Radio Network Unavailability Rate -- LTE

Radio Network Unavailability Rate

Description

The Radio Network Unavailability Rate KPI indicates the percentage of time when cells in a radio network are unavailable. This KPI is used to evaluate the deterioration of network performance caused by unavailable cells on the radio network during busy hours.

Definition

The Radio Network Unavailability Rate KPI is defined in Table 1. This KPI is calculated based on the length of time all cell services are unavailable on the radio network.

Table 1 Radio Network Unavailability Rate

Name	Radio Network Unavailability Rate
Object	Radio network
Formula	RAN_Unavail_Rate = (ΣCellUnavailTime/(TheTotalNumberOfCellsInCluster x {SP} x 60)) x 100% NOTE: "SP" indicates the reporting period for counters in minutes.
Associated Counters	Radio Network Unavailability Rate =((L.Cell.Unavail.Dur.Sys + L.Cell.Unavail.Dur.Manual)/(Number of cells x {SP} x 60)) x 100% "SP" indicates the reporting period for counters in minutes.
Unit/Range	Percentage (%)

CSFB Success Rate Based Handover (LTE to CDMA2000)

Description

The CSFB Success Rate Based Handover (LTE to CDMA2000) KPI indicates the success rate of handover-based LTE-to-CDMA2000 CSFB.
The number of handover-based LTE-to-CDMA2000 CSFB attempts increases by 1 at point B as shown in Figure 1 after the eNodeB sends a Mobility From EUTRA Command message to the UE and performs CSFB to a CDMA2000 network. The number of successful handover-based LTE-to-CDMA2000 CSFB executions increases by 1 at point C, where the eNodeB receives a UE CONTEXT RELEASE COMMAND message from the MME after the UE successfully accesses the CDMA2000 network.

Definition

The CSFB Success Rate Based Handover (LTE to CDMA2000) KPI is defined in Table 1. The number of handover-based LTE-to-CDMA2000 CSFB attempts and the number of successful handover-based LTE-to-CDMA2000 CSFB executions are collected as described in Description.

Table 1 CSFB Success Rate Based Handover (LTE to CDMA2000)

Name	CSFB Success Rate Based Handover (LTE to CDMA2000)
Object	Cell or radio network
Formula	CSFB_L2C_BasedHO_SR = (CSFB_L2C_BasedHO_Success/CSFB_L2C_BasedHO_Attempt) x 100%
Associated Counters	CSFB Success Rate Based Handover(LTE to CDMA2000) =(L.IRATHO.E2C.CSFB.ExecSuccOut/L.IRATHO.E2C.CSFB.ExecAttOut) x 100%
Unit/Range	Percentage (%)

CSFB Success Rate Based Handover (LTE to TD-SCDMA)

Description

The CSFB Success Rate Based Handover (LTE to TD-SCDMA) KPI indicates the success rate of handover-based LTE-to-TD-SCDMA CSFB.
The number of handover-based LTE-to-TD-SCDMA CSFB attempts increases by 1 at point B as shown in Figure 1 after the eNodeB sends a Mobility From EUTRA Command message to the UE and performs CSFB to a TD-SCDMA network. The number of successful handover-based LTE-to-TD-SCDMA CSFB executions increases by 1 at point C, where the eNodeB receives a UE CONTEXT RELEASE COMMAND message from the MME after the UE successfully accesses the TD-SCDMA network.

Definition

The CSFB Success Rate Based Handover (LTE to TD-SCDMA) KPI is defined in Table 1. The number of handover-based LTE-to-TD-SCDMA CSFB attempts and the number of successful handover-based LTE-to-TD-SCDMA CSFB executions are collected as described in Description.

Table 1 CSFB Success Rate Based Handover (LTE to TD-SCDMA)

Name	CSFB Success Rate Based Handover (LTE to TD-SCDMA)
Object	Cell or radio network
Formula	CSFB_L2T_BasedHO_SR = (CSFB_L2T_BasedHO_Success/CSFB_L2T_BasedHO_Attempt) x 100%
Associated Counters	CSFB Success Rate Based Handover(LTE to TD-SCDMA) = (L.IRATHO.E2T.CSFB.ExecSuccOut/L.IRATHO.E2T.CSFB.ExecAttOut) x 100%
Unit/Range	Percentage (%)

CSFB Success Rate Based Handover (LTE to GSM)

Description

The CSFB Success Rate Based Handover (LTE to GSM) KPI indicates the success rate of handover-based LTE-to-GSM CSFB.
The number of handover-based LTE-to-GSM CSFB attempts increases by 1 at point B as shown in Figure 1 after the eNodeB sends a Mobility From EUTRA Command message to the UE and performs CSFB to a GSM network. The number of successful handover-based LTE-to-GSM CSFB executions increases by 1 at point C, where the eNodeB receives a UE CONTEXT RELEASE COMMAND message from the MME after the UE successfully accesses the GSM network.

