3G & WLAN Interworking

8/12/2019 3G & WLAN Interworking

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1Qualcomm, Inc.

3G and WLAN Interworking for

FixedFixed--Mobile ConvergenceMobile Convergence

Presentation for the CDG Technology

Forum on Inter-Technology Networking

April 30, 2008, San Francisco

Presenter: Rolf de Vegt, [email protected]


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2Qualcomm, Inc.

Agenda

1. Context and Introduction

2. Trends and Drivers for 3G/WLAN Interworking

3. Highlights of 3G-WLAN Inter-working Standards and SystemArchitecture

4. Benefits of using 802.11n for WLAN Inter-working

5. Features and Enhancements for Improved 3G WLAN Inter-working

6. Technology Trial Results

7. Conclusions


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3Qualcomm, Inc.

1. Context and Introduction

The theme of the conference is Inter-Technology Networking

The purpose of this presentation:

Outline the trends and drivers leading to increased adoption of WLAN

Cellular Interworking

Provide an overview of relevant standards and system architectures

Highlight the benefits of using 802.11n technology

Inform you about key enhancements QC identified for 3G WLAN

Interworking

Share the results of a Field Trial of Qualcomm 3G WLAN Interworking

enhancements.


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4Qualcomm, Inc.

2. Trends and Drivers for 3G/WLAN

Interworking


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3G/WLAN Interworking for Converged IP Services

Operator Control led

3G/WLAN Offering

3G3G WLANWLAN

OperatorOperator

ServicesServices

OperatorOperator

ClientClient

System Selection Transparent to the UserSystem Selection Transparent to the User

Seamless InterSeamless Inter--System HandoffSystem Handoff

Single Mobile NumberSingle Mobile Number

Benefits to Customers

Same Data and Voice Services Across Systems

Same Authentication/Author ization

Additional Revenue Opportunity

Improved WLAN AP Configurations


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End User Trends

A third of wireless voice minutes are used

either at home or at work

Fixed-mobile substitution is a reality Over 13 million landline phones replaced inNorth America by 2007 (iGR, 03/07)

Increasing adoption of VoIP

Portable phones and softphones can be

used anywhere with an IP connection

Increasing usage of wireless data

Fast growth of 3G data services

Need for converged 3G/WLAN data services

Work

10%

Home

24%

Car

40%

Other

26%

Source: Yankee Group, 2005

Embedded WirelessNotebooks

US Wireless Voice Minutes Usage


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Drivers for Wireless Operators

Coverage In-building coverage extension

High data rates in poor 3G coverage areas

Reduce Churn Increase stickiness through custom plans

Enhance corporate plans (e.g. wireless PBX)

Cost Reduction Minimizes transport costs

Delay network investment to improve capacity

New Services and Revenues Bundled services Accelerate wireline substitution

Rich services in poor 3G coverage areas

Wireless operators entering traditionally fixed domains

Residential flat rate Homezone plan

Per minute billing

standard plan

WLAN hotspots

extends

Homezone

coverage


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Drivers for Wireline Operators

Wireline and MVNOs operators expanding services beyond the home

Through partnerships, operators can offer mobile services

Reduce Churn

Strengthen product portfolio and brand Single bill for all services

Cost Reduction Reduce MoU on partner network Use own transport network (DSL, Cable)

New Services and Revenues

Become main communications provider Recapture lost users and minutes to wireline substitution

Residential

VoIP planprovides

limited

mobility

Standard MNO

provided mobility

services WLAN

hotspots

extends

VoIP

coverage


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Cellular/VoWLAN Dual-mode Handsets

A Growing Number of Cellular/VoWLAN dual-mode handsets available DoCoMo launched Passage Duple service (WCDMA/VoWLAN) at end of 2004

Orange Unik launched in Oct 06

T-mobile HotSpot@Home launched in June 2007

Other service launches include BT, Telecom Italia, Telia Sonera, etc.


