spd huawei eran3.0 admission and congestion control feature introduction 20120529 a 1.0

8/10/2019 SPD Huawei ERAN3.0 Admission and Congestion Control Feature Introduction 20120529 a 1.0

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HUAWEI TECHNOLOGIES CO., LTD.

www.huawei.com

Huawei Confidential

Security Level: internal

Huawei eRAN3.0Admission and Congestion

Control FeatureIntroduction


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HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 2

Admission and Congestion Control Features Roadmap

eRAN 2.x

(2011Q2)

eRAN 1.0

(2009Q2)

Basic admission control

based on power, RButilization and QoS

satisfaction ratio

S1 transmission resource

check

Independent HOthreshold

Redirection due to

admission failure

Overload Control

Admission threshold per

QCI

Min-GBR configuration for

non-GBR service per QCI

Pre-emption

Differentiation AdmissionControl

Pre-emption based on

user number

eRAN 3.0

(2012Q2)


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Content

Admission Control

Overload Control

Parameter Introduction

Algorithm Relationship

Application Scenario

Performance Statistic & Maintenance


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Admission Control Strategy

Huawei two stage admission control strategy

Stage 1: Resource Allocation & Check (HW,TNL, Overload indicator, downlinkpower)

Stage 2: QoS Satisfaction Ratio-basedadmission check (both uplink anddownlink GBR)

Different types of service requests handling

Lower threshold provided for HO request, comparing with new service request; Admission thresholds (not applicable to HO request) configured per user priority

(Gold / Silver / Bronze levels mapping from ARP).

Resource Allocation

& Check

QoSSatisfaction

Ratio Check

Stage 2: UL/DLadmission check

Stage 1: Resource

availability

Emergency

call

Admission

Result

New service request

HO request

(higher priority)

New service request

HO request

(higher priority)

SRB request

Resource Allocation

& Check


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Admission Flow Chart (1/2)

See next

slide

If system is overloaded, no

service (except SRB and

emergency call) can be admitted.

UE capability check based on GBR ,

considering Maximum number of bits

of an UL/DL-SCH transport block

transmitted within a TTI

The following resources will be

checked:

1. Transport (S1) resources;

2. HW limit: CPU processing,

maximum users per cell;

3. System overload indicator (via

load control)

4.PUCCH Resource5. Downlink Power.

New or HO

Service request

UE capability meets

the requirements?Reject

Emergency call (e.g.

911)?

Yes

Resource limited?

No

DL Admission

No

Accept? UL Admission

Accept?

Yes

Reject /

Redirection

No

No

Yes

No

Admitted

Yes

Yes

Preemption

Successful?

No

Yes


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New /HO service request

RB utilization is below

threshold and not power-

limit?

GBR service QoS Satisfaction ratio

evaluation

Num of Non-GBR bearers Admit based on the QoS

satisfaction ratio threshold or

num of Non-GBR bearers

Reject/redirect

Admit

Yes

Yes

No

Yes

checking RB utilization

of GBR services

Yes

premption

No

No

No

Admission Flow Chart (2/2)

Reserve resource for non-

GBR services:

State the resource consumed

by GBR services, if it is higher

than the limit threshold, GBR

services should execute

preemption among GBR

services rather than continueto utilize the remained

resource reserved for Non-

GBR services Kick off low priority service so

as to let high priority service

be admitted

DRB admission failure will

trigger preemption process.

Signal, IMS, urgent call cant

be preempted.

Need to release enough low

priority in-system services so

as to satisfy the GBR or min-

GBR of new service with high

priority.

To reduce theunnecessary non-GBRservices of one user areadmitted into the systemwhen the users AMBRlimitation is reached Released users will be

allocated with different

frequency through RRC signal.

Unsuccessfully preemptedusers except HO users, and

preempted users, can be

redirected.


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Checking RB utilization of GBR services Objective

Guarantee that GBR services will not exhaust all of the cell resource and Non-GBR services will not be

subjected to severe starvation.

Benefits Can reduce the risk that Non-GBR services are subjected to severe starvation

Functionalities

Principle

Stat the resource consumed by GBR services, if it is higher than the limit threshold, GBR services should

execute preemption among GBR services rather than continue to utilize the remained resource reserved for

Non-GBR services.

trigger

The function can be switched on\off.

If switched on, each GBR data radio bearer setup request arrives, this checking action will be executed.

Key parameter

GbrUsedRbCheckSwitch: the switch of function

GbrSerHighProportion ::threshhold represents that GBR services RB utilization ratio is high

GbrSerLowProportion: threshhold represents that GBR services RB utilization ratio is low


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Preemption Objective

Guarantee that Services with high priority can still access a congested network.

