Abstract: The call controlling or managing server (A) comprises a telephone platform database (B) containing detailed data (C) on calls, data (D) on data traffic associated to calls and data (E) referred to users and to their associated IP devices, with respective information including IP address, telephone number, etc. The system comprises a graphic user interface (GUI) which presents: a first interface (J) for configuring the corporate sites, a second interface (K) for configuring numbering plans and a third interface (L) for configuring voice and data billing plans. A module (M) for classifying calls divides calls into typologies according to the entered numbering plans. An additional value module (N) is used to determine call value, i.e. for calculating respective costs of both voice calls and data calls given the entered billing plans. Finally, reference O indicates one or more modules for creating generic and/or detailed reports which can be accessed by the system administrator.