EDGE KPIs in NSN

EDGE Key Performance Indicators

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# Nokia Corporation 1 (30)

2003354Nokia GSM/EDGE BSS11.5 SystemDocumentation Update 1

The information in this documentation is subject to change without notice and describes only theproduct defined in the introduction of this documentation. This documentation is intended for theuse of Nokia's customers only for the purposes of the agreement under which the documentationis submitted, and no part of it may be reproduced or transmitted in any form or means without theprior written permission of Nokia. The documentation has been prepared to be used byprofessional and properly trained personnel, and the customer assumes full responsibility whenusing it. Nokia welcomes customer comments as part of the process of continuous developmentand improvement of the documentation.

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Copyright © Nokia Corporation 2005. All rights reserved.

2 (30) # Nokia Corporation dn7032527Issue 3 en


Contents

Contents 3

1 Changes in EDGE key performance indicators 5

2 EDGE key performance indicators (KPIs) 7

3 EDGE KPI categories 9

4 Network usage KPIs 11

5 Congestion KPIs 175.1 PDTCH congestion KPIs 175.2 Abis congestion KPIs 185.3 PCU congestion KPIs 195.4 Gb congestion KPIs 20

6 Quality KPIs 216.1 PDTCH quality KPIs 21

7 Mobility KPIs 25

8 Reference for used formulas 27

Related Topics 29

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Contents

1 Changes in EDGE key performanceindicators

Changes between releases BSS11.5 and BSS11.5 Update 1

The following key performance indicators (KPIs) have been removed:

. trf_208a

. trf_205a

. trf_162b

. trf_161b

. dap_4

The following KPIs have been added:

. trf_237c

. trf_234a

. dap_7b

The version of the following KPIs has been changed:

Old version New version

trf_212a trf_212b

trf_213a trf_213b

trf_214a trf_214b

trf_233 trf_233b

trf_235 trf_235a

frl_8 frl_8a

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Changes in EDGE key performance indicators

Reference for used formulas has been added.



2 EDGE key performance indicators (KPIs)

These are the Nokia recommendations for the EDGE key performance indicators(KPIs). KPIs for CS-3 and CS-4 are not included.

These definitions are subject to change. Nokia improves the definitions and thelist of KPIs according to received feedback and results from testing and fieldoperations.

A KPI is a value that presents some vital information about the network. TheKPIs are mapped directly from performance indicators (PIs), a formula of severalPIs, or directly from network counters.

Nokia has divided the EDGE KPIs into the following categories:

. Network usage

. Congestion

. Quality

. Mobility

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EDGE key performance indicators (KPIs)

3 EDGE KPI categories

Table KPI groups and formula names lists the key performance indicator (KPI)groups.

The last letter after the formula ID number is for version control. When smallimprovements to the formula are made, the last letter is incremented but theformula number remains unchanged. KPI users should always use the most recentversion of the formulas.

Table 1. KPI groups and formula names

KPI group Description Formula ID

Network usage DownlinkGPRSRLC payload trf_213b

Uplink GPRS RLC payload trf_212b

Downlink EGPRS RLC payload trf_215a

Uplink EGPRS RLC payload trf_214b

PS GPRS erlangs trf_237c

Number of uplink simultaneoususers

trf_231

Number of downlink simultaneoususers

trf_232

PDTCH congestion Downlink multislot allocationblocking

tbf_16

Downlink multislot soft blocking blck_33

Downlink TBFs per timeslot tbf_38c

Abis congestion Inadequate EDAP resources indownlink

dap_7b

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EDGE KPI categories

Table 1. KPI groups and formula names (cont.)

PCU congestion Territory upgrade rejections dueto a lack of PCU capacity

blck_32

Gb congestion Maximum received load % frl_8a

PDTCH quality Downlink GPRS RLC throughput trf_235a

Uplink GPRS RLC throughput trf_233b

Downlink EGPRS RLC through-put

trf_236

Uplink EGPRS RLC throughput trf_234a

Mobility Downlink TBF releases due toflush

tbf_36a

Most of the KPIs are combined to be common for one BTS. Abis, PCU, and Gbcongestion KPIs are related to the Abis interface (Dynamic Abis), BSC, and Gbinterface respectively. However, the BTS KPIs can be summed up (that is, overone BSC) to obtain the corresponding KPIs at the BSC level.



