... duration of the ringing phase is calculatedas the difference between the answer time (i.e., the instantwhen the callee answers) and the signaling complete time (i.e., the instant when the communication ... Pattavina and A. Parini, “Modelling voice call interarrivaland holding time distributions in mobile network,” in Pro-ceedings of the 19th International Te letraffic Congress (ITC ’05),Beijing, China, ... finishes). The conversation duration is the difference between the charging-end time (i.e., the instant when the billing account stops) and the answer time. In our analysis, the setup time is not includedin...