Real time round trip delay time measurement methodology between remote VoIP Operators

The paper deals with real time round trip measurement methodology. In contrast with probe-based methods, the new methodology tries to use an existing VoIP Operator infrastructure without any hardware or software installation into the infrastructure. The measurement is based on packet payload comparison and timestamp evaluation. The results of the measurement can be used as an external monitoring tool of VoIP infrastructure between VoIP Operators or for call admission control functions.