Basic call state model in an integrated IN/B-ISDN architecture

摘要

The integration of the intelligent network and B-ISDN offers a cost effective and flexible way to provide advanced services in public ATM networks in the near/medium term perspective. New modelling concepts in the IN architecture must be defined to support this integration. The main enhancements with respect to traditional IN has been the introduction of the session model within the service switching function (SSF), as a way to coordinate a set of different calls/connections in a service instance. Also the "SCP initiated call" concept has been exploited, allowing the service logic to build the connection topology as required by the different services. These new concepts have an impact within the IN call control function (CCF) at the level of the basic call state model. This article introduces the main aspects of the proposed IN/B-ISDN functional architecture, then the call modelling aspects are analysed in detail, with particular focus on the characteristics of the SCP initiated call.