FremgangsmÕte og innretning for Õ mÕle kvaliteten i et nett for overföring av digitale eller analoge signaler

A method for measuring a quality of a line network using an in-service non-intrusive measurement device monitoring of live traffic measurement process includes determining reference values of parameters of the in-service non-intrusive measurement process for a connection over at least a part of the line network and storing the determined reference values in a memory so that the determined reference values are allocated to the part of the line network. The part of the line network is monitored using the in-service non-intrusive measurement process so as to generate measured values of the parameters of the in-service non-intrusive measurement process. The measured values are compared with the respective stored determined reference values so that correspondences with and divergences from the stored determined reference values are recognizable and capable of being evaluated with regard to a quality of transmission.