ustrates this evolution. It has three different network management systems at sub-network level (radio access, core network and legacy GSM network). A simple management structure of a GPRS network is shown in Figure 16.8. TM Internal Architecture in the Layered Dimension The architecture can be presented as divided in three layers as shown in Figure 16.9. The presentation layer takes care of the interface with the operator providing a user-friendly environment and easy network-handling capabilities. Internet presentation technologies are used, with Java included to support application portability on different IT platforms. The service layer is responsible for the real interaction between manager and agents through the scheme command issuing or managed object parameters setting, and events or statistics collection. SNMP, CORBA and C++ have been explained before. The information layer performs the administration of the manager and NE's manage- ment information base. SQL (simple query language) is a typical database administrator. LDAP handles the secure access to the databases and to the system and JDBC (Java data base connectivity) handles databases via Java coding. Network management system integration Network level Sub-network RANOS CN-OSS level WCDMA Network radio radio elements network access nework level For WCDMA/UMTS operators CN-OSS together with RANOS will form the management system Figure 16.7 Example of management structure of a 3G system (RANOS: radio network opera- tion system) Telecom Management - Operations Operation & maintenance of GPRS network O&M system Network management Configuration Performance Fault handling MSC/VLR SMS-G/IW MSC ISP/Corporate network Backbone PTM-SC network Traffic path BGw = Billing gateway Signaling path PTM = Point-to-multipoint Management network path Figure 16.8 Management structure of a GPRS system, also showing some different types of management processes as a bridge to next part of this chapter Presentation access layer Launch interface CORBA http, telnet Service COR