eRAN Performance KPI Overview (Retainability KPIs)

Retainability KPIs

VoIP Call Drop Rate

• This KPI can be used to evaluate the call drop rate of the VoIP service in a cell or a cluster. The call drop rate is calculated by monitoring the VoIP ERAB abnormal release rate. Each E-RAB is associated with the QoS information.
• E-RAB includes both the E-RAB radio bearer and corresponding S1 bearer. Any abnormal release on either bearer causes call drop and therefore is counted into the call drop rate. The abnormal release is identified by the Cause IE (Information Element) defined in Reference.

Service Drop Rate (All)

This KPI can be used to evaluate the call drop rate of all services in a cell or a cluster, including VoIP service.

E-RAB Release

Normal release

Released with the normal procedure, the statistic is based on each QCI index    

Abnormal release:

• Considered as service(call) drop, the statistic can be based on different release cause and each QCI index
• Possible causes:

EPC failure

Radio link failure

Handover failure

Transport failure

Network congestion

 Abnormal Release



 Normal Release