Benefits

Produce the diversity for service-access.

Functionalities

Principle

DRB admission failure will trigger preemption process.

Signal, IMS, urgent call cant be preempted.

Need to release enough low priority in-system services so as to satisfy the GBR of new service with high

priority.

trigger

Preemption can be switched on/off.

If switched on, when fail to admitted, this function will be executed

Key parameter

PreemptionSwitch: the switch of function

PreemptionArpThd: ARP threshold which means that all services with lower ARP than the threshold may be

preempted.

UnPreemptedServSet: represents which QCIs services cant be preempted


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Redirection

Objective

Guarantee that released users can access network from other frequency when services are requested

once again.

Benefits

Can reduce the risk that current cell becomes overload again.

Functionalities

Principle

Released users will be allocated with different frequency through RRC signal.

Unsuccessfully preempted users except HO users, and preempted users, can be redirected.

Trigger

Redirection can be switched on\off.

Key parameters

RedirecAlgoSwitch: the switch of function


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HUAWEI TECHNOLOGIES Co., Ltd. HUAWEI Confidential Page 11

QoS Satisfaction Ratio based Admission Decision

Provide independent threshold for HO request, per QCI.

Provide different thresholds based on user priority (Gold / Silver / Bronze

levels mapping from ARP) for new service request, per QCI.

HOThr

Satisfaction Ratio

GoldThr

SilverThr

BronzeThr

QcixHoThd

OffsetGold

Offset Silver

OffsetBronze

Time

HOThr

GoldThr SilverThr BronzeThr

100%

DL Q S S ti f ti R ti Ch k


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DL QoS Satisfaction Ratio Check

QoS satisfaction ratio is evaluated based on the QoS Class Identifier (QCI) for

the call to be admitted.

Each QCI has its corresponding QoS satisfaction criteria.

Non-GBR service neednt to be checked.

Emergency call neednt to be checked.

Mapping between QCI and evaluation standard for downlink services is

provided in default.

QCI Service Type Evaluation Standard

1 Conversational Meet the Guaranteed bit rate

2 Conversational Video (Live

Streaming)

Meet the Guaranteed bit rate

3 Real Time Gaming Meet the Guaranteed bit rate

4 Non-Conversational Video

(Buffered Streaming)

Meet the Guaranteed bit rate

UL Q S S ti f ti R ti Ch k


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UL QoS Satisfaction Ratio Check

QoS satisfaction ratio check in the uplink:

QoS satisfaction ratio is evaluated based on the Logical Channel Group (LCG) for the call to

be admitted.

Each LCG has its corresponding QoS satisfaction criteria.

Mapping between LCG and evaluation standard for uplink services is provided in default.

The nine QCIs are mapped to the four logical channel groups:

Logical Channel Group Evaluation Standard

1 Meet the Guaranteed bit rate

2 Meet the Guaranteed bit rate

Logical Channel Group QCI Service Type

0 QCI=5 and SRB

bearer

Control-plane transmission and IMS

signaling1 QCI=1 VoIP service

2 QCI=24 GBR service


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Content

Admission Control

Overload Control






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Overload Control Overview

Objective

Guarantee services QoS in the system on cell level

Benefits

Prevent system from being unstable due to overload and improve system

stability

Guarantee the QoS in the system by effectively alleviate the system overload

Functionalities Triggered when an overload situation occurs and based on RB Utilization and

QoS Satisfaction Ratio

Overload Control actions

GBR Downgrading

Service Release / Redirection

Overload Control Procedure


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QoS satisfaction cannot be met

and RB usage high / DL Tx power

limited

Service Release /

Redirection

Priority-based GBR

Downgrading

Overload Control Procedure

Two actions to alleviate the

system load effectively

Proportion reducing GBR of GBR

services according to priority

Only if redirect/release is enabled

Overload Triggered

If no connection can be redirected/released

These two actions are

optional to Operators.

Priority based GBR Downgrading


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Priority-based GBR Downgrading

Objective

Guarantee that GBR services with different priority are downgraded with different percent when

network becomes congested.

Benefits

GBR service with different priority can be downgraded with different percent.

Functionalities

Principle

Set different downgrading percent for golden/silver/bronze services respectively. Thengolden/silver/bronze services can be downgraded according to preset percent.

trigger

If service release switch off, the function will be executed

If service release switch on but without enough services to be released to reduce load, the

function will be executed.

