Measurement Counter
A9101:DOWN_GPRS_TBF_ESTB_ATMP
Description
This measurement provides the number of downlink GPRS TBF establishment attempts in a granularity period. Together with Number of Failed Downlink GPRS TBF Establishments due to No Channel and Number of Downlink GPRS TBF Abnormal Releases due to No Channel, this measurement indicates the congestion of the downlink GPRS TBF due to no channel in a granularity period. Together with Number of Successful Downlink GPRS TBF Establishments, this measurement indicates the downlink assignment success rate in a granularity period. Together with other measurements, this measurement indicates the PDCH packet assignment success rate in a granularity period.
Unit
Integer number or integer.
Measurement Point
Downlink GPRS TBF establishment attempts due to no channel resource, no response from the MS, or other causes.
In a granularity period, after the BSC receives a new downlink PDU request from the SGSN, the downlink GPRS TBF establishment fails due to no channel resource, no response from the MS, or other causes, the counter is incremented by one.
Downlink GPRS TBF establishment attempts on the CCCH
The BSC attempts to establish downlink GPRS TBF by sending the IMMEDIATE ASSIGNMENT message at the subtimeslots corresponding to the CCCH group where the MS belongs. Figure 1 shows the procedure in which the BSC sends an IMMEDIATE ASSIGNMENT message on the CCCH. Each time the BSC sends an IMMEDIATE ASSIGNMENT message (see measurement point A), the counter is incremented by one.
Figure 1 Downlink packet immediate assignment
Downlink GPRS TBF establishment attempts on the PACCH
The BSC attempts to establish the downlink GPRS TBF by sending a PACKET DOWNLINK ASSIGNMENT message to the MS during the transmission process of the previous uplink GPRS TBF or the release process of the current downlink GPRS TBF. Figure 2 shows the procedure in which the BSC sends the PACKET DOWNLINK ASSIGNMENT message. Each time the BSC sends a PACKET DOWNLINK ASSIGNMENT message (see measurement point A), the counter is incremented by one.
Figure 2 Downlink assignment on the PACCH
Formula
This is an original counter without involving any formula.