4 Network usage KPIsGPRS DL payload data (kbytes), S9PS (trf_213b)

Use:

Indicates all GPRS payload data in downlink.

Formula:

All GPRS DL payload data (kbytes) =

sum(rlc_data_blocks_dl_cs1 x 20

+ rlc_data_blocks_dl_cs2 x 30)

/1024

Counters from table(s):

p_nbsc_packet_control_unit

Unit:

kbytes

GPRS UL payload data (kbytes), S9PS (trf_212b)

Use:

Indicates all GPRS payload data in uplink.

Formula:

All GPRS UL payload data (kbytes) =

sum(rlc_data_blocks_ul_cs1 x 20

+ rlc_data_blocks_ul_cs2 x 30)

/1024



Unit:

kbytes

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Network usage KPIs

EGPRS DL payload data (kbytes), S10.5PS (trf_215a)

Use:

Indicates all EGPRS payload data in downlink.

Formula:

(sum over MCS-1 (xx) x 22 +

sum over MCS-2 (xx) x 28 +





sum over MCS-7 (xx/2) x 112 +


sum over MCS-9 (xx/2) x 148)

/1024

where xx =

(DL_RLC_BLOCKS_IN_ACK_MODE + DL_RLC_BLOCKS_IN_UNACK_MODE)


p_nbsc_coding_scheme

Unit:

kbytes

EGPRS UL payload data (kbytes), S10.5PS (trf_214b)

Use:

Indicates all EGPRS payload data in uplink.

Formula:

(sum over MCS-1 (xx) x 22 +






sum over MCS-7 (xx/2) x112 +


sum over MCS-9 (xx/2) x 148))

)/1024

where xx = (UL_RLC_BLOCKS_IN_ACK_MODE + UL_RLC_BLOCKS_IN_UNACK_MODE -

[ignor rlc data bl ul due bsn mcs n])

[ignor rlc data bl ul due bsn egprs] =



trf_204a

b.ignor_rlc_data_bl_ul_due_bsn * ------------------

trf_203 + trf_204a

[ignor rlc data bl ul due bsn mcs n] =

sum over MCSn (a.UL_RLC_Blocks_In_Ack_Mode

+ a.UL_RLC_Blocks_In_Unack_Mode)

[ignor rlc data bl ul due bsn egprs] * ------------------------------------------

sum over MCS1-9 (a.UL_RLC_Blocks_In_Ack_Mode

+ a.UL_RLC_Blocks_In_Unack_Mode)


p_nbsc_coding_scheme

Unit:

kbytes

PS traffic, S10.5 (trf_237c)

Use:

Detects the maximum amount of PS data traffic during the measurement period.

Formula:

PS Erlangs = max(UL PS Erlangs, DL PS Erlangs) =

Max((a.rlc_data_blocks_ul_cs1

+ a.rlc_data_blocks_ul_cs2

+ a.BAD_FRAME_IND_UL_CS1

+ a.BAD_FRAME_IND_UL_CS2

+ a.BAD_FRAME_IND_UL_UNACK

+ a.rlc_mac_cntrl_blocks_ul

+ [ignor rlc data bl ul due bsn gprs]

+ sum over MCS0..6 of (b.ul_rlc_blocks_in_ack_mode

+ b.ul_rlc_blocks_in_unack_mode

+ b.bad_rlc_valid_hdr_ul_ack + b.bad_rlc_valid_hdr_ul_unack

+ b.bad_rlc_bad_hdr_ul_ack + b.bad_rlc_bad_hdr_ul_unack)

