An Analysis of Ubiquitous Computing Communication Frameworks for RFIDtype Applications

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

• Motivation Background
• My Proposal
• Related Work
• Result Expectations
• Future Work
• Conclusions

Adam Raby, CMSC 691b
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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 cant assume that our currently technologies
  and architectures are optimal

Adam Raby, CMSC 691b
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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
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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
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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
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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 identication
frameworks for ubiquitous computing
applications, 2003.
Adam Raby, CMSC 691b
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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 identication
frameworks for ubiquitous computing
applications, 2003.
Adam Raby, CMSC 691b
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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
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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
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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
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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
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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
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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
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Hähnels Work Demonstrated Several Important
Aspects of RFID-Type Systems

• They often require secondary systems (e.g.
  lasers)
• Theyre 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
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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
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Theres A Lot to Learn Just By Gathering Current
Frameworks

• What Next?

Adam Raby, CMSC 691b
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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
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These Systems Can Be Analyzed Using Network
Analysis Tools

• Virtual Inter-Network Testbed (VINT)

Adam Raby, CMSC 691b
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Model Ubiquitous Frameworks as Computer Networks

• Cooltown

Internet
Web Service
Tagged Artifact
Internet
Tagged Artifact
User
User
User
Tagged Artifact
Adam Raby, CMSC 691b
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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
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Behavior Under the Atypical Loads of a Ubiquitous
Computing Environment
Adam Raby, CMSC 691b
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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
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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
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Questions?

• Thanks

Adam Raby, CMSC 691b