An Analysis of Ubiquitous Computing Communication Frameworks for RFID-type Applications

1. An Analysis of Ubiquitous Computing Communication Frameworks for RFID-type Applications Adam Raby CMSC 691b

2. Outline • Motivation & Background • My Proposal • Related Work • Result Expectations • Future Work • Conclusions Adam Raby, CMSC 691b

3. Ubiquitous Computing is the Integration of Computing into all aspects of every-day life • First defined by Mark Weiser (1991) • Think of the ubiquity of written languages • Requires • Mobility • Pervasiveness • Transparency • Consider Weiser's example of the relative disappearance of electric motors • We can’t assume that our currently technologies and architectures are optimal Adam Raby, CMSC 691b

4. Ubiquitous Computing Technologies are Everywhere! • Consider RFID • With high levels of integration of RFID-like technology into everyday life, there needs to be a sound communication framework Adam Raby, CMSC 691b

5. This analysis has to be done before Ubiquitous Computing can become a reality • Miniaturization • Decreasing Power Requirements • Increasing Wireless Connectivity • Increasing Pervasiveness = A Need for a Well-Defined and Empirically Evaluated Connectivity Framework Adam Raby, CMSC 691b

6. My Proposal: • Gather existing approaches to connectivity frameworks in ubiquitous computing environments • Compare them empirically • Extract and formally describe important concepts and features • Propose ideal frameworks and formally explain any relevant design decisions Adam Raby, CMSC 691b

7. Related Work • Römer (2003) • Investigated the development of a framework for a "smart" approach to identifying RFID-tagged objects in a Ubiquitous Computing environment • “Smart" behavior = a computing environment's ability to pair objects with their functions, anticipate events, and monitor object locations • "Smart Toolbox“ Kay Römer, Thomas Schoch, Friedemann Mattern, and Thomas Dbendor- fer. Smart identi¯cation frameworks for ubiquitous computing applications, 2003. Adam Raby, CMSC 691b

8. Römer: The Framework Matters • Two Approaches • Jini – Distributed Java Objects (Winner) • Web Services • Neither did well under heavy-loads Kay Römer, Thomas Schoch, Friedemann Mattern, and Thomas Dbendor- fer. Smart identi¯cation frameworks for ubiquitous computing applications, 2003. Adam Raby, CMSC 691b

9. My Proposal: • Gather existing approaches to connectivity frameworks in ubiquitous computing environments • Compare them empirically • Extract and formally describe important concepts and features • Propose ideal frameworks and formally explain any relevant design decisions Adam Raby, CMSC 691b

10. Many Models Use RFID Technology to Bridge the Real and Virtual Worlds • Radio Frequency Identifier (RFID) • Small, versatile transponders capable of storing a small fixed number of bits • There are several different types • Each type has unique range, power consumption, and transmission characteristics • The most common forms of these tags are inexpensive, reliable, and passive • They provide a standardized medium Adam Raby, CMSC 691b

11. RFID Solves Several Problems Facing the Achievement of Ubiquitous Computing • Often, attempts to connect the real and virtual world through specialized input devices and gadgets are expensive and too application-specific (Want, 99) • Properly distributing the burden of complexity is a key issue in ubiquitous computing (Want, 99) • Is it really necessary for a light to know when someone has entered the room, or is it enough for something else to know that there is a light and a person in the room? Roy Want, Kenneth P. Fishkin, Anuj Gujar, and Beverly L. Harrison. “Bridging physical and virtual worlds with electronic tags,” In CHI, pages 370-377, 1999. Adam Raby, CMSC 691b

12. Cooltown • Designed upon three principles • Ubiquitous access • Users are able to access outside resources, like the internet, from virtually any device, using common protocols • Just enough middleware • Much less platform and capability dependent • Locality • the technology's ability to be aware of its environment and act accordingly • Uses handheld devices, infrared beacons, barcodes, and RFID tags to situate its users • The infrared beacons, barcodes, and RFID tags resolve to URLs for webservers which provide contextual information about the users environment • A large wired infrastructure supports the CoolTown system, managing information about all the "tagged" people, places, and things Tim Kindberg and John Barton. A web-based nomadic computing sys- tem. Computer Networks (Amsterdam, Netherlands: 1999), 35(4):443-456, 2001. Adam Raby, CMSC 691b

