Number of Downlink GPRS TBF Abnormal Releases due to N3105 Overflow

Measurement Counter

A9106:DOWN_GPRS_TBF_ABNORM_REL_N3105_OVERFLOW

Description

This measurement provides the number of downlink GPRS TBF abnormal releases due to N3105 overflow in a granularity period. A high measurement value is yielded because the radio quality of the cell is bad.

Unit

Integer number or integer.

Measurement Point

During the downlink GPRS TBF transmission, the BSC periodically sends the block with the RRBP flag to reserve the blocks for the MS to respond with the PACKET DOWNLINK ACK/NACK message. The purpose is to check the downlink receiving conditions. If the BSC receives the PACKET DOWNLINK ACK/NACK message in the radio block assigned to the MS within a certain period predefined by the BSC timer, the N3105 is reset. Otherwise, the N3105 is incremented by one and the BSC resends the block with RRBP flag. If the N3105 overflows, the BSC initiate the downlink GPRS TBF release procedure. Figure 1 shows the procedure of downlink GPRS TBF abnormal release due to no response from the MS. Each time the N3105 overflows (see measurement point A), the counter is incremented by one.

Figure 1 Abnormal release of the downlink GPRS TBF due to N3105 overflow

Formula

This is an original counter without involving any formula.