Call Drops due to Equipment Failure (Signaling Channel)

Measurement Counter

CM364:CELL_SIG_CALL_DROPS_EQUIP_FAIL

Description

After the MS seizes a channel, if the status of the BSC internal resources is abnormal, the BSC releases the call that seizes the abnormal resources.

This measurement provides the number of call releases by the BSC on the signaling channel due to the abnormal state of internal resources.

Unit

Integer number or integer.

Measurement Point

When an SDCCH or a TCH is seized to carry signaling during a call, this counter is measured in the following situations:

A call drop occurs because of any of the following: TRX mutual aid; dynamic modification of cell attributes, TRX frequencies, or TRX FH data; dynamic deletion of cells or TRXs; blocking of cells, TRXs, or channels.
The timer set to wait for the outgoing BSC handover command expires, or the clear request message is received from the MSC before the timer expires, and the handover cause is other causes than OM intervention, MSC triggering, or preemption.
A call drop occurs because of call assignment failure during the handover.
The MSC cannot send a short message because of the restriction on sending downlink short messages in data configuration or because of flow control, and then the call is released.
A call drop occurs because of software error.

This counter is calculated at A4, as shown in Figure 1, Figure 2, Figure 3, Figure 4, and Figure 5.

Figure 1 Call drops in the immediate assignment (including very early assignment) procedure

A1: Call Drops Due to ERR IND Received in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Overlaid Subcell in Stable State

A2: Call Drops Due to the CONN FAIL IND Received in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Overlaid Subcell in Stable State

A3: Call Drops Due to REL IND Received in Stable State, Call Drops Due to the REL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the REL IND Received on the TRX in the Overlaid Subcell in Stable State

A4: Call Drops Due to No MRs from MS for a Long Time, Call Drops Due to No MR from the MS on the TRX in the Underlaid Subcell, Call Drops Due to No MR from the MS on the TRX in the Overlaid Subcell, Call Drops due to Abis Terrestrial Link Failure, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Underlaid Subcell, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Overlaid Subcell, Call Drops Due to Equipment Failure, Call Drops Due to TRX Failure in the Underlaid Subcell, Call Drops Due to TRX Failure in the Overlaid Subcell, Call Drops due to Resource Check, Call Drops Due to Resource Check on the TRX in the Underlaid Subcell, Call Drops Due to Resource Check on the TRX in the Overlaid Subcell

A5: Clear Requests Sent on the A Interface

A6: Call Drops Due to Forced Handover, Call Drops Due to Forced Handover on the TRX in the Underlaid Subcell, Call Drops Due to Forced Handover on the TRX in the Overlaid Subcell

A10: Successful SDCCH Seizures (Call Type)

Figure 2 Call drops in the assignment and intra-cell handover (TCH handover) procedure

A1: Call Drops Due to ERR IND Received in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Overlaid Subcell in Stable State

A2: Call Drops Due to the CONN FAIL IND Received in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Overlaid Subcell in Stable State

A3: Call Drops Due to REL IND Received in Stable State, Call Drops Due to the REL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the REL IND Received on the TRX in the Overlaid Subcell in Stable State

A4: Call Drops Due to No MRs from MS for a Long Time, Call Drops Due to No MR from the MS on the TRX in the Underlaid Subcell, Call Drops Due to No MR from the MS on the TRX in the Overlaid Subcell, Call Drops due to Abis Terrestrial Link Failure, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Underlaid Subcell, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Overlaid Subcell, Call Drops Due to Abis Link Failures in Stable Loopback State, Call Drops Due to Equipment Failure, Call Drops Due to TRX Failure in the Underlaid Subcell, Call Drops Due to TRX Failure in the Overlaid Subcell, Call Drops Due to Resource Check, Call Drops Due to Resource Check on the TRX in the Underlaid Subcell, Call Drops Due to Resource Check on the TRX in the Overlaid Subcell, Call Drops Due to Handover Failure During the Loopback, Call Drops Due to Other Causes in Stable State

A5: Clear Requests Sent on the A Interface, Call Drops after Answer, Call Drops After Answer on the TRX in the Underlaid Subcell, Call Drops After Answer on the TRX in the Overlaid Subcell

A6: Call Drops Due to Forced Handover, Call Drops Due to Forced Handover on the TRX in the Underlaid Subcell, Call Drops Due to Forced Handover on the TRX in the Overlaid Subcell, Failed Internal Intra-Cell Handovers (Timer Expired)

A7: Call Drops Due to Loopback Start Failure

A8: Successful TCH Seizures on the TRX in the Underlaid Subcell, Successful TCH Seizures on the TRX in the Overlaid Subcell, Call Drops Due to Failures to Return to Normal Call from Loopback

A9: Successful Connections

Figure 3 Call drops in the intra-BSC handover procedure (including the signaling channel and TCH)

A1: Call Drops Due to ERR IND Received in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Overlaid Subcell in Stable State

A2: Call Drops Due to the CONN FAIL IND Received in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Overlaid Subcell in Stable State

A3: Call Drops Due to REL IND Received in Stable State, Call Drops Due to the REL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the REL IND Received on the TRX in the Overlaid Subcell in Stable State

