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Hello all,
I’m bit confused on paging response.
Can I assume that if cell A has high ‘SDCCH assign fail’ leads to low paging success in NSS ?Yes.Of course if the cell is having very high traffic as compared to other cells in that LAC.
You can improve by enabling paging response on FACCHThanks Bijoy,
Cell A has high, around 14% SDCCH assign fail due to radio and the LAC has low paging response success.
My main question is:
Is paging response sent to NSS after successful SDCCH assignment?hI BIJOY,
BUT IN THAT CASE IN CELL IDLE TCH MUST BE THERE OTHERWISE TCH CONGESTION WILL OCCUR.
The paging response is sent to the NSS when the MS gets its SDCCH.
So yes, poor sdcch failure rate leads to poor paging success rate : the MS doesn’t get its SDCCH to send the answer.
>> Bijoy : what is the correlation with LAC ?
>> Krish : TCH congestion is not counted as paging failure. The paging is successful but the call setup is failed.
Thanks All,
I have my answer clear.
Pix
Most operators use LAC wise paging strategy(I think the n/w of Amo also uses the same strategy),so if in that LAC a particular cell has exceptionally high traffic with SDCCH blocking,paging response for that LAC will be poor.Bijoy,
Ok, I understand , thanks 🙂
Hi pix,
i am talking abt fach call set up not paging so if u are enabling fach call set up then u must have idle tch otherwise tch congestion will occur
Krish,
We don’t have the FACCH call setup in ALU, so I don’t really know how it works. It seems much better than SDCCH + TCH call setup.
And yes, you might be right, in case of TCH congestion + FACCH Call Setup, that would also lead to paging failure… but isn’t there some kind of fallback onto SDCCH if the TCH is congesteed ? As a backup plan ?
Cheers,
pixHi pix,
fach call set up u can use where sd blocking .in this assignment will be first on tch and only after that if no tch will be available then it will use sdcch.
Krish,
So even in case of TCH congestion, the paging could be answered with a proper SDCCH. Therefore it is the SDCCH congestion that directly relates to the Paging Failure. What do you think ?
Krish & Pix,
BSC will never use FACCH call set up if sdcch is available. If there is no SDCCH available BSC tries to allocate FACCH for call set up signalling instead of rejecting the call.
So both SDCCH + TCH congestion will cause paging failure.
Also I think FACCH call set up is optional feature in BSC so mostly SDCCH congestion shall cause pg failure.
Hi silence,
no its not right.u can define on cell level that ur first immediate assignment will be on tch or sdcch . in eric there is chap parameter thr which ucan define.
I agree with kish..in ericsn network by Channel Allocation Profile (CHAP)feature u can set the immediate assignment whether at sdcch or tch priority..but as recommended this feature must only be utilise only at cells with high SDCCH congestion
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