We discuss the requirements, a model and protocol for the out-channel interaction for PCS in Intelligent Networks. As PCS can utilize the DSSI function (i.e. location update, authentication), it is reasonable to consider a model and protocol of the interaction for PCS as well as DSSI. To obtain the model/protocol, two types of interactions, call-related and call-unrelated, are considered. It is necessary to enhance the Basic Call State Model (BCSM) for the former, and to introduce a state model similar to BCSM for the latter, which represents association management and component exchange between a user and the network. The authentication function allocation for the dominant traffic, location update, is discussed based on the model and protocol, and this can co-exist with the proposed generic model and protocol.

Currently, new telecommunication services that are planned to be offered require the addition of functions to switching systems. This is because service specification translation processes and service execution processes are implemented in a dedicated fashion for each new service. The service-, vendor-, network-independent Intelligent Network (IN) architecture is expected to play an important role in introducing new services rapidly and efficiently. This paper proposes the service creation and execution domain concept for IN. This concept defines the scope for interactions and general rules accesses between services, functions, and data. Based on the identified functional requirements for IN service creation and execution processes, this paper discusses the roles of the proposed service creation and execution domain concept. It also discusses the hierarchical domain types in relation to the identified IN participants, and it identifies the general rules for the proposed domain concept, considering the IN studies in the CCITT, especially the IN Conceptual Model and IN Application Programming Interfaces.