5.5 OSI Functional Model The OSI functional model specifies that network management functionality can be grouped under five main categories (see Figure 5.10). They are FCAPS short for fault, configuration, accounting, performance, and security. The ITU-T intro- duced FCAPS as part of M.3400 for a telecommunication management network (TMN). The ISO used this concept for management of data networks by intro- ducing it as part of OSI management model. These five functional areas form the basis of all network management systems for both data and telecommunications. Refer to chapter on FCAPS for a detailed explanation of the functional areas. 5.6 OAM The OAM stands for operation, administration and maintenance. The OA&M and OAM&P are words popular in the telecom management world for network management functions. The five function areas are covered as part of OAM, hence it is quite common to refer to network management systems as OA&M systems. When the NMS involves a lot of provisioning functions, then the NMS solution is referred to as OAM&P where P stands for provisioning. It can be seen that the SNMP functional model adopts the concept of OAM (see Figure 5.11). The ITU-T defined OAM in its document M.3020 and 3GPP uses the term OAM in its documents on network management standards for specific networks. OSI functional model Configuration Fault Performance Accounting Security management management management management management Figure 5.10 OSI functional model. SNMP functional model Operation Administration Security management management management Figure 5.11 SNMP functional model. Fundamentals of EMS, NMS and OSS/BSS Operations is the control center that coordinates actions between administration, maintenance, and provisioning. Administration deals with designing the under- lying network, processing orders, assigning addresses, tracking usage, account- ing, and other activities associated with network administration. Maintenance is to monitor, diagnose, and repair problem scenarios in the network. Provisioning han