rough several mechanisms, including agents installed on infrastruc- ture, synthetic monitoring, logs of activity, sniffers, and real-user monitoring. In the past network management mainly consisted of monitoring whether devices were up or down; today performance management has become a crucial part of the IT team's role that 176 SIP Trunking brings about a host of challenges-especially for large organizations. The Operation and Maintenance function must be capable of performing the following functions: Event/alarm management Configuration management Performance management Security management Fault management These functions are discussed in the following sections. Event/Alarm Management Alarms need to be presented to the Network Management System (NMS) platform, via software programs and tools for easy presentation and interpretation, for easy mainte- nance and to locate faults of all managed elements of the SBC system. Events shall be logged for future inspection and remedial actions. Configuration Management The Operating and Management (O&M) module must provide real-time configuration access to manage software loading, version tracking, and support for addition, deletion, and change of network element parameters. The O&M module needs to support soft- ware installation and upgrade. Performance Management The O&M module must provide tools (such as Simple Network Management Protocol (SNMP), command-line interface, XML, COBRA, and SO on) for the collection of statistics and call and session information into a logging file for the SBC. The data must be viewed using tabular or graphical reports on the Graphical User Interface (GUI) terminal. Security Management The O&M module must provide password and login access to the system to prevent any unauthorized access to the system. It needs to have the capability of providing at least two-level access profiles with provision for field-definable of the privileges for each. Fault Management The O&M module must provide the capability to query and change device states and pr