Definition

The CSFB Success Rate Based Handover (LTE to GSM) KPI is defined in Table 1. The number of handover-based LTE-to-GSM CSFB attempts and the number of successful handover-based LTE-to-GSM CSFB executions are collected as described in Description.

Table 1 CSFB Success Rate Based Handover (LTE to GSM)

Name	CSFB Success Rate Based Handover (LTE to GSM)
Object	Cell or radio network
Formula	CSFB_L2G_BasedHO_SR = (CSFB_L2G_BasedHO_Success/CSFB_L2G_BasedHO_Attempt) x 100%
Associated Counters	CSFB Success Rate Based Handover(LTE to GSM) = (L.IRATHO.E2G.CSFB.ExecSuccOut/L.IRATHO.E2G.CSFB.ExecAttOut) x 100%
Unit/Range	Percentage (%)

CSFB Success Rate Based Handover (LTE to WCDMA)

 

Description

The CSFB Success Rate Based Handover (LTE to WCDMA) KPI indicates the success rate of handover-based LTE-to-WCDMA CSFB.
The number of handover-based LTE-to-WCDMA CSFB attempts increases by 1 at point B as shown in Figure 1 after the eNodeB sends a Mobility From EUTRA Command message to the UE and performs CSFB to a WCDMA network. The number of successful handover-based LTE-to-WCDMA CSFB executions increases by 1 at point C, where the eNodeB receives a UE CONTEXT RELEASE COMMAND message from the MME after the UE successfully accesses the WCDMA network.

Definition

The CSFB Success Rate Based Handover (LTE to WCDMA) KPI is defined in Table 1. The number of handover-based LTE-to-WCDMA CSFB attempts and the number of successful handover-based LTE-to-WCDMA CSFB executions are collected as described in Description.

Table 1 CSFB Success Rate Based Handover (LTE to WCDMA)

Name	CSFB Success Rate Based Handover (LTE to WCDMA)
Object	Cell or radio network
Formula	CSFB_L2W_BasedHO_SR = (CSFB_L2W_BasedHO_Success/CSFB_L2W_BasedHO_Attempt) x 100%
Associated Counters	CSFB Success Rate Based Handover(LTE to WCDMA) =(L.IRATHO.E2W.CSFB.ExecSuccOut/L.IRATHO.E2W.CSFB.ExecAttOut) x 100%
Unit/Range	Percentage (%)
Note	None

Average CPU Load -- LTE

Average CPU Load

Description

The Average CPU Load KPI indicates the CPU usage during busy hours.

Definition

The Average CPU Load KPI is defined in Table 1. The CPU load is calculated by averaging the CPU usage ratio during the measurement period.

Table 1 Average CPU Load

Name	Average CPU Load
Object	CPU
Formula	MeanCPUUtility
Associated Counters	Average CPU Load = VS.BBUBoard.CPULoad.Mean
Unit/Range	Percentage (%)

Uplink Preschedule Resource Block Occupied Rate --LTE

Uplink Preschedule Resource Block Occupied Rate

Description

The Uplink Preschedule Resource Block Occupied Rate KPI indicates the percentage of uplink RBs allocated to UEs for pre-scheduling. The Uplink Preschedule Resource Block Occupied Rate KPI can be used to evaluate the impact on uplink RB usage caused by pre-scheduling.
If pre-scheduling is enabled, when there are remaining uplink RBs in a cell, the eNodeB allocates uplink RBs to UEs that have not sent a bandwidth request to reduce the uplink service delay of these UEs.

Definition

The Uplink Preschedule Resource Block Occupied Rate KPI is defined in Table 1.

Table 1 Uplink Preschedule Resource Block Occupied Rate

Name	Uplink Preschedule Resource Block Occupied Rate
Object	Cell/Radio Network
Formula	PrescheduleRB_URUL = RB_PrescheduleUsedUL/RB_AvailableUL
Associated Counters	Uplink Preschedule Resource Block Occupied Rate= L.ChMeas.PRB.UL.PreSch.Used.Avg/L.ChMeas.PRB.UL.Avail
Unit/Range	Percentage (%)
Note	None

Resource Block Utilizing Rate -- LTE

Resource Block Utilizing Rate

Description

The Resource Block Utilizing Rate KPI consists of two sub-KPIs: the uplink resource block (RB) utilizing rate and downlink RB utilizing rate. These two sub-KPIs indicate the busy-hour DL and UL RB utilizing rates in each cell or radio network.

