Abstract: 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 said first terminal and said 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 two subsets 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 said stream passing in transit through the network equipment.