+ sum over MCS7..9 of (b.ul_rlc_blocks_in_ack_mode

+ b.ul_rlc_blocks_in_unack_mode

+ b.bad_rlc_valid_hdr_ul_ack + b.bad_rlc_valid_hdr_ul_unack

+ b.bad_rlc_bad_hdr_ul_ack + b.bad_rlc_bad_hdr_ul_unack)/2)

---------------------------------------------------------------

period_duration*60*50

(a.rlc_data_blocks_dl_cs1

+ a.rlc_data_blocks_dl_cs2

+ a.retra_rlc_data_blocks_dl_cs1

+ a.retra_rlc_data_blocks_dl_cs2

+ a.rlc_mac_cntrl_blocks_dl

+ sum over mcs1..6 of (b.dl_rlc_blocks_in_ack_mode

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Network usage KPIs

+ b.dl_rlc_blocks_in_unack_mode + b.retrans_rlc_data_blocks_dl)

+ sum over mcs7..9 of (b.dl_rlc_blocks_in_ack_mode

+ b.dl_rlc_blocks_in_unack_mode + b.retrans_rlc_data_blocks_dl)/2)

----------------------------------------------------------------------

period_duration*60*50)

[ignor rlc data bl ul due bsn gprs] =

trf_203

a.ignor_rlc_data_bl_ul_due_bsn * ------------------

trf_203 + trf_204a


a = p_nbsc_packet_control_unit

b = p_nbsc_coding_scheme

Unit:

Erlangs

Average number of UL simultaneous users, S10.5 (trf_231)

Use:

Provides the average number of simultaneous users in uplink. The formula isapplicable for BTS and area levels.

Formula:

sum(ave_dur_ul_tbf_sum)

-------------------------------------------------------------------

100 x avg(period_duration) x count(distinct period_start_time) x 60


P_NBSC_PACKET_CONTROL_UNIT

Unit:

Number of users

Average number of DL simultaneous users, S10.5 (trf_232)

Use:

Provides the average number of simultaneous users in downlink. The formula isapplicable for BTS and area levels.

Formula:

Sum(ave_dur_dl_tbf_sum)



-------------------------------------------------------------------

100 x avg(period_duration) x count(distinct period_start_time) x 60


P_NBSC_PACKET_CONTROL_UNIT

Unit:

Number of users

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Network usage KPIs

5 Congestion KPIs

5.1 PDTCH congestion KPIs

DL mslot allocation blocking, S9PS (tbf_16)

Use:

If blocking happens regularly, either the territory (CS traffic low) or TCHcapacity (CS traffic high) needs to be expanded.

Note

If the statistics show that there is blocking but no upgrade requests yet, the reasonmay be that the territory is smaller than defined in the default settings (CS use).The PCU will not make an upgrade request. This is because the CSW side returnsthe default channels back to the PS territory as soon as the CSW load allows this.

Formula:

sum(NO_RADIO_RES_AVA_DL_TBF)

100 x -------------------------------------------------------- %

sum(req_1_TSL_DL + req_2_TSL_DL + req_3_TSL_DL

+ req_4_TSL_DL + req_5_8_TSL_DL)



DL multislot soft blocking %, S10.5 PS (blck_33)

Use:

Indicates the ratio of unserved timeslots requests to all requests in downlink.

Formula:

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Congestion KPIs

100 - msl_6



For the msl_6 definition, see Ratio of served GPRS DL TSL requests, S9PS(msl_6).

Average DL TBF per timeslot, S9PS (tbf_38c)

Use:

Indicates how many downlink TBFs there are, on average, per timeslot.

Formula:

sum(aver_tbfs_per_tsl_dl_sum)

-----------------------------------

sum(aver_tbfs_per_tsl_dl_den) x 100



5.2 Abis congestion KPIs

Inadequate EDAP resources in DL, S11PS (dap_7b)

Description:

Time per kilobytes when the adequacy of requested EDAP resources cannot begranted for a scheduled downlink TBF in the BTSs where EGPRS is enabled.

Use:

Indicates time per kilobytes when the available downlink EDAP resources areinadequate.

Note

This formula cannot be used with PCU2, because CS-3 and CS-4 are notincluded.

