r plane topology database is a separate structural element in the MSS. Its main purpose is to store user plane topology information (see Figure 4.34) and, when requested, to deliver this information to the user plane control application. The user plane control application uses topology data to route the user plane to the proper destination. There are two kinds of data in the topology database. data records for user plane destinations (UPDs); data records for interconnections. The operator can enter the actual network configuration to the database. The related source data templates are UPD creation, MGW full-meshed subnetwork and MGW interconnection. A group of MGWs that is controlled by the MSS must be filled in the UPD creation form. In the case of a meshed network interconnection between those MGWs, the MGW identity (i.e. MGW name and ID) has to be properly defined in the MGW full-meshed subnetwork and MGW interconnection forms. Creating User Plane Analysis in the MSS The user plane analysis and its components are created in the MSS. The analysis consists of several subanalyses, which can be linked to the chain and to different kinds of results. There are six phases in the user plane analysis and as every phase has its own attributes, every phase has its own results too. For example, when the originating MSS has determined which terminating MGW to connect its MGW (originating) to, the succeeding user plane destination (SUPD) parameters of the user plane analysis in the originating MSS will identify the user plane destination for the outgoing route. User Plane Detailed Planning BICC / SIP H.248 H.248 Figure 4.35 Digit analysis and routing in the MSS Creating other Analyses in the MSS The related source data templates and the MML commands required for creating other analyses are shown as follows: origin analysis; preanalysis and results; extended preanalysis and results; end of selection analysis; end of selection attribute analysis and results; routing attribute analysis and results. digits analysis; charging an