Service Model of the IVEF Service 3.3 Data Model of the IVEF Service 3.3.2 The Place of the IVEF Service ... Service Model of the IVEF Service 3.3 Data Model of the IVEF Service 3.3.2 The Place of the IVEF Service ... Service Model of the IVEF Service 3.6 Interfacing Model of the IVEF Service The IVEF Service refers to