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3. Highlights of 3G-WLAN Standards

and System Architecture


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Standards Support 3G/WLAN Interworking

MMD Rev-0 and Rev-A published Rev-B will be published Dec07

VCC: X.P0042 (Stage-2 and 3) HRPD VoIP 1X-CS

WiFi VoIP 1X-CS

Published by Oct 07

IMS Rel-5 and Rel-6 published

Rel-7 frozen in Dec06

Rel-8 expected to be frozen in 4Q08

VCC: WiFi VoIP CS TS 23.206 (Stage-2) and TS 24.206

(Stage-3) as part of Rel-7

UMA GAN Access to A/Gb Intf (Rel 6/7) Published

Access to Iu Intf (Rel-8) In Progress

Approved: 11a/b/g: power saving optimizations

11e: QoS and talk time improvement

11r: Inter-AP handoffs

In progress: 11n: Increased throughput and range

11u: WLAN / Cellular interworking 11v: Further standby time improvement


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3G/WLAN Interworking for Packet Data Services

Allows 3G subscribers to use WLAN to access an operators packet

data services E.g., rich multimedia to mobile phones and connectivity for laptops at hotspots

Standardized in 3GPP (I-WLAN TS23.234) and 3GPP2 (X.S0028-200) Authentication and security provided by PDIF and existing AAA Multimedia Session Continuity (MMSC) to support seamless handoff being defined

in 3GPP (Rel-8) and 3GPP2

WLAN

Access

Network

PDG/PDIFPDG/PDIF

Internet

3G Packet Data

Service (including

Internet)

AAAAAA


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BSCBSC MSCMSC

Cellular Domain

Abis A

C

WLAN Access CSCFCSCF

VCC ASVCC AS

MGCFMGCF

MGWMGW

IMS Domain

IS-41

ISC

IS-41

AP

BTS

VLR

HLR/AC

HSS

PDIFPDIF

Internet

PSTN

3G-WLAN Voice Interworking Architecture (3GPP2)

WLAN AP:Air link authenticat ion

Optimized configurations

Dual mode handset:

Dual RF chains

IMS client software

MMD/IMS core network :

CSCF: SIP server

HSS for authentication

Media Gateway: MGWMGCF

VCC AS: Manages mobile reachabili ty info Selects access for mobile terminated sessions

(UE selects access for mobile orig inated sessions)

Anchors al l IMS sessions


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Voice Call Continuity: WLAN-3G Handoff

Mobile decides to handoff from WLAN to 3G

Establish CS call and send signaling to VCC-AS

CS voice connection established to MGW

Tear down WLAN VoIP connection

BSCBSC MSCMSC

CSCFCSCF

VCC ASVCC AS

MGCFMGCF

MGWMGW

BTS

VLR

HLR/AC

HSS

PDIFPDIF

ISUP

SIP


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15Qualcomm, Inc.

3G-WLAN Voice Interworking Architecture (3GPP)

RNCRNC MSCMSCIub Iu-cs

C

B

ISUP

ISUP

WLAN Access CSCFCSCF

VCC ASVCC AS

MGCFMGCF

MGWMGW

IMS Domain

MAP

ISC

SH

SH

MEGACO

SIP

MAP

AP

Node-B

VLR

HLR/AC

HSS

PDGPDG

Internet

PSTN

VCC AS: Manages mobile reachability info Selects access for mobile terminated sessions

(UE selects access for mobile originated sessions) Anchors al l IMS sessions

PDG: provides VPN entry into carrier Intranet

Dual mode handset:

Dual RF chains

IMS client so ftware


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4. Benefits of Using 802.11n for

WLAN Interworking


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Introduction to 802.11n

Latest generation of Wi-Fi Technology

Wi-Fi All iance started certifying interoperability of devices based on

Draft 2.0 of the upcoming 802.11n standard in June 2006

Certi fication of Approved 802.11n based devices scheduled to startin July 2009

Key Enhancements to Legacy Wi-Fi in 802.11n standard:

Increased Throughput and Range due to the use of MIMO WFA draft 2.0 testing, tests for 2 Spatial Streams, Standard specifies up to 4

spatial streams, with a max link rate of 600 Mbps

Increased Throughput due to the use of Frame Aggregation

Techniques and/or the use of 40MHz channels

Up to 5X the Throughput and 2X the Range compared to Legacy Gear


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Key Advantages of 802.11n

Enterprise and Hot SpotHome Environment

Whole Home Coverage; a

strong Wi-Fi signal that can

blanket the entire home

A whole family sharing an

internet connection on a wide

array of devices without

degradation

Moving HD video and audio

streams effortlessly from device

to devices, throughout the home

Best user experience with voicecalls, video games and other

multimedia applications

Back up large files in a snap

Plenty of bandwidth to support

data-intensive applications (e.g.

video) and more users

Reach hard-to-cover spots like

stairwells, corridors, and exterior

areas with ease

Support more users on a more

efficient WLAN infrastructure

Ability for legacy 802.11a/b/g

clients to connect

Reduced CapEx and OpEx for

Hot Spot providers, due to larger

coverage areas of APs


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802.11n Access Points with Legacy Wi-Fi Radios

in Mobile Devices

11n AP Legacy Client

Most WLAN enabled Mobile

Devices currently shipping with

802.11a, b or g

Even without 802.11n Radios on

the client side, notable Range and

Power Consumption Benefits:

Increased Receive Sensitivity

at Access Points

Transmit Diversity at Access

Point

Higher Data Rates Enabled at

any given point

Lower Output Power required

of Client


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20Qualcomm, Inc.

Benefits of Having 802.11n on Both Sides of the Link

Range Extension for a Single Data Stream due to Support of SpaceTime Block Coding (STBC)

Higher Throughput and Extended Range for Mobile Devices with

Multiple Antennas (1x2 and 2x2 implementations)

Higher Peak data-rates with Spatial Multiplexing: 2 Spatial Streams: 130 Mbps

1 Spatial Stream: 65 Mbps

Legacy a/g: 54 Mbps

Higher Throughputs for transfer of large files (Music, Video,Pictures) due to Aggregation Techniques (A-MPDU orA-MSDU)

Range Extension Due to the use of the Legacy Duplicate Mode

Power Safe Features Increased Overall Network Capacity

11n will Spur Migration to the 5 GHz band 5GHz is cleaner spectrum; fewer risks for interference

New 802.11n deployments can segregate voice on 5 GHz


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5. Features and Enhancements for

Improved 3G WLAN Interworking


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3G WLAN Interworking Considerations

Robust Handoffs between Networks

Triggers and algorithms for efficient handoff

End-to-end call quality management

Efficient Power Management

Improving WLAN standby and talk time

Voice over WLAN Performance QoS Management over WiFi

Interference in unlicensed spectrum

System Search and Selection


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Mobile-Based Algorithms Enables Seamless

Inter-system Handoff

Robust and Efficient Handoff Algorithms achieve Make-before-break handoff with no call drop Maximize WLAN range while maintaining voice quality Minimize packet losses during handoff Stable handoff avoiding unnecessary ping-pong

Handoff Algorithms Also Need to Handle Diverse NetworkDeployments and Usage Scenarios 3G / WLAN handoffs with varying loading WLAN to WLAN handoffs in enterprise settings

Mobile-Centric Algorithm Can Meet all the Requirements WithoutNetwork Changes

3G NetworkWLAN


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Multiple, Intelligent Triggers for Robust Handoff Operation

Signal Strength Based Handoff Alone Does Not ProvideAdequate Performance RSSI measurement is noisy near handoff boundary Does not detect interference for WLAN connection Cannot monitor uplink quality

Does not detect backhaul failures

Improved Handoff Algorithm Combines PHY, MAC, andApplication Layer Triggers for Greater Reliability1. Signal strength (RSSI)2. Uplink MAC frame failures and retransmissions3. Downlink VoIP frame losses4. Backhaul QoS degradation (PQMF)

Internet

VCC ASVCC AS

MGWMGWPDG/PDIF

PQMF Server

PDG/PDIF

PQMF Server

3G Network

MAC: Uplink Metrics

PHY: RSSI

APP: VoIP Frame Loss

APP: Path Quality Moni toring Funct ion


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Reliability Improvement Through Application Layer

