A data packet transmission network comprises a stream of packets of data sent by a first terminal passes in transit through at least one network equipment with which there is associated a stream measurement unit; wherein the first terminal and the measurement unit are connected to a collection unit. The measurement method comprising the following steps: the first terminal sends a specific stream of packets, each having a different determined size, the sizes being such that in a set of r packets, r being a positive integer less than or equal to the number of packets of the stream, there are not any two subsets of the set of r packets comprising the same number of packets and having the same cumulative total size; the measurement unit analyzes at least one packet and at most r packets of the stream passing in transit through the network equipment.