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

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

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

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

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

My Proposal: 1. Gather existing approaches to connectivity frameworks in ubiquitous computing environments 2. Compare them empirically 3. Extract and formally describe important concepts and features 4. Propose ideal frameworks and formally explain any relevant design decisions Adam Raby, CMSC 691b

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“ Adam Raby, CMSC 691b Kay Römer, Thomas Schoch, Friedemann Mattern, and Thomas Dbendor- fer. Smart identi¯cation frameworks for ubiquitous computing applications, 2003.

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

My Proposal: 1. Gather existing approaches to connectivity frameworks in ubiquitous computing environments 2. Compare them empirically 3. Extract and formally describe important concepts and features 4. Propose ideal frameworks and formally explain any relevant design decisions Adam Raby, CMSC 691b

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

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? Adam Raby, CMSC 691b Roy Want, Kenneth P. Fishkin, Anuj Gujar, and Beverly L. Harrison. “Bridging physical and virtual worlds with electronic tags,” In CHI, pages , 1999.

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 Adam Raby, CMSC 691b Tim Kindberg and John Barton. A web-based nomadic computing sys- tem. Computer Networks (Amsterdam, Netherlands: 1999), 35(4): , 2001.

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 Adam Raby, CMSC 691b Tim Kindberg and John Barton. A web-based nomadic computing sys- tem. Computer Networks (Amsterdam, Netherlands: 1999), 35(4): , 2001.

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 Adam Raby, CMSC 691b 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

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 Adam Raby, CMSC 691b 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

“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 Adam Raby, CMSC 691b 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.

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

My Proposal: 1. Gather existing approaches to connectivity frameworks in ubiquitous computing environments 2. Compare them empirically 3. Extract and formally describe important concepts and features 4. Propose ideal frameworks and formally explain any relevant design decisions Adam Raby, CMSC 691b

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

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

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

Adam Raby, CMSC 691b

My Proposal: 1. Gather existing approaches to connectivity frameworks in ubiquitous computing environments 2. Compare them empirically 3. Extract and formally describe important concepts and features 4. Propose ideal frameworks and formally explain any relevant design decisions Adam Raby, CMSC 691b

I Expect to Find: 1. High dependency on individual users’ capabilities 2. Major performance characteristics of various frameworks (Existing, Cellular, P2P, etc.) 3. Bottlenecks can be optimized using DNS- style name resolution caching 4. A large potential for P2P-based optimizations This may introduce security and coherence issues Adam Raby, CMSC 691b

Questions? Thanks Adam Raby, CMSC 691b