Definition

The uplink and downlink Resource Block Utilizing Rate KPIs are defined in Table 1.

Table 1 Resource Block Utilizing Rate

Name	Resource Block Utilizing Rate
Object	Cell or radio network
Formula	RB_URDL = (RB_UsedDL/RB_AvailableDL) x 100% RB_URUL = (RB_UsedUL/RB_AvailableUL) x 100%
Associated Counters	Downlink Resource Block Utilizing Rate =(L.ChMeas.PRB.DL.Used.Avg/L.ChMeas.PRB.DL.Avail) x 100% Uplink Resource Block Utilizing Rate =(L.ChMeas.PRB.UL.Used.Avg/L.ChMeas.PRB.UL.Avail) x 100%
Unit/Range	Percentage (%)
Note	None

Maximum User Number -- LTE

Maximum User Number

Description

The Maximum User Number KPI evaluates the maximum number of users in RRC_Connected mode of a cell in a certain period of time. This value is calculated based on samples. The eNodeB records the number of users in the cell to be sampled every second and then calculates the maximum value of these samples throughout the measurement period.

Definition

The Maximum User Number KPI is defined in Table 1. The formula is mapped to its corresponding counters.

Table 1 Maximum User Number

Name	Maximum User Number
Object	Cell or radio network
Formula	MaxUserNumber
Associated Counters	Maximum User Number = L.Traffic.User.Max
Unit/Range	NA
Note	None

Average User Number --LTE

Average User Number

Description

The Average User Number KPI indicates the average number of users in RRC_Connected mode in a cell. This value is calculated based on samples. The eNodeB records the number of users in the cell to be sampled every second and then calculates the average value of these samples throughout the measurement period.

Definition

The Average User Number KPI is defined in Table 1. The formula is mapped to its corresponding counters.

Table 1 Average User Number

Name	Average User Number
Object	Cell or radio network
Formula	AvgUserNumber
Associated Counters	Average User Number = L.Traffic.User.Avg
Unit/Range	NA
Note	None

Uplink Traffic Volume -- LTE

Uplink Traffic Volume

Description

Similar to the Downlink Traffic Volume KPI, the Uplink Traffic Volume KPI consists of ten sub-KPIs. One KPI corresponds to the total of traffic volume for DRBs, and the other nine correspond to nine QCIs. This set of sub-KPIs indicates a cell's uplink traffic volume. The sub-KPIs are measured at the PDCP layer and exclude the PDCP header.

Definition

The Uplink Traffic Volume KPIs are defined in Table 1 and include ten sub-KPIs. The formula for each KPI is mapped to its corresponding counter.

Table 1 Uplink Traffic Volume

Name	Uplink Traffic Volume
Object	Cell or radio network
Formula	ULTraffic Volume ULTraffic Volume_QCI_1 ULTraffic Volume_QCI_2 ULTraffic Volume_QCI_3 ULTraffic Volume_QCI_4 ULTraffic Volume_QCI_5 ULTraffic Volume_QCI_6 ULTraffic Volume_QCI_7 ULTraffic Volume_QCI_8 ULTraffic Volume_QCI_9
Associated Counters	Uplink Traffic Volume = L.Thrp.bits.UL Uplink Traffic Volume of QCIn = L.Thrp.bits.UL.QCI.n n = 1 to 9
Unit/Range	bit
Note	None

Downlink Traffic Volume -- LTE

Downlink Traffic Volume

Description

Similar to the Radio Bearers KPI, the Downlink Traffic Volume KPI consists of ten sub-KPIs. One KPI corresponds to the total DRB traffic volume, and the other nine correspond to nine QCIs. This set of sub-KPIs indicates the downlink traffic volume in a cell, which is measured at the PDCP layer and excludes the PDCP header.

Definition

The Downlink Traffic Volume KPIs are defined in Table 1 and include ten sub-KPIs. The formula for each KPI is mapped to its corresponding counter.

