Smartphones and Network Signalling Load 20110927

1 © Nokia Siemens Networks / Smartphones and Network Signalling Load / Atinan Tumsatan

Smartphone and network signaling load Bandung September 22nd – 23rd , 2011


Packet Data Transfer States

3 © Nokia Siemens Networks / Smartphones and Network Signalling Load/ Atinan Tumsatan

UTRA RRC state transitions

Inactivity timer

Inactivity timer

Inactivity timer

PCH/URA

DCH/HSDPCH

Cell_FACH

>200 mA

>100 mA

< 5 mA

< 5 mA

30 signaling

messages

(2 s)

12 signaling

messages

(<0.5 s) 3 msgs 2 msgs

6 msgs 6 msgs

4 msgs

Idle

T1

T2

T3


States within UTRA RRC connected mode


States within UTRA RRC connected mode


States transition Cell_DCH

Transition from Cell_DCH state to Cell_FACH state

• inactivity during service establishment phase

• SRBs and PS RT/NRT RBs inactivity after a packet call

• SRB inactivity and NRT RBs release level throughput

• SRBs inactivity and MAC-d flow low utilization or low throughput

• last CS RAB released (Iu-PS connection exists)

• loss of FP-level synchronization (transport bearer synchronization failure)

• delay of FP-level frames when UE is in SHO

• loss of L1 synchronization (radio link failure detected by the UE)

• L2 signaling error (RLC unrecoverable error) detected in the Cell_DCH state

Transition from Cell_DCH state to PCH states

• Long inactivity of NRT RB(s) detected

• Release of RT RB and inactive NRT RB(s) and/or signaling connection

• HW resources at low level

• Rel8 Fast Dormancy


Packet Data Transfer States RNC parameters and timers: CELL_DCH state

Timers for supervising RB and SRB

activity during service establishment

UL_DLcapacityReqWait = 5 sec

SignallingLinkInactivityTimer = 2 sec

* Only uplink parameters are listed here, corresponding timers are also defined for downlink direction.

InactivityTimerUplinkDCH384* = 2 sec

InactivityTimerUplinkDCH320* = 2 sec

InactivityTinerUplinkDCH256* = 2 sec






CellDCHtestTmr = 0 minute

ToCellFACHinTest = 1(Yes)

InactDetForStreamingRB = 1(In use)

Release threshold parameters for the

NRT DCH utilisation measurement

DCHutilRelThrUL = 256 bps

DCHutilRelThrDL = 256 bps

MACdflowutilRelThr = 256 bps

MACdflowutilTimetoTrigger = 0 sec

MACdflowthroughputRelThr = 0 bps

MACdflowthroughputTimeToTrigger = 5 sec

MACdflowthroughputAveWin = 3 sec

EDCHMACdFlowThroughputAveWin = 3 sec

EDCHMACdFlowThroughputRelThr = 256 bps

EDCHMACdFlowThroughputTimeToTrigger = 5 sec

HSDSCHGuardTimerLowThroughput = 30 sec

Timers and parameters for supervising SRBs and PS RT/NRT RBs inactivity in Cell_DCH

state


Cell_FACH state to Cell/URA_PCH state

UL/DLActivationTimer = 2000 ms

ExtendedULDLActivationTmr = 0 sec

SignConnActivitySupervision = 1 minute

CVUserInactInSignConnRel = 1(Yes)

Packet Data Transfer States RNC parameters and timers: CELL_FACH state

Cell_FACH state to Cell_DCH state

TrafVolThresholdULLow = 128 bytes

TrafVolTimeToTriggerUL = 0 ms

[WCEL] TrafVolThresholdDLLow = 128 bytes

TrafVolTimeToTriggerDL = 0 ms


Packet Data Transfer States RNC parameters and timers: CELL/URA_PCH states

Paging (Cell/URA_PCH to Cell_FACH)

PageRep1stInterv = 700ms

PageRep2ndInterv = 2000ms

UE timers and constants (on which the

corresponding RNC timers are based)

for “Out of Service Area” detection in

Cell_FACH and Cell/URA PCH states

T316 = 30 seconds

T317 = 180 seconds

T305 = 30 minutes

T307 = 30 seconds

T302 = 2000 ms

N302 = 7

Cell/URA_PCH to Cell_DCH

CUCforPCHtoDCHallowed = 1(true)

[WCEL] CUCEcNoThreshold = 31 (~ -9dB)

[WCEL] CUCRSCPThreshold = -92 dBM

[WCEL] RACHIntraFreqMesQuant = 0 (EcNo)

[System-defined]TrafVolThrDLLowGTP = 128 bytes

Cell_FACH or Cell_PCH to URA_PCH

MaxCellReselections = 3 times

CellReselectionObservingTime = 16 minutes

Timer for user inactivity detection in

Cell_PCH state

MSActivitySupervision = 29 minutes


RAN2136 Fast Dormancy


RAN2136 Fast Dormancy

Brief description:

• Fast dormancy is an 3GPP Rel.8 feature optional for UEs.