13. Cooltown • CoolTown's researchers rely on several different technologies to combat some of the shortcomings of RFID, primarily range • Demonstrates the need for support of Heterogeneity in Ubiquitous Computing Frameworks Tim Kindberg and John Barton. A web-based nomadic computing sys- tem. Computer Networks (Amsterdam, Netherlands: 1999), 35(4):443-456, 2001. Adam Raby, CMSC 691b

14. Hähnel And Colleagues Developed An Approach To Mapping And Localization Using RFID • A RFID sensor-equipped robot is able to navigate and map environments using a laser sensor and a RFID sensor D. Hähnel, W. Burgard, D. Fox, K. Fishkin, and M. Philipose. “Mapping and localization with RFID technology.” In Proc. of the IEEE International Conference on Robotics and Automation (ICRA), 2004 Adam Raby, CMSC 691b

15. Hähnel’s Work Demonstrated Several Important Aspects of RFID-Type Systems • They often require secondary systems (e.g. lasers) • They’re highly susceptible to instrumentation • They require a lot of the receiver • Are we already leaning towards a system with a heavily loaded client? • And again, demonstrates the need for Heterogeneity in Ubiquitous Computing Frameworks D. Hähnel, W. Burgard, D. Fox, K. Fishkin, and M. Philipose. “Mapping and localization with RFID technology.” In Proc. of the IEEE International Conference on Robotics and Automation (ICRA), 2004 Adam Raby, CMSC 691b

16. “Websigns” is an Example of a Completely Virtual System • GPS data is used to situate a user in their environment • Once the Websigns system determines a users location, it returns any relevant contextual information to the user based on the Websigns in their vicinity • Users are expected to have constant access to GPS data as well as internet access • A central site for maintaining Websigns also introduces a central point of failure and difficulties in scalability • In a system that uses actual RFID tags, offline users would be able to cache data for later resolution • Real tags provide another level of user interaction and control Salil Pradhan, Cyril Brignone, Jun-Hong Cui, Alan McReynolds, and Mark T. Smith. “Websigns: Hyperlinking physical locations to the Web,” Computer, 34(8):42-48, 2001. Adam Raby, CMSC 691b

17. There’s A Lot to Learn Just By Gathering Current Frameworks What Next? Adam Raby, CMSC 691b

18. My Proposal: • Gather existing approaches to connectivity frameworks in ubiquitous computing environments • Compare them empirically • Extract and formally describe important concepts and features • Propose ideal frameworks and formally explain any relevant design decisions Adam Raby, CMSC 691b

19. These Systems Can Be Analyzed Using Network Analysis Tools Virtual Inter-Network Testbed (VINT) Adam Raby, CMSC 691b

20. Model Ubiquitous Frameworks as Computer Networks Cooltown: Internet Web Service Tagged Artifact Internet Tagged Artifact User User User Tagged Artifact Adam Raby, CMSC 691b

21. This Approach Provides Several Common Methods of Evaluation • Metrics • Throughput • Latency • Message Complexity • Error Rates • Bottlenecks • Behavior Under the Atypical Loads of a Ubiquitous Computing Environment Adam Raby, CMSC 691b

22. Behavior Under the Atypical Loads of a Ubiquitous Computing Environment Adam Raby, CMSC 691b

23. My Proposal: • Gather existing approaches to connectivity frameworks in ubiquitous computing environments • Compare them empirically • Extract and formally describe important concepts and features • Propose ideal frameworks and formally explain any relevant design decisions Adam Raby, CMSC 691b

24. I Expect to Find: • High dependency on individual users’ capabilities • Major performance characteristics of various frameworks (Existing, Cellular, P2P, etc.) • Bottlenecks can be optimized using DNS-style name resolution caching • A large potential for P2P-based optimizations • This may introduce security and coherence issues Adam Raby, CMSC 691b

25. Questions? Thanks Adam Raby, CMSC 691b