Table 1 Downlink Traffic Volume

Name	Downlink Traffic Volume
Object	Cell or radio network
Formula	DLTrafficVolume DLTrafficVolume_QCI_1 DLTrafficVolume_QCI_2 DLTrafficVolume_QCI_3 DLTrafficVolume_QCI_4 DLTrafficVolume_QCI_5 DLTrafficVolume_QCI_6 DLTrafficVolume_QCI_7 DLTrafficVolume_QCI_8 DLTrafficVolume_QCI_9
Associated Counters	Downlink Traffic Volume = L.Thrp.bits.DL Downlink Traffic Volume of QCIn = L.Thrp.bits.DL.QCI.n n = 1 to 9
Unit/Range	bit
Note	None

Radio Bearers -- LTE

Radio Bearers

Description

The Radio Bearers KPI consists of ten sub-KPIs. One KPI corresponds to the total of radio bearers and the other nine correspond to nine QCIs. This set of sub-KPIs indicates the average number of radio bearers in a cell or radio network. The radio bearer for each QCI is based on the number of active RRC connections for each QCI, according to the QCI defined in the QoS information.

Definition

The Radio Bearers KPIs are defined in Table 1 and include ten different sub-KPIs. The formula for each KPI is mapped to its corresponding counter.

Table 1 Radio Bearers

Name	Radio Bearers
Object	Cell or radio network
Formula	RadioBearers RadioBearers_QCI_1 RadioBearers_QCI_2 RadioBearers_QCI_3 RadioBearers_QCI_4 RadioBearers_QCI_5 RadioBearers_QCI_6 RadioBearers_QCI_7 RadioBearers_QCI_8 RadioBearers_QCI_9
Associated Counters	Radio Bearers =L.Traffic.DRB RadioBearers of QCIn = L.Traffic.DRB.QCI.n n = 1 to 9
Unit/Range	NA
Note	None

Inter-Frequency Handover Out Success Rate -- LTE

Inter-Frequency Handover Out Success Rate

Description

The Inter-Frequency Handover Out Success Rate KPI indicates the success rate of inter-frequency handovers (HOs) from the local cell to neighboring E-UTRAN cells. The measurement methods of the related counters are similar to those for intra-frequency HOs described in Intra-Frequency Handover Out Success Rate > Description. The only difference is that the source and target cells operate on different frequencies and both work in FDD or TDD mode.

Figure 1 and Figure 2 illustrate intra-eNodeB HOs, and the source and target cells operate on different frequencies. The source eNodeB counts the number of intra-eNodeB inter-frequency outgoing HO execution attempts in the source cell at point B and counts the number of successful intra-eNodeB inter-frequency HO executions in the source cell at point C. Figure 3, Figure 4, Figure 5, Figure 6, Figure 7, and Figure 8 illustrate inter-eNodeB HOs, and the source and target cells operate on different frequencies. The source eNodeB counts the number of inter-eNodeB inter-frequency outgoing HO execution attempts in the source cell at point B and counts the number of successful inter-eNodeB inter-frequency HO executions in the source cell at point C.
 

Definition

The Inter-Frequency Handover Out Success Rate KPI is defined in Table 1. Note that the number of outgoing HO execution attempts and the number of successful outgoing HO executions are collected based on the description in Description.

Table 1 Inter-Frequency Handover Out Success Rate

Name	Inter-Frequency Handover Out Success Rate
Object	Cell or radio network
Formula	InterFreqHOOut_SR = (InterFreqHOOutSuccess/InterFreqHOOutAttempt) x 100%
Associated Counters	Inter-Frequency Handover Out Success Rate = [(L.HHO.IntraeNB.InterFreq.ExecSuccOut + L.HHO.IntereNB.InterFreq.ExecSuccOut)/(L.HHO.IntraeNB.InterFreq.ExecAttOut + L.HHO.IntereNB.InterFreq.ExecAttOut)] x 100%
Unit	Percentage (%)
Note	None

Intra-Frequency Handover Out Success Rate -- LTE

Intra-Frequency Handover Out Success Rate

Description

The Intra-Frequency Handover Out Success Rate KPI indicates the success rate of intra-frequency handovers (HOs) from the local cell to neighboring E-UTRAN cells. The intra-frequency HOs are classified into intra- and inter-eNodeB HOs.

Intra-eNodeB Outgoing HO

Intra-eNodeB outgoing HOs can be further classified into HO with RRC connection reestablishment and HO without RRC connection reestablishment.

