Requesting Usage-Monitoring in ESM

Gx Usage-Monitoring is activated explicitly from the PCRF via CCA-I, CCA-U or RAR. It is triggered via the Usage-Monitoring-Information AVP along with the event-trigger = usage-report (33). The Usage-Monitoring-Information AVP contains the following AVPs:

Usage-Monitoring-Information::= < AVP Header: 1067 >
                                  [ Monitoring-Key ]
                            0,2   [ Granted-Service-Unit ]
                            0,2   [ Used-Service-Unit ]
                                  [ Usage-Monitoring-Level ]
                                  [ Usage-Monitoring-Report ]
                                  [ Usage-Monitoring-Support ]

There could be multiple instances of Usage-Monitoring-Information AVP present in a single CCA or RAR messages. For example, simultaneous Usage-Monitoring for IP-CAN session level, credit-category level or pcc rule level can be requested.

Usage-Monitoring-Level for IP-CAN session is set to SESSION_LEVEL (0)

Usage-Monitoring-Level for category-map is set to PCC_RULE_LEVEL (1)

Usage-Monitoring-Level for PCC rules is set to PCC_RULE_LEVEL (1)