Monitoring

Path Quality Monitoring Function (PQMF) Measures Path Quality Between

Device and Operators Network

Secure, adaptive, ping-type procedure with low overhead

Server function provided by PDG/PDIF

With PQMF, Mobile Devices Can More Accurately Decide When to HO

Prevent initiate call on an overloaded WLAN system

Respond to WLAN QoS failures during call silence periods

Distinguish between local and remote link failures

Internet

PathQualityMonitoringFunction

VCC ASVCC AS

MGWMGWPDG/PDIF

PQMF Server

PDG/PDIF

PQMF Server

3G Network


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Battery Life Close to 3G Phones

Improved talk time by transitioning to sleep

during calls

Based on power save mechanisms such as U-APSD(802.11e)

Examples: talk time up to 6 hours in WiFi mode for T-

Mobile Hotspot@Home phones

Improved standby t ime by intelligent WiFiscans and longer sleep periods

Example: a standby time of 4 days is claimed for T-

Mobile Hotspot@Home phones


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27Qualcomm, Inc.

High Quality VoIP Calls in WLAN

WLAN Can Meet Requirement of Voice Quality in

Mixed Traffic

VoIP bandwidth is low compared to WLAN throughput

Explicit QoS provided for VoIP by 802.11e (WMM)

VoIP Traffic Should Be Prioritized over the

Backhaul Appropriately

May require agreements with ISPs PQMF helps to detect backhaul QoS failures and

handing over to cellular if needed

Adaptive De-Jitter Buffer Improves Voice Quality

Mitigate Effects of Variable Packet Delay


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Smart System Search and Selection

Algorithms Optimized to Find and Select New Systems in a

Fast and Efficient Manner

Minimize frequency of system scans and increase battery life

Identifying authorized, commonly used WLAN hotspots

Idle handoff between WLAN and WAN (and vice versa) Finding systems quickly enough for mobility transition

Active Scan algorithm can provide an order of magnitude

performance improvement vs. basic scanning algorithm


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6. 3G/WLAN Interworking

Technology Trial Results


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3G/WLAN Interworking Validated by

Technology Trial

Six weeks of real-world testing of handoffs between 3G and WLAN Over 700 VCC calls with over VCC 1200 handoffs

Residential settings: suburban, urban, dense apartments

Enterprise settings with full coverage, spotty coverage

Scenarios designed to test performance limits Extensive walking test

Poor cellular coverage

WLAN and backhaul loading: downloads, uploads

Interference from microwave ovens, Bluetooth, cordless phones

Extensive data collection and analysis used to f ine-tune algorithms

and parameter Settings

Carrier-grade VoWLAN with imperceptible handoffs

between 3G and WLAN


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Field Trial Architecture


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6. Conclusion


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3G/WLAN Chipset Solutions Available

Leveraging its expertise in 3G and WLAN technologies, Qualcomm

provides a leading 3G/WLAN interworking solution

Commercial chipsets and software for UMTS and CDMA

Fully tested MSM software for both 3G and WLAN

Fully integrated IMS VoIP client software IMS/MMD standards compliant

Supports IMS/CS handoff (VCC)

IOT test with infrastructure vendors

Successful IOT test with Nortel IMS and VCC-AS

Successful IOT test with other vendors

Joint development with Kineto for UMA-GAN solution

WLAN

MSM


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Conclusion

Qualcomm is leveraging its expertise in 3G and 802.11 technologies

to provide a leading 3G/WLAN Interworking solution

802.11n technology provides key advantages in range, throughput,

power consumption and network capacity

Efficient algorithms and triggers enable robust seamless handoffs

QoS and interference mitigation offer high voice quality over WLAN

Smart system search and selection to maximize battery life

IMS-based 3G/WLAN interworking is a reality that operators can

leverage to provide FMC and future services

Qualcomm provides complete 3G/WLAN solutions for terminals Chipsets and IMS client software

Extensive testing by technical trial and IOT

Documents

3G & WLAN Interworking