1. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 1 Enabling Seamless Hand-Off Across Wireless Networks Albert Young Ralink Technology, Inc Phone: 408-725-8070 x 31 e-Mail: ayoung@ralinktech.comayoung@ralinktech.com

2. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 2 Outline Introduction, Market, & Applications. Requirements Wireless LAN & Wireless WAN Progress Key Technologies Summary of Analysis

3. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 3 Introduction Integration of WPANs (e.g. Bluetooth), WLANs (802.11a/b/g) and WWANs (e.g. cellular networks) Goals for inter-working: –Seamless hand-off (no user interaction) –Robust security –Roaming agreements among carriers / operators

4. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 4 Introduction

5. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 5 Market - Mobile Internet Includes the wireless Web Also includes a rich array of value-added services that the IP network itself delivers, including variable levels of data throughput, security, quality of service, and location features.

6. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 6 Market Public Access WLAN over 3G –Lower costs for large volume of data –Higher speed –Location with pinpoint accuracy Enterprise/SMB/Home WLAN –High speed data –Voice

7. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 7 Applications 2-way VOIP, video telephony, video teleconferencing 1-way streaming audio/video 2-way interactive email/Web Non time-critical (background email/file downloads) They need the inter-working of Wireless Networks to meet various levels of requirements in mobility, security, and QoS

8. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 8 Requirements on Mobility Persistent connectivity. Roaming without losing network sessions Transparent to users Smart hand-off between WLAN & 3G Partnership or roaming agreements between WWAN operators and WLAN ISPs Protocols and methods for access control, roaming, billing and provisioning

9. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 9 Requirements on Security Protocols and methods for secure tunnelling, authentication, encryption, and integrity detection Fast re-authentication when roaming across networks Centralized management and control

10. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 10 Requirements on QoS Efficient QoS provision Offering the level of QoS that the user subscribed and being charged Supporting the mapping between IEEE 802.1p priority levels (0-7) and IP DiffServ

11. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 11 802.11 WLAN Challenges Inter Access Point Protocol (IAPP) –802.11f draft Robust Security Network –802.11i draft MAC enhancement for QoS –802.11e draft

12. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 12 WWAN - 3G Up to 2 Mbps for packet data, voice, and video Enable a new generation of applications - collaborative and multimedia services Always-on, anywhere, high-speed data communications service from their home networks via a secure Mobile IP tunnel UMTS and cdma2000. Years before compatibility barriers are lifted between competing 3G solutions

13. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 13 WWAN Challenges Fair and priority services –Ensure that bursts of Internet traffic headed to one subscriber do not affect others –Deliver higher quality (higher bandwidth or lower latency) to users that pay more Seamless mobility –Always-on mobile IP service, set-up and tear down tunnels –Managing mobility within a single network, as well as among different types of networks.

14. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 14 Inter-working Status 3GPP started a feasibility study on WLAN- UMTS inter-working ETSI BRAN GSM Association Architecture alternatives –Tight inter-working –Loose inter-working Proprietary solutions

15. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 15 Key Technologies for Enabling Seamless Hand-Off Mobile IP Fast Hand-Off AAA IPSec QoS MAC Enabler

16. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 16 Mobile IP for Inter-System mobility IP should be the “Unification layer” across the WLAN and WWAN media. Generic and few assumptions about access network Allow seamless network traversal so that mobile users could experience ubiquitous communications that are secure and spontaneous A mobile user can maintain connections and permanent IP address as he roams through different subnet

17. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 17 Mobile IP Mobile Node (MN) go through registration process with Foreign Agent (FA), AAA, and Home Agent (HA) HA does authentication and traffic management FA is the point of entry for a MN to visit different networks –MN does not need to acquire a network (IP) address on the foreign network

18. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 18 Drafts of IETF on Fast Hand-Off Various drafts on specific aspects Low Latency Handoffs for Multiple- Interfaced MNs Context Transfers Between Nodes Mobile IPv6 handoff by Explicit Multicast Protocol enhancements to minimize handoff latency to support real-time traffic

19. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 19 AAA Servers In use within the Internet today to provide accounting, authentication and authorization services for dial-up computers Valuable for mobile nodes using Mobile IP when the nodes are attempting to connect to foreign domains with AAA servers Identify clients by using the Network Access Identifier (NAI)

20. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 20 IPSec Authentication, Confidentiality and Integrity Compliant with corporate security policies – VPN End-to-End security provides best protection to corporate resources Uses IKE Phase 1 & 2 - the result is a symmetric key used for encryption and decryption of traffic Challenge is to achieve seamless hand-off with VPN

21. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 21 QoS UMTS QoS architecture –Defines QoS profiles that are negotiated between a mobile station and a SGSN –Supports four QoS classes: Streaming, Conversational, Interactive, Background WLAN 802.11e draft in progress No complete solutions

22. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 22 MAC Enabler Radio sense of the network Hand-Off triggering algorithms Better collaboration with upper layers Configuration/switching based on cost, speed etc.

23. doc.: IEEE 802.11-02/345r0 Submission May 2002 Albert Young, Ralink TechnologySlide 23 Summary of Analysis Mobile IP allows roaming across heterogeneous networks No common authentication schemes How to choose an architecture - separate AAA server or integrated with HLR? Needs automatic selection of network connection and switching of networks Real-time applications such as Voice over IP severely challenges seamless hand-off across networks