Key parameter GoldGbrCongProportion: the downgrading proportion for gold GBR bearers.

SilverGbrCongProportion : the downgrading proportion for silver GBR bearers.

CopperGbrCongProportion: the downgrading proportion for copper GBR bearers.


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Content

Admission Control

Overload Control






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Key Parameters (1)

Id Name Description Range Recommended

Value

MML

RacAlgoS

witch

RAC

algorithm

switch

Indicates the switches used to enable or

disable the admission and load control

algorithms.

DlSwitch, UlSwitch,

GbrUsageSwitch,

DlLdcSwitch, UlLdcSwitch,

RelDrbSwitch,

PreemptionSwitch

DlSwitch:Off

UlSwitch:Off

GbrUsageSwitch:Off

DlLdcSwitch:Off

UlLdcSwitch:Off

RelDrbSwitch:Off

PreemptionSwitch:Off

MOD

CELLALGO

SWITCH

GoldServic

eArpThd

Gold

service arp

threshold

Indicates the Allocation and Retention Priority

(ARP) threshold for the Golden-level services.

A service is defined as a Golden-level service

if its ARP value is smaller than this threshold.

GUI value range: 1~15 5 MOD

CELLRACT

HD

SilverServiceArpThd

Silverservice arp

threshold

Indicates the Allocation and Retention Priority(ARP) threshold for the Silver-level services. A

service is defined as a Silver-level service if its

ARP value is smaller than or equal to the value

of this parameter and is larger than the value

of GoldServiceArpThd.


CELLRACT

HD

Qci1HoThd QCI1

handover

admission

threshold

Indicates the admission threshold for the

handed-over service with QCI of 1. This

threshold applies to both UL and DL.

If the satisfaction rate of services with QCI of 1

is above or equal to this threshold, thehanded-over service with QCI of 1 can be

admitted.

If the satisfaction rate of services with QCI of 1

is below this threshold, the handed-over

service with QCI of 1 cannot be admitted.


CELLRACT

HD


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Key Parameters (2)

Id Name Description Range Recommended

Value

MML

Qci2HoThd QCI2 handover

admission

threshold

Indicates the admission threshold for the handed-over service

with QCI of 2. This threshold applies to both UL and DL.

If the satisfaction rate of services with QCI of 2 is above or

equal to this threshold, the handed-over service with QCI of 2

can be admitted.

If the satisfaction rate of services with QCI of 2 is below this

threshold, the handed-over service with QCI of 2 cannot be

admitted.

GUI value

range:

10~99

90 MOD

CELLALGOS

WITCH


admission

threshold


with QCI of 3. This threshold applies to both UL and DL.If the satisfaction rate of services with QCI of 3 is above or

equal to this threshold, the handed-over service with QCI of 3

can be admitted.



admitted.

GUI value

range:

10~99

90 MOD

CELLRACTH

D


admission

threshold


with QCI of 4. This threshold applies to both UL and DL.

If the satisfaction rate of services with QCI of 4 is above or

equal to this threshold, the handed-over service with QCI of 4can be admitted.



admitted.

GUI value

range:

10~99

90 MOD

CELLRACTH

D

(3)


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Key Parameters (3)

Id Name Description Range Recommen

ded Value

MML

NewGold

ServiceOf

fset

Gold new

service

admission

threshold

offset

Indicates the offset for admission of new Gold-level services. The

value of this parameter applies in both UL and DL. New Gold-level

services and handed-over services with QCI N can be admitted if both

the following conditions are met: (1) The satisfaction rate of services

with QCI N is higher than or equal to the sum of this offset and the

admission threshold for the handed-over services with QCI N; (2) The

satisfaction rate of services with any other QCI is higher than the

corresponding admission threshold for the handed-over services with

that QCI. If the satisfaction rate of services with any QCI is lower than

its corresponding admission threshold for handed-over services with

that QCI, the new services cannot be admitted.

GUI

value

range:

0~90

5 MOD

CELLALGOS

WITCH

NewSilver

ServiceOf

fset

Silver new

service

admission

threshold

offset

Indicates the admission threshold for the handed-over service with

QCI of 3. This threshold applies to both UL and DL.

If the satisfaction rate of services with QCI of 3 is above or equal to

this threshold, the handed-over service with QCI of 3 can be admitted.

If the satisfaction rate of services with QCI of 3 is below this threshold,

the handed-over service with QCI of 3 cannot be admitted.

