including steps of: registering the receive timestamp of the probe message; writing the receive timestamp into a dedicated field within the received probe message; checking the Time-To-Live value of the probe message; decrementing the Time-To-Live value by one if the Time-To-Live value is not null, and if the Time-To-Live value is equal to one, then: registering the transmit timestamp of the probe message; computing the probe message resident time within the network node by subtracting the registered receive timestamp to the registered transmit timestamp; writing the computed resident time into a field within the probe message; and changing the value of a flag within the received probe message in order to protect the resident time from being over written by subsequent action on the probe message.