Zte ZXG10 OB06, Technical Manual

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Chapter 4 - System Functions
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2. General overload
The OB06 instructs the BSC that the receiver must reduce the traffic.
According to the protocol, it can be used to indicate the TRX overload,
downlink CCCH overload and ACCH overload.
The TRX processor provides data from the bottom running operating
system. The downlink CCCH load calculation is just the same as the
above-mentioned CCCH LOAD IND, the CHP provides the RACH load,
and the PAGCHM provides the PCH load. The ACCH load calculation is
not determined.
According to the negotiation with the BSC, the current general
overload (OVER LOAD) is only used to report the RACH load that is
provided by the CHP.
Error Indication
The procedure of error indication is shown in Figure 58.
F
I G U R E
5 8 E
R R O R
I
N D I C A T I O N
MS LAPDm FURRM HPIMan LAPD
BSC OAMM
Dm _ M DL_ ERR
OR_IND
DL _DATA _REQ (ERROR IND)
(ERROR IND)
The ERROR IND message that is sent from the OB06 to the BSC indicates
to the BSC that the following abnormities happen in the radio data link
layer.
The ERROR IND message contains the related error cause information,
including the following causes:
1. Protocol errors, as listed in Sections 5.6.4, 5.7.3 and Appendix G in TS
GSM 04.06;
2. Error with one link layer. In other words, the I frame is repeated for
N200 times but is not acknowledged.
3. The SABM or DISC frame is repeated for N200 times but is not
acknowledged.
4. The SABM frame received in the multiframe establishment status