UbiConn: Providing a Ubiquitous Connectivity Experience

1. UbiConn: Providing a Ubiquitous Connectivity Experience Katherine Everitt T. Scott Saponas Susumu Harada December 6, 2004

2. Motivation • Who DOESN’T use a wireless device? • Proliferation of devices • Proliferation of services • Desire to be connected all the time wherever you are

3. Current Network Technologies • Wired (1 Gbps) • Wi-Fi (802.11a/b/g) (54 Mbps) • UMTS (300 Kbps) • EDGE (100 Kbps) GSM • GPRS (40 Kbps) }

4. What’s on the way… • Wi-Max (802.16) (75 Mbps) • Targeted towards providing last mile broadband access to businesses and residences • 3~5 mile radius • Mobile version (802.16e) not planned until 2006 • HSDPA (1 Mbps) • UMTS enhancement • Still being formalized

5. All Networks are not Created Equal • Wired: Very fast, not mobile, point coverage • Wi-Fi: Fast, mobile, limited coverage • GSM: Slow, mobile, extended coverage • Combining Wi-Fi and GSM connectivity provides “best” available service • Large coverage area • Access to high bandwidth whenever available

6. Do any of these technologies provide ubiquitous connectivity? • Operating System attempts to connect to highest bandwidth connection available • Interruptions in connectivity • Only allows one connection to be active at a time • Some applications need a constant connection at slow speed (GPRS) • Other applications want fastest connection available (Wi-Fi) • There will still be areas that have no wireless network coverage

7. Does ubiquitous connectivity exist? • One might argue the “Savvy User” has an approximation of ubiquitous connectivity • Savvy Users • Utilize resources like the hard disk to support impoverished wireless resource • Practice manual caching • Switch to wireless technology providing right class of service

8. Can we bring the experience of the savvy user to the average user? • Simultaneously combine wireless technologies • When multiple connectivity options exist, give each application the most appropriate service • IM/Terminal might utilize constant GPRS connection • Web browser would use largest bandwidth available • Proactive caching for coverage gaps • Cache frequently accessed content • Utilize large bandwidth hotspots to refresh frequently updated content

9. System Architecture • Combining Wireless Technologies • Local HTTP Proxy • MultiAdapter (Windows 1:2 Mux Network Adapter) • Proactive Caching • Local HTTP Proxy • Content Classifier • Caching System

10. Evaluation • Preliminary Evaluation of Caching System • Scenario: CSE (WiFi) -> Eng Lib 1(None) -> Eng Lib 3 (GPRS) -> CSE • Compared control to caching system • caching system works as predicted • cellular networks had high variability • MultiAdapter • Pending…

11. Future Work • More sophisticated matching of applications to available types of network connections • Availability vs Bandwidth • Explore use of cache for slow connections • For infrequently changed content • Tradeoff between freshness and speed.

12. Related Work • Heterogeneous Networks • BARWAN • CHOICE Network • Coda • Rover • Caching • Web Browser Caching • Long Term Prefetching • Edge Caching • Client Side Caching / Predictive Caching • Multiple Simultaneous Links • Load Balancing Failover (LBFO) • SpeedBooster & Multi-Channel Wireless • Mobile IP

13. Conclusion • Mobile information access is important • Used available resources to provide “savvy user” experience • Simultaneous connections • Proactive caching for coverage gaps

14. Thank you! UbiConn: Providing a Ubiquitous Connectivity Experience Katherine Everitt T. Scott Saponas Susumu Harada