GUI

value

range:

10~99

5 MOD

CELLRACTH

D

K P t (4)


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Key Parameters (4)


ded Value

MML

NewCopp

erService

Offset

Bronze new

service

admission

threshold

offset

Indicates the offset for admission of new Bronze-level services. The

value of this parameter applies in both UL and DL. New Bronze-level

services and handed-over services with QCI N can be admitted if both

the following conditions are met: (1) The satisfaction rate of services

with QCI N is higher than or equal to the sum of this offset and the

admission threshold for the handed-over services with QCI N; (2) The

satisfaction rate of services with any other QCI is higher than the

corresponding admission threshold for the handed-over services with

that QCI. If the satisfaction rate of services with any QCI is lower than

its corresponding admission threshold for handed-over services with

that QCI, the new services cannot be admitted.

GUI

value

range:

10~99

5 MOD

CELLRACTH

D

Qci1Cong

Thd

QCI1 congest

threshold

Indicates the congestion threshold for services with QCI of 1. This

threshold applies to both UL and DL.If the satisfaction rate of services with QCI of 1 in the cell becomes

lower than this threshold, the services with QCI of 1 enter the

congested state.

If the satisfaction rate of services with QCI of 1 in the cell becomes

higher than the sum of this threshold and the congestion relief offset,

the services with QCI of 1 leave the congested state.

GUI

valuerange:

10~99

65 MOD

CELLRACTH

D

Qci2Cong

Thd

QCI2 congest

threshold




lower than this threshold, the services with QCI of 2 enter thecongested state.




GUI

value

range:

10~99

65 MOD

CELLRACTH

D

K P t (5)


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Key Parameters (5)


ded Value

MML

Qci3Cong

Thd

QCI3 congest

threshold



If the satisfaction rate of services with QCI of 3 the cell becomes


congested state.




GUI

value

range:

10~99

65 MOD

CELLRACTH

D

Qci4Cong

Thd

QCI4 congest

threshold





congested state.If the satisfaction rate of services with QCI of 4 in the cell becomes



GUI

value

range:

10~99

65 MOD

CELLRACTH

D

GoldGbrC

ongPropo

rtion

Gold-level GBR

service

congest

scheduler

proportion

Indicates the rate reduction proportion for Gold-level GBR services.

When congestion occurs, the rate that the scheduling algorithm

provides for Gold-level GBR services (except VoIP services) is the

product of GBR and this proportion.

GUI

value

range:

1~100

90 MOD

CELLRACTH

D

SilverGbrCongProp

ortion

Silver-levelGBR service

congest

scheduler

proportion

Indicates the rate reduction proportion for Silver-level GBR services.When congestion occurs, the rate that the scheduling algorithm

provides for Silver-level GBR services (except VoIP services) is the

product of the GBR and this proportion.

GUIvalue

range:

1~100

90 MOD

CELLRACTH

D

K P t (6)


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Key Parameters (6)


ded Value

MML

CopperGb

rCongPro

portion

Bronze-level

GBR service

congestscheduler

proportion

Indicates the rate reduction proportion for Bronze-level GBR services.

When congestion occurs, the rate that the scheduling algorithm

provides for Bronze-level GBR services (except VoIP services) is theproduct of GBR and this proportion.

GUI

value

range:1~100

90 MOD

CELLRACTH

D

GbrRbUs

edHighTh

d

GBR used

resource high

proportion

threshold

Indicates the threshold for high PRB usage by GBR services. The

value of this parameter is expressed in percentage and applies to

both UL and DL. If the MAC layer detects that the PRB usage by GBR

services exceeds the threshold, the usage is high. In this situation,

new GBR services are not admitted if GbrUsageSwitch under the

RacAlgoSwitch parameter is turned on.

GUI

value

range:

1~100

95 MOD

CELLRACTH

D

GbrRbUs

edLowTh

d

GBR used

resource low

proportion

threshold

Indicates the threshold for low PRB usage by GBR services. The

value of this parameter is expressed in percentage and applies to

both UL and DL. If the MAC layer detects that the PRB usage by GBR

services falls below the threshold, the usage is considered to be low.

GUI

value

range:

1~100

90 MOD

CELLRACTH

D

LdcMeaAr

pThd

ARP threshold Indicates the Allocation and Retention Priority (ARP) threshold for

low Energy Efficiency Ratio (EER) services. If the ARP value of a

service is less than the value of this parameter, the service will not be

released for congestion control.

In this version, this parameter still supports setting synchronizationbetween the M2000 and the eNodeB, but is no longer used internally.

