CORE NETWORK PARAMETER THAT CAUSES SDCCH DROPS

[expert maxwell]

Hello experts,
can anyone help me with core network parameters that can affect SD drops along country borders. a core network parameter was changed and its causing all cells on the country border to drop massively on SD.
i have checked and optimise all BSIC and have also ruled out interfernce.
please help me out.

thanks.

[striker]

Check the ciphering for MSC and BSC ciphering they should be the same....

[expert maxwell]

thank you. am checking

[expert maxwell]

i checked the ciphering algorithm and they are the same. A5/1

[arjaypanganiban]

What specific parameter in Core was changed? Do you have any idea?

[expert maxwell]

no, the core guys does not really have an idea. that is what am also try to found out.
i am looking for core parameters that can affect sdcch drops.

[Nasrin]

i am not core expert,but it should be related to Roaming parameters and protocols,

[consultant]

Check once more time NCC and BCC, send also drive test team with Tems for further analisys.
I think it is related to the change of frequency plan in the roaming network.

[lamagica]

imo you should check by the counter, where the sdcch drop occurred.. is it in rf, abis or aif.
if there were some problem in core network, the sdcch drop in aif should be the majority contributor

[luganomu]

SD drop is categorised into four groups which are:-
1.Sdcch_drop_ss
2.Sdcch_drop_Qual
3.Sdcch_drop_TA
4.Sdcch_drop_other
So you need to check those boarder cells and identify which counter contain many counts from the four categories above then from there we can know where to start.