3G and WLAN Interworking for Fixed-Mobile Convergence

Transcription

1 3G and WLAN Interworking for Fixed-Mobile Convergence Presentation for the CDG Technology Forum on Inter-Technology Networking April 30, 2008, San Francisco Presenter: Rolf de Vegt, 1

2 Agenda 1. Context and Introduction 2. Trends and Drivers for 3G/WLAN Interworking 3. Highlights of 3G-WLAN Inter-working Standards and System Architecture 4. Benefits of using n for WLAN Inter-working 5. Features and Enhancements for Improved 3G WLAN Interworking 6. Technology Trial Results 7. Conclusions 2

3 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 n 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. 3

4 2. Trends and Drivers for 3G/WLAN Interworking 4

5 3G/WLAN Interworking for Converged IP Services Operator Controlled 3G/WLAN Offering Same Data and Voice Services Across Systems Same Authentication/Authorization Additional Revenue Opportunity Improved WLAN AP Configurations Benefits to Customers System Selection Transparent to the User Seamless Inter-System Handoff Single Mobile Number Operator Services 3G WLAN Operator Client 5

6 End User Trends US Wireless Voice Minutes Usage 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 in North America by 2007 (igr, 03/07) Other 26% Car 40% Work 10% Home 24% Source: Yankee Group, 2005 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 Embedded Wireless Notebooks 6

7 Drivers for Wireless Operators Wireless operators entering traditionally fixed domains 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 Residential flat rate Homezone plan Per minute billing standard plan WLAN hotspots extends Homezone coverage 7

8 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 plan provides limited mobility Standard MNO provided mobility services WLAN hotspots extends VoIP coverage 8

9 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. 9

10 3. Highlights of 3G-WLAN Standards and System Architecture 10

11 Standards Support 3G/WLAN Interworking IMS Rel-5 and Rel-6 published Rel-7 frozen in Dec 06 Rel-8 expected to be frozen in 4Q 08 VCC: WiFi VoIP CS TS (Stage-2) and TS (Stage-3) as part of Rel-7 MMD Rev-0 and Rev-A published Rev-B will be published Dec 07 VCC: X.P0042 (Stage-2 and 3) HRPD VoIP 1X-CS WiFi VoIP 1X-CS Published by Oct 07 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 11

12 3G/WLAN Interworking for Packet Data Services Allows 3G subscribers to use WLAN to access an operator s 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.S ) 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 AAA PDG/PDIF 3G Packet Data Service (including Internet) WLAN Access Network Internet 12

13 3G-WLAN Voice Interworking Architecture (3GPP2) BTS Abis BSC Cellular Domain A IS-41 MSC C VLR HLR/AC MMD/IMS core network: CSCF: SIP server HSS for authentication Media Gateway: MGW MGCF Dual mode handset: Dual RF chains IMS client software VCC AS IS-41 PSTN ISC HSS WLAN Access IMS Domain CSCF MGCF AP PDIF Internet MGW WLAN AP: Air link authentication Optimized configurations VCC AS: Manages mobile reachability info Selects access for mobile terminated sessions (UE selects access for mobile originated sessions) Anchors all IMS sessions 13

14 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 VLR ISUP BSC MSC BTS HLR/AC VCC AS HSS SIP CSCF MGCF PDIF MGW 14

15 3G-WLAN Voice Interworking Architecture (3GPP) VCC AS: Manages mobile reachability info Selects access for mobile terminated sessions (UE selects access for mobile originated sessions) Anchors all IMS sessions B VLR Iub RNC Iu-cs MSC Node-B MAP C HLR/AC ISUP Dual mode handset: Dual RF chains IMS client software VCC AS MAP PSTN IMS Domain ISC SH HSS WLAN Access SH CSCF SIP MGCF MEGACO ISUP AP PDG Internet MGW PDG: provides VPN entry into carrier Intranet 15

16 4. Benefits of Using n for WLAN Interworking 16

17 Introduction to n Latest generation of Wi-Fi Technology Wi-Fi Alliance started certifying interoperability of devices based on Draft 2.0 of the upcoming n standard in June 2006 Certification of Approved n based devices scheduled to start in July 2009 Key Enhancements to Legacy Wi-Fi in n 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 17

18 Key Advantages of n Home 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 voice calls, video games and other multimedia applications Back up large files in a snap Enterprise and Hot Spot 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 a/b/g clients to connect Reduced CapEx and OpEx for Hot Spot providers, due to larger coverage areas of APs 18

19 802.11n Access Points with Legacy Wi-Fi Radios in Mobile Devices 11n AP Legacy Client Most WLAN enabled Mobile Devices currently shipping with a, b or g Even without n 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 19

20 Benefits of Having n on Both Sides of the Link Range Extension for a Single Data Stream due to Support of Space Time 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 n deployments can segregate voice on 5 GHz 20

21 5. Features and Enhancements for Improved 3G WLAN Interworking 21

22 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 22

23 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 Network Deployments and Usage Scenarios 3G / WLAN handoffs with varying loading WLAN to WLAN handoffs in enterprise settings Mobile-Centric Algorithm Can Meet all the Requirements Without Network Changes WLAN 3G Network 23

24 Multiple, Intelligent Triggers for Robust Handoff Operation Signal Strength Based Handoff Alone Does Not Provide Adequate 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, and Application Layer Triggers for Greater Reliability 1. Signal strength (RSSI) 2. Uplink MAC frame failures and retransmissions 3. Downlink VoIP frame losses 4. Backhaul QoS degradation (PQMF) 3G Network APP: Path Quality Monitoring Function VCC AS MAC: Uplink Metrics PHY: RSSI Internet PDG/PDIF PQMF Server MGW APP: VoIP Frame Loss 24

25 Reliability Improvement Through Application Layer Monitoring Path Quality Monitoring Function (PQMF) Measures Path Quality Between Device and Operator s 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 3G Network Path Quality Monitoring Function VCC AS Internet PDG/PDIF PQMF Server MGW 25

26 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 time by intelligent WiFi scans and longer sleep periods Example: a standby time of 4 days is claimed for T- Mobile Hotspot@Home phones 26

27 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 e (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 27

28 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 28

29 6. 3G/WLAN Interworking Technology Trial Results 29

30 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 fine-tune algorithms and parameter Settings Carrier-grade VoWLAN with imperceptible handoffs between 3G and WLAN 30

31 Field Trial Architecture 31

32 6. Conclusion 32

33 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 MSM WLAN 33

34 Conclusion Qualcomm is leveraging its expertise in 3G and technologies to provide a leading 3G/WLAN Interworking solution n 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 34