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safoot
2011-12-13, 12:23 AM
Hi Gents,
I have a problem in HSDPA throughput for 2E1s sites having the throughput limited to 2.75Mbps maximum while as for other vendors it reaches 3.3Mbps! We have checked all possible resources limitations but reached a conclusion that there's no limitation from the Radio, Buffer or Scheduler parts.
Can the problem be in the ATM switch used? Also what is the optimum PCR and CDVT values for HSDPA to be assigned from Radio part.

Please share your insights as the problem is very critical.

Thanks,

satria
2011-12-13, 12:40 AM
Are u using dual IUB or Pure ATM?

safoot
2011-12-13, 12:46 AM
No We're using here pure ATM and mainly the sites having 2E1s suffer from this problem

satria
2011-12-13, 12:55 AM
Assume that all radio condition having no issue,CE enough,power is ok and all related radio parameters are ok .

You can check the Transmission Setting:
-How Many VCC for your IUB?

-Check the CID Utilization using this counter for HSDPA VC?
CID Util % = (M550C6/248) * 100
CID Util % = MAX_AAL2_CONNECTIONS/248 * 100

-You can optimize by separating between VC per USAGE
AAL2UPUsage:
DCH
HSDPA
DCH & HSDPA

AAL2PathType:
Stringent & Stringent bi-level
Stringent & Stringent bi-level
Stringent & Stringent bi-level & Tolerant
Tolerant

If this help full,please THANKS & REPUTATION.

safoot
2011-12-14, 05:24 PM
Hi Satria,
Thanks a lot for your valuable reply, however as I stated it's not a problem in congestion of problem of VCC blocking due to max. number of connections as it is happening on the whole network, there's no single site having 2E1 on which we can have a throughput higher than 2.75Mbps while for Huawei they can reach 3.2Mbps! I guess the problem may be because in Huawei they don't have the same IUb dimensioning in NSN that divides it into VCCs some of them are dedicated and some are shared, however they use a different algorithm that may take into account all unused resources to be used whenever needed.
Please correct me if I'm wrong and I'd appreciate if someone from Huawei can elaborate regarding the algorithm used in IUB interface.

Thanks,

agenov
2011-12-14, 05:55 PM
If possible can you please provide your current Huawei Iub configuration?

BR
Alex


Hi Satria,
Thanks a lot for your valuable reply, however as I stated it's not a problem in congestion of problem of VCC blocking due to max. number of connections as it is happening on the whole network, there's no single site having 2E1 on which we can have a throughput higher than 2.75Mbps while for Huawei they can reach 3.2Mbps! I guess the problem may be because in Huawei they don't have the same IUb dimensioning in NSN that divides it into VCCs some of them are dedicated and some are shared, however they use a different algorithm that may take into account all unused resources to be used whenever needed.
Please correct me if I'm wrong and I'd appreciate if someone from Huawei can elaborate regarding the algorithm used in IUB interface.

Thanks,