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chronix_ray
2014-04-01, 01:07 PM
Hi,

We are using NSN equipment. Im checking worst cell with hight SDCCH drops and found that some of the sites are having high IMSI detach more than 2500 attempts per day and that cause my LU to increase hence my SDCCH drop due to radio failure increases. What can I do/check to reduce IMSI detach or what causes this?

BR//

electron
2014-04-01, 02:26 PM
Hi,

Are the worst cells located in one LAC? I guess problem is from core side not radio side. For example if due to increasing intensity of paging your DRX cycle increase then UE battry consumption will increase and UEs morre than usual will be off then IMSI detach will increase in the network.


Cheers
Hi,

We are using NSN equipment. Im checking worst cell with hight SDCCH drops and found that some of the sites are having high IMSI detach more than 2500 attempts per day and that cause my LU to increase hence my SDCCH drop due to radio failure increases. What can I do/check to reduce IMSI detach or what causes this?

BR//

chronix_ray
2014-04-01, 02:47 PM
Hi,

Cells are in the same LAC. I think the number of IMSI detach attempts are not the usual because it is much gretaer than the number of SDCCH seizures.

BR//

khurrambilal01
2014-04-01, 03:58 PM
Hi,

Cells are in the same LAC. I think the number of IMSI detach attempts are not the usual because it is much gretaer than the number of SDCCH seizures.

BR//


Is this a global issue or some specific cells only? If it is related to some cells it might be because of coverage and if it's Global then you have t audit Core Detach parameters.

chronix_ray
2014-04-01, 05:07 PM
Hi,

this is only for some cells. So this is a core side issue?

Br//

khurrambilal01
2014-04-01, 06:50 PM
If its related to some specific cells that i suspect it might be due to some specific MS which don't follow 3GPP specifications (Normally Chinese handsets), You have to trace these cells and see either these IMSI detach are from specific MS or all of users in those cells.

I have observed wired behaviour from some MS earlier using trace.

Additionally learn to say thanks, this forum is build to support each other and morally we need to say thanks if someone helps us!

plannerguy
2014-04-10, 11:45 PM
Hi

Kindly chekc the Timer 3212 at Core side and on BSS side.

Rgds
Plannerguy