Overview Of The Call Trace Function

Overview of the Call Trace function Introduction to call trace The call trace feature enhances fault management, optimization and security. The feature can also be used to locate stolen or defective GSM equipment. A network can be optimized by analyzing call trace data that is collected from a call made by a designated mobile as it travels through the network. Network operators can also use this feature to determine why calls are being dropped due to RF loss. The call trace function enables an operator to trace the activities of various network elements (BSS, SITE, CELL, RTF) for events associated with a particular subscriber or equipment, or selected cells. An operator at an OMC, MSC or BSS can create a trace if the Call trace flow control attribute is disabled, (setting this up is described in Installation and Configuration: GSM System Configuration (68P02901W17). Each trace has certain criteria associated with it, which the operator is required to specify to create a trace. For example, which calls are to be added to the trace log. From the OMC an operator can: * Create a trace. An operator can only create a call trace if the Call Trace function has been enabled in the User Profile List. * Delete a trace. An operator can only create a call trace if the Call Trace flow control attribute is disabled. * *

View the trace criteria for active, deactivated, and completed traces. View the trace records associated with each trace.

* Perform other actions such as terminating a trace on a particular cell, or preventing an active trace from triggering any more new invoked instances by permanently deactivating the trace. NOTE

Only one trace can be active on a specific call at any instant.

The user should delete and recreate trace criteria if LCFs are added or reset. Care should be taken when creating traces to prevent the OML becoming flooded. MSC initiated IMSI and IMEI call trace is detailed in Installation and Configuration: GSM System Configuration (68P02901W17). NOTE The call trace function will only work with BSS software loads at GSR4 or later. Call trace categories Traces can be in one of the three categories:

1. Active traces. These traces can still invoke new instances. 2. Deactivated traces. These are traces which have been deactivated by the operator at the BSS or OMC, deactivated internally by the BSS, or the current time is outside the triggering period for the trace. NOTE Active and deactivated traces have call trace managed objects in the MIB (and at the BSS). 3. Completed traces. These are terminated traces, managed objects for them do not exist at the BSS They are included so that the operator has access to the trace record for completed traces.