Formula:



Sum (DL_Indadeq_Time_minutes)

/ Sum (DL GPRS payload_kbyte + DL EGPRS payload_kbyte)

=

sum( a.dl_tbfs_with_inadeq_edap_res) / (50 x 60)

-------------------------------------------------

sum over BTS with EGENA = Y

( rlc_data_blocks_dl_cs1 x20

+ rlc_data_blocks_dl_cs2 x 30

+ sum over MCS-1 (xx) x 22






+ sum over MCS-7 (xx/2) x 112

+ sum over MCS-8 (xx/2) x 136

+ sum over MCS-9 (xx/2) x 148)

/ 1024

where xx = (dl_rlc_blocks_in_ack_mode + dl_rlc_blocks_in_unack_mode)


a = p_nbsc_dynamic_abis

b = p_nbsc_packet_control_unit

c = p_nbsc_coding_scheme

Unit:

Minutes per kbyte

5.3 PCU congestion KPIs

Territory upgrade rejection due to PCU capacity %, S9PS (blck_32)

Use:

Indicates the ratio of territory upgrade requests that result in rejection because ofPCU capacity.

Formula:

sum(gprs_ter_ug_rej_due_lack_pcu)

100 x ----------------------------------%

sum(gprs_ter_upgrd_req)


p_nbsc_traffic

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Congestion KPIs

5.4 Gb congestion KPIs

Maximum received load %, S9PS (frl_8a)

Use:

Indicates the load percentage of the frame relay bearer for incoming data from theSGSN.

Formula:

sum(8 x (dlci_1_bytes_rec

+ dlci_2_bytes_rec

+ dlci_3_bytes_rec

+ dlci_4_bytes_rec

+ dlci_5_bytes_rec)/(period_duration x 60))

100 x ------------------------------------------------ %

sum per frbc over all unlocked child nsvc

(c_nsvc.committed_info_rate x 16);

frbc object_instance = bearer_id in p_nbsc_frame_relay


p_nbsc_frame_relay



6 Quality KPIs

6.1 PDTCH quality KPIs

Average effective ACK GPRS DL throughput per used TSL, S10PS (trf_235a)

Use:

Indicates the impact of the radio link quality on net data rate per used timeslot,taking into account the retransmissions and coding scheme selection. The lowerthe value, the poorer the radio link quality. This causes retransmissions and theuse of lower coding schemes.

The numerator does not contain the RLC header bytes; neither does the MACheader. This is because the aim is to count the data volume from as close to theuser’s point of view as possible.

Formula:

GPRS ACK DL payload data in (kilobits)

---------------------------------------- =

GPRS ACK DL time for data transfer (sec)

sum((RLC_data_blocks_DL_CS1 rlc_data_blocks_dl_unack) x 20

+ a.RLC_data_blocks_DL_CS2 x 30) x 8 /1000

-----------------------------------------------------------

sum(rlc_data_blocks_dl_cs1

- rlc_data_blocks_dl_unack

+ rlc_data_blocks_dl_cs2

+ RETRA_RLC_DATA_BLOCKS_DL_CS1

+ RETRA_RLC_DATA_BLOCKS_DL_CS2) /50



Unit:

kbit/sec/TSL

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Quality KPIs

Average effective ACK GPRS UL throughput per used TSL, S11.5PS(trf_233b)

Use:



The denominator is built on the fact that one timeslot can carry 50 RLC blocksper second.

