QCI.9 vs CQI

[mounir34]

dears

please need support to explain to us why the CQI degraded after The QCI 9 traffic increase in our Network
caused throughput degraded as shown on below picture i want to know:

1- what's the different between QCI6 and QCI9 ?
2-if the QCI 9 more sensitive the RF Condition thenb QCI 6 ?
3- what' s the relation between QCI and CQI ?

PS// The QCI 6 no change

your support is highly recommended ,thx for everyone

40987

[samuraial]

This case looks more like a MME side case than a radio one.
Ask your MME guys to check the QCI configuration in their side if they made any mistake and they should do it according to 3gpp standards.
LTE QCI-1 to QCI-9

LTE QCI Resource Type Priority Packet Delay Budget Packet Error Loss Rate Example Services
QCI-1 GBR 2 100ms 10-2 Conversational voice
QCI-2 4 150ms 10-3 live streaming of conversational voice
QCI-3 3 50ms Real time gaming
QCI-4 5 300ms 10-6 Non conversational video(Buffered streaming)
QCI-5 Non-GBR 1 100ms IMS signalling
QCI-6 6 300ms Video (buffered streaming),TCP based applications
QCI-7 7 100ms 10-3 Voice, video (live streaming) , interactive gaming
QCI-8 8 300ms 10-6 Video (Buffered streaming) , TCP based applications
QCI-9 9


B/R

[mounir34]

yes already checked the configuration is OK


This case looks more like a MME side case than a radio one.
Ask your MME guys to check the QCI configuration in their side if they made any mistake and they should do it according to 3gpp standards.
LTE QCI-1 to QCI-9

LTE QCI Resource Type  Priority  Packet Delay Budget  Packet Error Loss Rate Example Services
QCI-1 GBR 2 100ms 10-2 Conversational voice
QCI-2 4 150ms 10-3 live streaming of conversational voice
QCI-3 3 50ms Real time gaming
QCI-4 5 300ms 10-6 Non conversational video(Buffered streaming)
QCI-5 Non-GBR 1 100ms IMS signalling
QCI-6 6 300ms Video (buffered streaming),TCP based applications
QCI-7 7 100ms 10-3 Voice, video (live streaming) , interactive gaming
QCI-8 8 300ms 10-6 Video (Buffered streaming) , TCP based applications
QCI-9 9


B/R

[samuraial]

Now that I look it closely to the graphs the degradation started before the QCI9 traffic increased around 9 and in your case if not wrong the QCI9 traffic could be due to start of the month packages being refilled.(we have max package 28days in our country)
One general idea could be due to increase in load and interference the report a bad CQI so check the MCS values also if they are the same.
Use the capacity rank2 formula to see if there is any degradation in QOS, the lower the worst is the general idea.
Capacity RANK2 = [L.ChMeas.RI.Rank2]/([L.ChMeas.RI.Rank1]+[L.ChMeas.RI.Rank2])*{100}

Interference counters also would be good to check.

B/R

[mounir34]

dear
please check below ,
the CQI Degraded and the MCS keep the same trend is it normal !!!!!!

MCS VS RANK2 Capacity

40989

CQI vs RANK2 Capacity

40990

Interference
40991




Now that I look it closely to the graphs the degradation started before the QCI9 traffic increased around 9 and in your case if not wrong the QCI9 traffic could be due to start of the month packages being refilled.(we have max package 28days in our country)
One general idea could be due to increase in load and interference the report a bad CQI so check the MCS values also if they are the same.
Use the capacity rank2 formula to see if there is any degradation in QOS, the lower the worst is the general idea.
Capacity RANK2 = [L.ChMeas.RI.Rank2]/([L.ChMeas.RI.Rank1]+[L.ChMeas.RI.Rank2])*{100}

Interference counters also would be good to check.

B/R

[samuraial]

I am on my phone now and tomorrow I can check better but you seem to have radio condition degradation there. What changes were made at date 9 where the rank2 drops like that?
If you check better the MCS improved/interfernce improved CQI degraded.
Did you change anything regarding scheduling of edge users?
Lst optlog in the eNodeB and watch changes from 8 till 25.

B/R

[mounir34]

dears
any support ,
note also that we enable ArpPrioritySchSwitch



I am on my phone now and tomorrow I can check better but you seem to have radio condition degradation there. What changes were made at date 9 where the rank2 drops like that?
If you check better the MCS improved/interfernce improved CQI degraded.
Did you change anything regarding scheduling of edge users?
Lst optlog in the eNodeB and watch changes from 8 till 25.

B/R

[samuraial]

I have read the description for the switch, can you roll it back?

B/R

[mounir34]

yes can but i want to know if the degradation caused by this feature ,from my point of you its not related but i want to confirm
what do you think,


I have read the description for the switch, can you roll it back?

B/R

[samuraial]

Well if the feature was opened during the time you had the degradation that is for sure the cause. As I remember as I am home now when the switch was ON it disabled some other mechanism that was active when it was OFF.(from switch explanation in U2000)
Your graphs shows a degradation like a knife cut so if the change was during this time could be the cause.
You could also check the CHR to see if there is any problem with any type of UE.
Tomorrow I will check this feature again.
When was the exact time you have open this switch?

B/R

[mounir34]

we already close this feature in some eNodeB's to confirm i will share with you the result ,


Well if the feature was opened during the time you had the degradation that is for sure the cause. As I remember as I am home now when the switch was ON it disabled some other mechanism that was active when it was OFF.(from switch explanation in U2000)
Your graphs shows a degradation like a knife cut so if the change was during this time could be the cause.
You could also check the CHR to see if there is any problem with any type of UE.
Tomorrow I will check this feature again.
When was the exact time you have open this switch?

B/R

[samuraial]

Please close it to the eNB that had big change in the KPI. So we can see it better.

B/R

[mounir34]

we switched on the ARP Switch and no change ,please any suggestion

40993



Please close it to the eNB that had big change in the KPI. So we can see it better.

B/R

[samuraial]

You have switched it off or have you switched it ON? When you show a graph please put the time you have made the changes and also the time you did a rollback. In the network sudden degradation like the one you showed cannot happen without a change, be it rf/core side. Please post the graph with 2 lines showing the time of the first change and the rollback time.
Also try to see if there is some sites having the problem or all had the same problem.
From your graph i can see the KPIs are increasing in the last part.

B/R

[mounir34]

we switched of the ARP feature but no chnage in KPI means the degradation not related to this feature ,


You have switched it off or have you switched it ON? When you show a graph please put the time you have made the changes and also the time you did a rollback. In the network sudden degradation like the one you showed cannot happen without a change, be it rf/core side. Please post the graph with 2 lines showing the time of the first change and the rollback time.
Also try to see if there is some sites having the problem or all had the same problem.
From your graph i can see the KPIs are increasing in the last part.

B/R

[marcengo]

Correct me if I`m wrong, but, you increased the traffic from ~200Gbit to ~800Gbit with a variation of ~0.1 in CQI?

If yes, there is nothing wrong with you network. Increase in traffic will lead to increase in CQI. Since the range is ~0.1 you may not see similar behavior in MCS.

To be extra careful, try to get counters which show HARQ ReTx to see if there is any abnormality. Remember that 10% is the target for PS services.

[samuraial]

His drop was like 0.5 in the CQI but if you see the last graph there is a recovery in the CQI KPIs.
Please update us how did it go?

B/R