• The purpose of this feature is to reduce the signaling load between the 3G network and the UE and to save the UE’s battery life.

• The UE informs the network when a PS data transmission ends. The network changes the UE state directly to Cell_PCH or URA_PCH state, which lowers the UE battery consumption considerably, instead of staying in Cell_DCH or Cell_FACH state.

• If the UE needs to send or receive data the required signaling from Cell/URA_PCH state is only a fraction of the signaling needed in starting from IDLE mode.\

Benefits:

• [User] : UE works longer without battery recharge because of lower battery consumption.

• [Operator] : saves significantly on the signaling load compared to going to IDLE mode.

PCH states have to be supported in the RNC before the Fast Dormancy

feature can be activated ([RNC]MSActivitySupervision value has to be >0).


The UE sends SIGNALLING CONNECTION RELEASE INDICATION message with

"Signalling Connection Release Indication Cause“ with the cause value UE Request PS Data

session end to the RNC. The RNC receives the message and starts immediately the UE

state change from Cell_DCH to Cell_PCH or URA_PCH state.

SCRI with the cause value

“UE Request PS Data session end”

UE sends SCRI

SCRI = Signalling Connection Release Indication

UE sends SCRI

RAN2136 Fast Dormancy Functional Description (1/2)

Inactivity timer

Inactivity timer

Inactivity timer

PCH

Idle

DCH/HSDPCH

Cell_FACH

>200 mA

>100 mA

< 5 mA

< 5 mA

Idle

Inactivity timer

Inactivity timer

Inactivity timer

PCH

Idle

DCH/HSDPCH

Cell_FACH

>200 mA

>100 mA

< 5 mA

< 5 mA

Idle

3GPP R8 or later UEs

3GPP R7 or earlier UEs

RAN2136 Fast Dormancy is activated


RAN2136 Fast Dormancy Functional Description (2/2)

• There is a new UE Signalling Connection Release Indication Cause value in SIGNALLING CONNECTION RELEASE INDICATION message. This new cause is UE Request PS Data session end and it indicates to the network that the UE has concluded active PS data transfer.

• When the RNC receives the cause value, it starts immediately the UE state change from Cell_DCH state to Cell_PCH or URA_PCH state by sending RADIO BEARER RECONFIGURATION message to the UE.


RAN2136 Fast Dormancy Signalling messages needed vs. RRC states

RRC NBAP RANAP ALCAP

From Idle_mode to Cell_DCH 12 5 7 6

From Cell_PCH to Cell_DCH 5 3 0 4

Number of messages


Software Requirements

Network Hardware Requirements

• This feature does not require any new or additional HW.

Interdependencies between Features

• PCH states have to be supported in the RNC before the Fast

Dormancy feature can be activated.

RAN2136 Fast Dormancy Requirements


• There’s no parameter to enabled/disable Fast Dormancy in

RU20. It’s possible in RU30.

• Cell_PCH state is prerequisite for Fast Dormancy to be activated ([RNC] MSActivitySupervision > 0).

Parameter settings

RAN2136 Fast Dormancy Parameters


Blackberry


Cell_DCH

Cell_PCH

Cell_PCH & NCFD are Activated

BB Torch 2

RAN2136 Fast Dormancy Test results from Live network

UE setting: use Default (Rel8) Fast Dormancy


Cell_DCH

Idle

RAN2136 Fast Dormancy Test results from Live network

BB Torch 2


UE setting: Use Rel99 Fast Dormancy


iPhone 4 iOS 4.3


Cell_FACH

Cell_PCH


Log file

iPhone 4 iOS 4.3.5

RAN2136 Fast Dormancy Test results in Test Bed


Cell_FACH

Idle

Cell_PCH & NCFD are Deactivated

Log file RAN2136 Fast Dormancy Test results in Test Bed

iPhone 4 iOS 4.3.3

Smartphones and Network Signalling Load 20110927

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