Formula:

GPRS UL payload ACK data in (kilobits)

--------------------------------------- =

GPRS UL time for ACK data transfer (sec)

sum((a.rlc_data_blocks_ul_cs1

- a.rlc_data_blocks_ul_unack) x 20

+ a.rlc_data_blocks_ul_cs2 x 30) x 8 /1000

------------------------------------------

sum(a.rlc_data_blocks_ul_cs1

- a.rlc_data_blocks_ul_unack

+ a.rlc_data_blocks_ul_cs2

+ a.retra_data_blocks_ul_cs1

+ a.retra_data_blocks_ul_cs2) /50




Unit:

kbit/sec/TSL

Average effective ACK GPRS DL throughput per used TSL, S10PS (trf_236)

Use:





Formula:

EGPRS ACK DL payload data in (kilobits)

---------------------------------------- =

EGPRS ACK DL time for data transfer (sec)

(sum over MCS-1 (xx) x 22








+ sum over MCS-9 (xx) x 74) x 8/1000

-------------------------------------

sum over msc1…6 of (yy)/50

+ sum over msc7…9 of (yy)/2/50

where

xx = b.dl_rlc_blocks_in_ack_mode

yy = b.dl_rlc_blocks_in_ack_mode

+ b.retrans_rlc_data_blocks_dl



Unit:

kbit/sec/TSL

Average effective ACK GPRS UL throughput per used TSL, S10PS (trf_234a)

Use:



The denominator is built on the fact that one timeslot can carry 50 RLC blocksper second.

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Quality KPIs

Formula:

EGPRS UL payload ACK data in (kilobits)

--------------------------------------- =

EGPRS UL time for ACK data transfer (sec)

(sum over MCS-1 (xx) x 22

+ sum over MCS-2 (xx)x 28







+ sum over MCS-9 (xx) x 74) x 8/1000

-------------------------------------

sum over MCS1..6 of (yy)/50

+ sum over MCS7..9 of (yy)/2 /50

where

xx = b.ul_rlc_blocks_in_ack_mode - [ignor rlc data bl ul due bsn mcs n ack]

yy = b.ul_rlc_blocks_in_ack_mode - [ignor rlc data bl ul due bsn mcs n ack]

+ b.retrans_rlc_data_blocks_ul

[ignor rlc data bl ul due bsn egprs] =

trf_204a

a.ignor_rlc_data_bl_ul_due_bsn * ------------------

trf_203 + trf_204a

[ignor rlc data bl ul due bsn egprs ack] =

sum over MCS1-9

(b.UL_RLC_Blocks_In_Ack_Mode)

[ignor rlc data bl ul due bsn egprs] * ----------------------------------

sum over MCS1-9

(b.UL_RLC_Blocks_In_Ack_Mode +

b.UL_RLC_Blocks_In_Unack_Mode)

[ignor rlc data bl ul due bsn mcs n ack] =

sum over MCSn


[ignor rlc data bl ul due bsn egprs ack] * -------------------------------

sum over MCS1-9





Unit:

kbit/sec/TSL



7 Mobility KPIsDL TBF releases due to flush %, S10.5 PS (tbf_36a)

Use:

Indicates by cell reselection that there is mobility from this cell to other cells. Cellreselection affects the throughput.

Note

Some abnormal releases are not shown in any release counters (those are includedin establishment), but this has no impact on this formula.

Formula:

sum (DL_TBF_REL_DUE_TO_FLUSH)

100 x ---------------------------------------------------------------- %

sum(Nbr_of_DL_TBF- DL_TBF_Establishment_Failed -

DL_EGPRS_TBF_REL_DUE_NO_RESP)



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Mobility KPIs

8 Reference for used formulas

The KPI described here has been used in the previous benchmark KPI definitions.

Ratio of served GPRS DL TSL requests, S9PS (msl_6)

Use:

Indicates the ratio of timeslot allocations to requests in downlink.

Formula:

sum(alloc_1_TSL_DL + 2 x alloc_2_TSL_DL

+ 3 x alloc_3_TSL_DL

+ 4 x alloc_4_TSL_DL)

100 x -------------------------------------------------------------------- %

sum(req_1_TSL_DL + 2 x req_2_TSL_DL + 3 x req_3_TSL_DL + 4 x req_4_TSL_DL)



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Reference for used formulas

Related Topics


EDGE KPI categories

Network usage KPIs

Congestion KPIs

Quality KPIs

Mobility KPIs


EDGE KPI categories


Network usage KPIs


Congestion KPIs


Quality KPIs


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Related Topics

Mobility KPIs






EDGE KPIs in NSN

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