• Intra-eNodeB outgoing HO without RRC connection reestablishment
  Figure 1 illustrates an intra-eNodeB outgoing HO without RRC connection reestablishment, and the source and target cells operate at the same frequency. When the eNodeB sends an RRC Connection Reconfiguration message containing the handover command to the UE, the eNodeB counts the number of intra-eNodeB intra-frequency HO outgoing execution attempts in the source cell at point B. When the eNodeB receives an RRC Connection Reconfiguration Complete message from the UE, the eNodeB counts the number of successful intra-eNodeB intra-frequency outgoing HO executions in the source cell at point C. 
  Figure 1 Intra-eNodeB outgoing HO without RRC connection reestablishment
• Intra-eNodeB outgoing HO with RRC connection reestablishment
  Figure 2 illustrates an intra-eNodeB outgoing HO with RRC connection reestablishment, and the source and target cells operate at the same frequency. When the eNodeB sends an RRC Connection Reconfiguration message containing the handover command to the UE, the eNodeB counts the number of intra-eNodeB intra-frequency outgoing HO execution attempts in the source cell at point B. When the eNodeB receives an RRC Connection Reestablishment Complete message from the UE, the eNodeB counts the number of successful intra-eNodeB intra-frequency outgoing HO executions in the source cell at point C.

  Figure 2 Intra-eNodeB outgoing HO with RRC connection reestablishment

Inter-eNodeB Outgoing HO

Inter-eNodeB outgoing HOs can be further classified into HO without RRC connection reestablishment, HO with RRC connection reestablishment to the target cell, and HO with RRC connection reestablishment to the source cell.

• Inter-eNodeB outgoing HO without RRC connection reestablishment
  Figure 3 and Figure 4 illustrate X2- and S1-based outgoing HOs without RRC connection reestablishment, respectively, and the source cell and target cell operate on the same frequency. When the source eNodeB sends an RRC Connection Reconfiguration message containing the handover command to the UE, the source eNodeB counts the number of intra-frequency outgoing HO execution attempts in the source cell at point B. When the source eNodeB receives a UE Context Release message from the target eNodeB or receives a UE Context Release Command message from the MME, indicating that the UE successfully accesses the target cell, the source eNodeB counts the number of successful intra-frequency outgoing HO executions in the source cell at point C. 
   
• Inter-eNodeB outgoing HO with RRC connection reestablishment to the target cell
  Figure 5 and Figure 6 illustrate X2- and S1-based outgoing HOs with RRC connection reestablishment to the target cell, respectively, and the source cell and target cell operate on the same frequency. When the source eNodeB sends an RRC Connection Reconfiguration message containing the handover command to the UE, the source eNodeB counts the number of intra-frequency outgoing HO execution attempts in the source cell at point B. When the source eNodeB receives a UE Context Release message from the target eNodeB or receives a UE Context Release Command message from the MME, indicating that the UE successfully accesses the target cell, the source eNodeB counts the number of successful intra-frequency HO executions in the source cell at point C. 
   
• Inter-eNodeB outgoing HO with RRC connection reestablishment to the source cell
  Figure 7 and Figure 8 illustrate X2- and S1-based outgoing HOs with RRC connection reestablishment to the source cell, respectively, and the source cell and target cell operate on the same frequency. When the source eNodeB sends an RRC Connection Reconfiguration message containing the handover command to the UE, the source eNodeB counts the number of intra-frequency outgoing HO execution attempts in the source cell at point B. When the source eNodeB receives an RRC Connection Reestablishment Complete message from the UE, the source eNodeB counts the number of successful intra-frequency outgoing HO executions in the source cell at point C. 
   

Definition

The Intra-Frequency Handover Out Success Rate KPI is defined in Table 1. Note that the number of outgoing HO execution attempts and the number of successful outgoing HO executions are collected based on the description in Description.

Table 1 Intra-Frequency Handover Out Success Rate

Name	Intra-Frequency Handover Out Success Rate
Object	Cell or radio network
Formula	IntraFreqHOOut_SR = (IntraFreqHOOutSuccess/IntraFreqHOOutAttempt) x 100%
Associated Counters	Intra-Frequency Handover Out Success Rate = [(L.HHO.IntraeNB.IntraFreq.ExecSuccOut + L.HHO.IntereNB.IntraFreq.ExecSuccOut)/(L.HHO.IntraeNB.IntraFreq.ExecAttOut + L.HHO.IntereNB.IntraFreq.ExecAttOut)] x 100%
Unit	Percentage (%)
Note	None

Service Drop Rate (Always Online) -- LTE

Service Drop Rate (Always Online)

Description

The Service Drop Rate (Always Online) KPI indicates the call drop rate of all the services in a cell or radio network, including the VoIP services, when the always online state is active.
The Service Drop Rate (Always Online) KPI of all services is defined in Table 1.

