Summary

This ITU-T Recommendation contains the Unified Functional Methodology (UFM), superseding the existing ITU-T Q.65 (06/97), describing a common functional architecture for providing services and addressing signalling requirements for service implementation. The overall method for deriving switching and signalling Recommendations for ISDN services, consisting of three stages, is described in ITU-T I.130. The method has been generalized beyond ISDN to include services provided in and among networks of various types. The UFM combines the traditional approach of the 1988 version of this Recommendation with some of the approaches traditionally used in the Intelligent Network (IN) description method. The detailed method for deriving the Stage 2 portion of these Recommendations is described in this Recommendation. The main text of this Recommendation presents background information on the unified functional methodology, the steps of the method, the conventions used in description techniques, and guidelines for usage.