Avoid using this parameter as it will be removed from later versions

GUI

value

range:

1~100

10 MOD

CELLRACTH

D

Key Parameters (7)


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Key Parameters (7)


ded Value

MML

CongRelO

ffset

Offset for

service

congestrelieving

Indicates the congestion release offset. The service of a specific QCI

exits the congestion state if the satisfaction rate of the service

exceeds the sum of this congestion release offset and the congestionthreshold for the QCI. The service retains the congestion state if the

satisfaction rate is below the sum of this congestion release offset

and the congestion threshold for the QCI.

GUI

value

range:1~100

20 MOD

CELLRACTHD

Preemptio

nArpThd

Preemption

ARP

threshold

Indicates the Allocation and Retention Priority (ARP) threshold for

preemption. The services that have ARP values larger than or equal

to the value of this parameter are preemptible.

In this version, this parameter still supports setting synchronization

between the M2000 and the eNodeB, but is no longer used internally.

Avoid using this parameter as it will be removed from later versions.

GUI

value

range:

1~15

5 MOD

CELLRACTHD

UlRbHigh

Thd

Uplink RB

used ratio

high

threshold

Indicates the threshold for deciding on whether the UL RB usage is

high. This threshold applies to UL admission decision. If the UL RB

usage reported by the MAC layer is above this threshold, the UL RB

usage is assumed to be high.

GUI

value

range:

1~100

95 MOD

CELLRACTHD

DlRbHigh

Thd

Downlink RB

used ratio

high

threshold

IIndicates the threshold for deciding on whether the DL resource

block (RB) usage is high. This threshold applies to DL admission

decision. If the usage of the DL RB reported by the MAC layer is

above this threshold, the DL RB usage is assumed to be high.

GUI

value

range:

1~100

95 MOD

CELLRACTHD

MaxNonG

brBearerN

um

Non-GBR

max bearer

number

Indicates the maximum number of non-GBR services (excluding IP

Multimedia Subsystem [IMS] services) that can be provided by a cell.

The value of this parameter is applied to both UL and DL.

GUI

value

range:

0~9000

OD

CELLRACTHD


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Al ith R l ti hi


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AC depends on load monitor and congestion control, and it also relates with other physical

resource assignment such as PUCCH resource assignment and downlink power assignment

and transport resource management and hardware resource assignment.

Congestion control is related with load monitor.

Page 27


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Content

Admission Control Overload Control


Algorithm Relationship Application Scenario


A li ti S i


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AC and congestion control application includes non-sharing and sharing.

In non-ran sharing scenario:

When cell load is high and PRB usage is high, it will execute AC for new RRC setup request.

Otherwise, it is to close the switcher in default. For HO service, it will always execute AC.

In ran sharing scenario:

It will always open AC and congestion control algorithm switch. Every operator will set individual AC

Threshold and execute the AC algorithm and congestion control.


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Content

Admission Control Overload Control


Algorithm Relationship Application Scenario




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HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential


Counter name Counter Description

RRC Connection Setup

Measurement

An RRC connection is a Uu interface connection for carrying user signaling messages. The setup success

rate of the RRC connection in a cell directly represents the capability of the cell to provide RRC connection

setups for users. The RRC.Setup.Cell measurement unit measures the number of RRC connection setup

requests, number of RRC connection setup attempts, and number of successful RRC connection setups in a

cell. The setup success rate of the RRC connection can be calculated on the basis of the reported counters.

Number of RRC connection

reestablishment requests

The counters measure the number of RRC connection reestablishment requests for different causes in a cell.

The RRC Connection Reestablishment Request message is an RRC signaling message sent by the UE. The

message is used to recover the RRC signaling connection.

E-RAB Setup Measurement An E-RAB is the access layer bearer for carrying service data of users. The E-RAB setup success rate in a

cell directly represents the capability of the cell to provide E-RAB connection setups for users. The E-

RAB.Est.Cell measurement unit measures the number of E-RAB setup attempts and the number of

successful E-RAB setups for each service with a different QoS Class Identifier (QCI) in a cell. The number of

E-RABs is used as the unit. The setup of one E-RAB is measured as one time.

E-RAB Release

Measurement (Cell)

An E-RAB is the access layer bearer for carrying service data of users. The E-RAB release is a process of

releasing the access layer bearer resources of users. It represents the capability of a cell to release access

layer bearer resources for users. The E-RAB.Rel.Cell measurement unit measures the number of normal E-

RAB releases and the number of abnormal E-RAB releases for each service with a different QCI in a cell.

The number of E-RABs is used as the unit. The release of one E-RAB is measured as one time.


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Thank You

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spd huawei eran3.0 admission and congestion control feature introduction 20120529 a 1.0

Documents