Table 1 Service Drop Rate (Always Online)

Name	Service Drop Rate (Always Online)
Object	Cell or radio network
Formula	AlwaysOnline_CDR = (ERABAbnormalReleaseOfAlwaysOnline/ERABReleaseOfAlwaysOnline) x 100%
Associated Counters	Service Drop Rate (Always Online) =(L.E-RAB.AbnormRel/(L.E-RAB.AbnormRel + L.E-RAB.NormRel + L.E-RAB.Num.Syn2Unsyn)) x 100%
Unit/Range	Percentage (%)
Note	None

Service Drop Rate (All) -- LTE

Service Drop Rate (All)

Description

The Service Drop Rate (All) KPI indicates the call drop rate of all the services in a cell or radio network, including the VoIP service. Similar to the KPI defined in section 3.1 "Call Drop Rate (VoIP)", this KPI measures abnormal releases at the eNodeB.

Definition

The Service Drop Rate (All) KPI is defined in Table 1.

Table 1 Service Drop Rate (All)

Name	Service Drop Rate (All)
Object	Cell or radio network
Formula	Service_CDR = (ERABAbnormalRelease/ERABRelease) x 100%
Associated Counters	Service Drop Rate (All) =(L.E-RAB.AbnormRel/(L.E-RAB.AbnormRel + L.E-RAB.NormRel)) x 100%
Unit/Range	Percentage (%)
Note	None

Call Drop Rate (VoIP) -- LTE

Call Drop Rate (VoIP)

Description

The Call Drop Rate (VoIP) KPI indicates the call drop rate of the VoIP services in a cell or radio network. A VoIP call drop occurs when the VoIP E-RAB is abnormally released. Each E-RAB is associated with QoS information. Usually, the QCI of VoIP services is 1.
An E-RAB consists of a radio bearer and a corresponding S1 bearer. Any abnormal release of either bearer causes a call drop. A release is defined as abnormal by its release cause according to 3GPP TS 36.413.
Abnormal E-RAB releases can be classified into the following two scenarios, as shown in Figure 1.

 

Figure 1 Abnormal E-RAB release

• Scenario 1: When the eNodeB sends an E-RAB Release Indication message to the MME, the abnormal E-RAB release counter is incremented if the bearer to be released carries data and the release cause is not "Normal Release", "Detach", "User Inactivity", "CS Fallback triggered", "UE Not Available for PS Service", or "Inter-RAT Redirection".
• Scenario 2: When the eNodeB sends a UE Context Release Request message to the MME, the abnormal E-RAB release counter is incremented if the bearer to be released carries data and the release cause is not "Normal Release", "Detach", "User Inactivity", "CS fallback triggered", "UE Not Available For PS Service", "Inter-RAT redirection", "Time Critical Handover", "Handover Cancelled".

 NOTE:

• Except for the preceding two scenarios, the normal E-RAB release counter is incremented.
• If the message contains several E-RAB ID IEs (in the E-RAB To Be Released List IE), the counter will be incremented for each individual E-RAB.

Definition

The Call Drop Rate (VoIP) KPI is defined in Table 1.

Table 1 Call Drop Rate (VoIP)

Name	Call Drop Rate (VoIP)
Object	Cell or radio network
Formula	VoIP_CDR = (VoIPERABAbnormalRelease/VoIPERABRelease) x 100%
Associated Counters	Call Drop Rate (VoIP) = [L.E-RAB.AbnormRel.QCI.1/(L.E-RAB.AbnormRel.QCI.1 + L.E-RAB.NormRel.QCI.1)] x 100%
Unit/Range	Percentage (%)
Note	None

LTE Call Setup Success Rate

Call Setup Success Rate

Description

The Call Setup Success Rate KPI indicates the call setup success rate for all services, including the VoIP service in a cell or radio network. This KPI is calculated based on the RRC Setup Success Rate (Service) KPI, the S1 Signaling Connection Setup Success Rate KPI, and the E-RAB Setup Success Rate (All) KPI.

Definition

The Call Setup Success Rate KPI is defined in Table 1. The KPI is calculated by multiplying the RRC Setup Success Rate (Service) KPI, the S1 Signaling Connection Setup Success Rate KPI, and the E-RAB Setup Success Rate (All) KPI.