A4: Call Drops Due to No MRs from MS for a Long Time, Call Drops Due to No MR from the MS on the TRX in the Underlaid Subcell, Call Drops Due to No MR from the MS on the TRX in the Overlaid Subcell, Call Drops due to Abis Terrestrial Link Failure, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Underlaid Subcell, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Overlaid Subcell, Call Drops Due to Abis Link Failures in Stable Loopback State, Call Drops Due to Equipment Failure, Call Drops Due to TRX Failure in the Underlaid Subcell, Call Drops Due to TRX Failure in the Overlaid Subcell, Call Drops Due to Resource Check, Call Drops Due to Resource Check on the TRX in the Underlaid Subcell, Call Drops Due to Resource Check on the TRX in the Overlaid Subcell, Call Drops Due to Other Causes in Stable State

A5: Clear Requests Sent on the A Interface, Call Drops after Answer, Call Drops After Answer on the TRX in the Underlaid Subcell, Call Drops After Answer on the TRX in the Overlaid Subcell

A6: Call Drops Due to Forced Handover, Call Drops Due to Forced Handover on the TRX in the Underlaid Subcell, Call Drops Due to Forced Handover on the TRX in the Overlaid Subcell, Failed Internal Intra-Cell Handovers (Timer Expired), Failed Outgoing Internal Inter-Cell Handovers (Timer Expired), Call Drops Due to Handover Failure During the Loopback

A7: Call Drops due to Failures to Return to Normal Call from Loopback

A8: Successful TCH Seizures on the TRX in the Underlaid Subcell, Successful TCH Seizures on the TRX in the OverLaid Subcell

A9: Successful Connections

A10: Successful SDCCH Seizures (Call Type)

Figure 4 Call drops in the outgoing BSC handover procedure (including the signaling channel and traffic channel)

A1: Call Drops Due to ERR IND Received in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Overlaid Subcell in Stable State

A2: Call Drops Due to the CONN FAIL IND Received in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Overlaid Subcell in Stable State

A3: Call Drops Due to REL IND Received in Stable State, Call Drops Due to the REL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the REL IND Received on the TRX in the Overlaid Subcell in Stable State

A4: Call Drops Due to No MRs from MS for a Long Time, Call Drops Due to No MR from the MS on the TRX in the Underlaid Subcell, Call Drops Due to No MR from the MS on the TRX in the Overlaid Subcell, Call Drops due to Abis Terrestrial Link Failure, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Underlaid Subcell, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Overlaid Subcell, Call Drops Due to Abis Link Failures in Stable Loopback State, Call Drops Due to Equipment Failure, Call Drops Due to TRX Failure in the Underlaid Subcell, Call Drops Due to TRX Failure in the Overlaid Subcell, Call Drops Due to Resource Check, Call Drops Due to Resource Check on the TRX in the Underlaid Subcell, Call Drops Due to Resource Check on the TRX in the Overlaid Subcell, Call Drops Due to Other Causes in Stable State

A5: Clear Requests Sent on the A Interface

A6: Call Drops Due to Forced Handover, Call Drops Due to Forced Handover on the TRX in the Underlaid Subcell, Call Drops Due to Forced Handover on the TRX in the Overlaid Subcell, Failed Outgoing External Inter-Cell Handovers (T8 Expired), Call Drops Due to Handover Failure During the Loopback

A9: Successful Connections

Figure 5 Call drops in the incoming BSC handover procedure (including the signaling channel and traffic channel)

A1: Call Drops Due to ERR IND Received in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Overlaid Subcell in Stable State

A2: Call Drops Due to the CONN FAIL IND Received in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Overlaid Subcell in Stable State

A3: Call Drops Due to REL IND Received in Stable State, Call Drops Due to the REL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the REL IND Received on the TRX in the Overlaid Subcell in Stable State

A4: Call Drops Due to No MRs from MS for a Long Time, Call Drops Due to No MR from the MS on the TRX in the Underlaid Subcell, Call Drops Due to No MR from the MS on the TRX in the Overlaid Subcell, Call Drops due to Abis Terrestrial Link Failure, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Underlaid Subcell, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Overlaid Subcell, Call Drops Due to Abis Link Failures in Stable Loopback State, Call Drops Due to Equipment Failure, Call Drops Due to TRX Failure in the Underlaid Subcell, Call Drops Due to TRX Failure in the Overlaid Subcell, Call Drops Due to Resource Check, Call Drops Due to Resource Check on the TRX in the Underlaid Subcell, Call Drops Due to Resource Check on the TRX in the Overlaid Subcell, Call Drops Due to Other Causes in Stable State

A5: Clear Requests Sent on the A Interface

A6: Call Drops Due to Forced Handover, Call Drops Due to Forced Handover on the TRX in the Underlaid Subcell, Call Drops Due to Forced Handover on the TRX in the Overlaid Subcell, Failed Incoming External Inter-Cell Handovers (Timer Expired), Call Drops Due to Handover Failure During the Loopback

A7: Call Drops due to Failures to Return to Normal Call from Loopback

A8: Successful TCH Seizures on the TRX in the Underlaid Subcell, Successful TCH Seizures on the TRX in the OverLaid Subcell

A9: Successful Connections

A10: Successful SDCCH Seizures (Call Type)

Formula

Call Drops due to Equipment Failure (Signaling Channel) = [Call Drops Due to Equipment Failure (SDCCH)] + [Call Drops due to Equipment Failure (TCHF) (Signaling Channel)] + [Call Drops due to Equipment Failure (TCHH) (Signaling Channel)]