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BENRHOUMASALEM
2012-07-05, 06:59 AM
Hi all,
i have question if someone can help me.
in KPI of congestion SDCCH Rate, we count repetation ?

BR

stream19
2012-07-07, 01:53 AM
what you meam by counting repetition?

BENRHOUMASALEM
2012-07-07, 06:24 AM
when i request for SDCCH but there is no SDCCH ressources.
So after timer, the mobile will repet the request for Nbre retransmission + 1
so the KPI of congestion will be so high

stream19
2012-07-11, 04:50 AM
logical cases so I think you have to increase the number of SDCCH capacity of this cell ....

peanut
2012-07-11, 05:19 AM
Dear,

First blocking is not congestion

blocking is the situation when there is no ressources and a new user request a ressource then fail
congestion is the situation when there is no ressources

I mean we can have congestion without blocking, and this is not a problem

now you are asking about sdcch blocking, when the same user retry a service request to cell, should we count this second retry or not when calculating the sdcch blocking?

I checked a formula for sdcch blocking used in ********, and they count all failures here is the formula:

sdcch_blocking_rate = (sdcch_alloc_fail) / (sdcch_alloc_fail+ sddch_alloc)

perhaps there is no mean to distinguish users based on service request message as this the first steps to connect to cell and there is no authentication of user yet.

but I agree with you that this will lead to biased numbers, so try to correlate this number with congestion time.

regards,

a little click on http://www.finetopix.com/images/buttons/ha_thumbsup.gif is very appreciated

binladen
2012-07-11, 05:13 PM
The first you check card have failure or not. Can add more timeslot SDCCH, check neighbor around

melkaiy
2012-07-12, 11:12 PM
check the configuration my friend. u can see if there are congestion first by looking the location area update then check the sdcch configuration in every sector

RF Engr
2012-07-19, 08:19 PM
1st Check SDCCH Traffic.
2nd Available Timeslots in that Hour
3rd Alarm on site
4th Check number of SD attempts in that hour
5th Check location update request are happening in that cell or not
After analyzing all this then u can decide to add SD TS.

ferrocious
2012-07-20, 08:50 PM
In SDCCH Blocking, immediate assignment is sent once, if congested it will fail, and not send again, no new transmission is done. In case of no response after immediate assignment it will re-transmit but its counted as one in some vendors and multiple times in others. depends upon the counter and formula definition.

Ans to your question is "no" in congestion it will not :)

melkaiy
2012-07-21, 11:01 PM
you should check the sddch dynamic allocation if it is active or not.. blocking is possible due to sdcch congestion you can also check the configuration in every cell, it's quite hard and tiring but you have to check it per affected site or cluster. check also the channel elements in the card and tally it with the erlang b table.

if this one helps please add reps :)