Table 1 Call Setup Success Rate

Name	Call Setup Success Rate
Object	Cell or radio network
Formula	CSSR = (RRCConnectionSuccessservice/RRCConnectionAttemptservice) x (S1SIGConnectionEstablishSuccess/S1SIGConnectionEstablishAttempt) x (ERABSetupSuccess/ERABSetupAttempt) x 100%
Associated Counters	Call Setup Success Rate =((L.RRC.ConnReq.Succ.Emc + L.RRC.ConnReq.Succ.HighPri + L.RRC.ConnReq.Succ.Mt + L.RRC.ConnReq.Succ.MoData + L.RRC.ConnReq.Succ.DelayTol)/(L.RRC.ConnReq.Att.Emc + L.RRC.ConnReq.Att.HighPri + L.RRC.ConnReq.Att.Mt + L.RRC.ConnReq.Att.MoData + L.RRC.ConnReq.Att.DelayTol)) x (L.S1Sig.ConnEst.Succ/L.S1Sig.ConnEst.Att) x (L.E-RAB.SuccEst/L.E-RAB.AttEst) x 100%
Unit/Range	Percentage (%)

E-RAB Setup Success Rate (All)

Description

The E-RAB Setup Success Rate (All) KPI indicates the E-RAB setup success rate for all services, including the VoIP service in a cell or radio network. This KPI is calculated based on the counters (both the E-RAB connection setup attempts [all] and the successful E-RAB setup [all] counters) measured at the eNodeB, as shown in Figure 1.

Definition

The E-RAB Setup Success Rate (All) KPI is defined in Table 1. The number of E-RAB connection setup attempts (all) and the number of successful E-RAB setup counters (all) are collected based on the description in Description.

Table 1 E-RAB Setup Success Rate (All)

Name	E-RAB Setup Success Rate (All)
Object	Cell or radio network
Formula	ERABS_SR = (ERABSetupSuccess/ERABSetupAttempt) x 100%
Associated Counters	E-RAB Setup Success Rate (All) =(L.E-RAB.SuccEst/L.E-RAB.AttEst) x 100%
Unit/Range	Percentage (%)
Note	None

E-RAB Setup Success Rate (VoIP)

Description

The E-RAB Setup Success Rate (VoIP) KPI indicates the E-RAB setup success rate of the voice over IP (VoIP) services in a cell or radio network.
According to 3GPP TS 36.300 and 3GPP TS 36.413, the counters related to this KPI are measured when the eNodeB receives an E-RAB Setup Request message or an Initial Context Setup Request message from the mobility management entity (MME), as shown in Figure 1 andFigure 2. The E-RAB is part of the Evolved Packet Service (EPS) bearer. According to 3GPP TS 23.401, an E-RAB is one or more Service Data Flows between UE and an EPC. The E-RAB identity remains unique for the UE even if the UE-associated logical S1-connection (S1 bearer) is released during periods of user inactivity. The E-RAB consists of both the E-RAB radio bearer (between the eNodeB and the UE, which is the same as the radio bearer defined in the EPS bearer) and the corresponding S1 bearer (between the eNodeB and the MME).

Figure 1 and Figure 2 show two scenarios: MME-initiated E-RAB setup (Scenario A) and UE-triggered E-RAB setup (Scenario B). Scenario B is triggered by the radio bearer setup. Initial Context Setup Request messages are exchanged between the eNodeB and the MME. If the E-RAB Setup Request message or Initial Context Setup Request message requires multiple E-RAB setups at the same time, specific counters are incremented for each E-RAB.

Definition

The E-RAB Setup Success Rate (VoIP) KPI is defined in Table 1. Note that the number of E-RAB connection setup attempts (VoIP) and the number of successful E-RAB setup connections (VoIP) are collected based on the descriptions in section Description.

Table 1 E-RAB Setup Success Rate (VoIP)

Name	E-RAB Setup Success Rate (VoIP)
Object	Cell or radio network
Formula	VoIPERABS_SR = (VoIPERABSetupSucces/VoIPERABSetupAttempt) x 100%
Associated Counters	E-RAB Setup Success Rate (VoIP) =(L.E-RAB.SuccEst.QCI.1/L.E-RAB.AttEst.QCI.1) x 100%
Unit/Range	Percentage (%)
Note	None

S1SIG Connection Setup Success Rate

Description

The S1SIG Connection Setup Success Rate KPI indicates the success rate of signaling connection setups over the S1 interface. This KPI includes counters such as the number of setup attempts of S1 signaling connections related to UEs and the number of successful setups of S1 signaling connections related to UEs.
The number of setup times of S1 signaling connections related to UEs is incremented by 1 each time when the eNodeB sends an INITIAL UE MESSAGE to the MME or receives the first message from the MME. INITIAL UE MESSAGE is the first S1 message that the eNodeB sends to the MME. It contains the NAS configuration information related to UEs, based on which the MME sets up S1 signaling connections for UEs. The first S1 message sent by the MME may be INITIAL CONTEXT SETUP REQUEST, DOWNLINK NAS TRANSPORT, or UE CONTEXT RELEASE COMMAND. Receiving any of these messages indicates that the S1 signaling connection is set up successfully.
As shown at point A in Figure 1, the L.S1Sig.ConnEst.Att counter is incremented by 1 when the eNodeB sends an INITIAL UE MESSAGE to the MME.
As shown at point B in Figure 1, the L.S1Sig.ConnEst.Succ counter is incremented by 1 when the eNodeB receives the first S1 message sent from an MME after sending an INITIAL UE MESSAGE to the MME.

