A modeling and protocol for the out-channel user interaction in intelligent network

Intelligent network capability set 2 (IN CS-2) has been discussed in the ITU-T to add new capabilities on the IN CS-1 refinement. One of these capabilities, the out-channel user interaction capability exists within the scope of IN CS-2. We discuss the requirements, a model and a protocol for the out-channel user interaction (e.g. Q.932 on DSS1) in an intelligent network (IN). Considering that the existing supplementary service for DSS1 may be implemented as an IN supported service, it is necessary to enhance the basic call state model (BCSM) for bearer related interaction, and to introduce a state model similar to the BCSM for bearer unrelated interaction that represents the association management and the component exchange between a user and the network. The application of the model to the other protocol stack is also mentioned. We assume that the signaling system considered for the CS-2 time frame is N-ISDN