Dynamic constraint satisfaction for feature interaction

As telecommunications service features become more plentiful, service providers are faced with the increasingly difficult task of providing consistent and high-quality service. A stumbling block along the path towards making available large numbers of complex and potentially highly customised features are the unwanted or unforeseen behaviour of these features when operating together. This problem, known as the feature interaction problem, is only compounded by the heterogeneity of service providers, service platforms, and feature implementations. Presented in this paper is a constraint-based approach for performing avoidance, detection, and resolution of these feature interactions in a run-time telecommunications environment, such as an intelligent network. This constraint representation centres around a framework for call resources, permitting structured access to each of the aspects of call functionality, allowing features to remain modular. The representation is further enhanced, beyond the basic finite state feature processes, by the maintenance of context information. The resulting call session information keeps track of information such as how a feature is being used, by whom it was invoked and when, and what other callers and features are currently involved.