Figure 1 signaling connection setup triggering point

Definition

The S1SIG Connection Setup Success Rate KPI is defined in Table 1. Note that the number of setup attempts of S1 signaling connections and the number of successful setups of S1 signaling connections are collected based on the description in Description.

Table 1 S1SIG Connection Setup Success Rate

Name	S1SIG Connection Setup Success Rate
Object	Cell/Radio Network
Formula	S1SIGS_SR = (S1SIGConnectionEstablishSuccess/S1SIGConnectionEstablishAttempt) x 100%
Associated Counters	S1SIG Connection Setup Success Rate =(L.S1Sig.ConnEst.Succ/L.S1Sig.ConnEst.Att) x 100%
Unit/Range	Percentage (%)

RRC Setup Success Rate (Signaling)

Description

The RRC Setup Success Rate (Signaling) KPI indicates the RRC setup success rate of the signaling-related cause (mo-signaling) in a cell or radio network.
Like the RRC Setup Success Rate (service), the RRC Setup Success Rate (Signaling) KPI is used to calculate the RRC setup success rate only when the "establishmentCause" field is set to mo-signaling in a cell or radio network.

Definition

The RRC Setup Success Rate (Signaling) KPI is defined in Table 1. Note that the number of RRC connection setup attempts (signaling) and the number of successful RRC setup connections (signaling) are collected based on the description in Description.

Table 1 RRC Setup Success Rate (Signaling)

Name	RRC Setup Success Rate (Signaling)
Object	Cell or radio network
Formula	RRCS_SRsignaling = (RRCConnectionSuccesssignaling/RRCConnectionAttemptsignaling) x 100%
Associated Counters	RRC Setup Success Rate (Signaling) =(L.RRC.ConnReq.Succ.MoSig/L.RRC.ConnReq.Att.MoSig) x 100%
Unit/Range	Percentage (%)
Note	None

RRC Setup Success Rate (Service)

Description

According to 3GPP TS 36.331, the RRC connection setup procedure is triggered by different causes, which are identified in the "establishmentCause" field in an RRC Connection Request message as emergency, highPriorityAccess, mt-Access, mo-Signaling, mo-Data, or delayTolerantAccess-v1020. The UE sets the establishmentCause in accordance with the information it receives from upper layers. The mo-signaling cause is a signaling-related cause. All other causes are service-related causes. The accessibility KPI evaluates the RRC setup success rate using service-related causes in a cell or radio network.
The RRC Setup Success Rate (Service) KPI is calculated based on the counters measured at the eNodeB when the eNodeB receives an RRC Connection Request message from the UE, as shown in Figure 1. The number of RRC connection attempts is collected by the eNodeB at measurement point A, and the number of successful RRC connections is counted at measurement point C.

Figure 1 Measurement points for RRC connection setup

Definition

The RRC Setup Success Rate (Service) KPI is defined in Table 1. Note that the number of RRC connection setup attempts (service) and the number of successful RRC setup connections (service) are collected based on the description in Description.

Table 1 RRC Setup Success Rate (Service)

Name	RRC Setup Success Rate (Service)
Object	Cell or radio network
Formula	RRCS_SRservice = (RRCConnectionSuccessservice/RRCConnectionAttemptservice) x 100%
Associated Counters	RRC Setup Success Rate (Service) =((L.RRC.ConnReq.Succ.Emc + L.RRC.ConnReq.Succ.HighPri + L.RRC.ConnReq.Succ.Mt + L.RRC.ConnReq.Succ.MoData + L.RRC.ConnReq.Succ.DelayTol)/(L.RRC.ConnReq.Att.Emc + L.RRC.ConnReq.Att.HighPri + L.RRC.ConnReq.Att.Mt + L.RRC.ConnReq.Att.MoData + L.RRC.ConnReq.Att.DelayTol)) x 100%
Unit/Range	Percentage (%)
Note	None