The Global Functional Plane (GFP) is a functional layer in the IN layer model
al Plane (DFP) and the Service Plane (SP). The GFP layer has a global approach and abstracts intelligent networks (IN) to a single instance on which all services are realized with the Service Independent Building Blocks
(SIB). The Global Functional Plane is specified in ITU Recommendation Q.1201 "Principles of Intelligent Network Architecture".