Prof. Maria Papadopouli

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COMP 290-086 Fall 2003 Mobile Networks and
Computing

• Prof. Maria Papadopouli
• maria_at_cs.unc.edu

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Class Mechanics

• Q Is a seminar just like a course ?
• NO !
• Several students presentations
• Great opportunity to find interesting research
  projects

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Seminar Information

• Web page
• http//www.cs.unc.edu/maria/courses/fall03/
• Lecture
• Tuesday Thursday 200-315pm SN325
• Email list
• mobile_at_cs.unc.edu
• Office hours
• Tue/Thu 315-400pm _at_ SN 356 (subject to change)
• Meet each group

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Textbooks

• 802.11 Wireless Networks, The definitive guide.
  Matthew S. Gast, O'Reilly, 2002, ISBN
  0-596-00183-5
• Reading material _at_ course web page
• Additional reference (not required)
• Ad Hoc Networking. Charles E. Perkins, Addison
  Wesley, 2001, ISBN 0-20130976-9
• Computer Networking A Top-Down Approach Featuring
  the Internet. James F. Kurose and Keith W. Ross,
  Addison Wesley, 2002, ISBN 0-201-477114
• Wireless Communications Principles and Practice.
  Theodore S. Rappaport, Prentice Hall (Second
  Edition), ISBN 0-13-042232-0

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Seminar Information

• Grading
• Project assignment 50
• Presentation 40 (4 paper presentations)
• Final demo/presentation 10
• Evaluation at the end of each presentation
• Mid-term evaluation of your project
• TAs contact details
• Francisco Chinchilla fchinchi_at_cs.unc.edu
• Josh Levy levy_at_cs.unc.edu

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Announcements

• Select presentation dates by September 7, 2003
• Define project by September 21, 2003
• No class on 9/16 and 10/14
• Attend SAMSI workshop on sensor networks (with
  Deborah Estrin) 9/13-15
• Presentations demos on 12/4 (subject on change)
• Available PCMCIA cards, laptops, iPaqs to borrow
• Available networking infrastructure for
  measurements

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Infrastructure

• Available iPaqs, laptops, PCs, pcmcia cards
• Sophisticated infrastructure and testbed for
  networking measurements
• Lab for measurements on energy consumption

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Second Local UNC-CH Workshop on mobile computing

• First Local UNC-CH Workshop on Mobile Computing
• Invite people from industry (Microsoft, IBM)
• Possibilities for collaboration with researchers
  from industry
• Summer internships
• Funding possibilities

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Seminar Topics

• Wireless data access IEEE 802.11
• Mobile peer-to-peer systems
• Location-sensing systems
• Location-dependent services
• Energy measurements conservation
• Measurements on wireless networks
• Routing protocols for mobile devices
• Information discovery in peer-to-peer systems
• Security issues on wireless access

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Wireless Data Access

• Wireless data access
• Bluetooth, CDPD, 3G, Ricochet, sensors, wireless
  LAN
• Prefetching hoarding
• IEEE 802.11 Wireless LAN
• Physical layer
• MAC layer
• Management functions
• Some QoS issues

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7DS Resource sharing among mobile clients

• Location-dependent applications spatial
  locality of information
• Design challenges
• User interfaces
• Populating caches
• Routing filtering queries
• Energy conservation
• Performance study via simulations, analysis
  measurements
• Implementation improvements of prototype

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Peer-to-Peer systems

• Peer-to-peer systems on wired network
• Napster
• Free riding on Gnutella
• Freenet
• Small-world models and random graphs
• The small world problem phenomenon
• An algorithmic approach
• Using the small-world model to improve Freenet
  performance

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Location-sensing systems

• Application requirements affect the decision for
  location-sensing
• Environment, accuracy, coverage, infrastructure,
  power, cost
• Different modalities of communication
• RF, ultrasound, infrared, video, or combination
  of the above
• Using different signal characteristics
• Time-of-arrival, strength, signature

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Energy measurements energy conservation
mechanisms

• Energy dissipation measurements of the wireless
  interface
• Energy conservation mechanisms
• Performance goals
• Minimize adverse on capacity, throughput, packet
  latency
• Fairness among participants, system lifetime
• 802.11b PS mode
• SPAN

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Wireless Traffic Measurements

• Wireless traffic characterization network
  performance
• Comparison with traffic from wired users
• Users access pattern
• Popular applications
• Spatial locality of information
• Mobile clients association with an access point
• Duration frequency
• Mobility pattern

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Sensor Networks

• Sensors actuators (hardware, challenges in
  building networks)
• Information discovery and data management in
  sensor networks
• Communication cost for different models
• Routing queries
• Locating tiny sensors in time and space

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Routing Protocols for Mobile Clients

• Ad hoc networks
• DSR
• AODV
• Location-based routing
• Wireless WAN using infrastructure
• Mobile IP
• Using SIP

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Paper presentation

• Team of two students
• Paper preparation with another student
• 20 minutes presentation of a paper by one student
• Two paper presentations at each lecture on the
  same topic
• In each lecture at the end of the second
  presentation, critical analysis of the two papers
  and discussion
• The two teams of students lead the discussion

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Critical review and discussion

• Main contributions of the paper
• Differences from related work
• Clever ideas and techniques in the paper
• Weaknesses (eg, technical errors, unrealistic
  assumptions, unanswered questions, limited
  measurements)
• Ways to improve the paper technically
• Interesting topics discussed in its future work
• Ideas for extending the paper

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Comparison of the two papers

• Each pair of students defends the paper they have
  prepared
• They can include their own ideas as possible
  extensions of the paper
• The two teams lead the discussion
• Class participate in the discussion

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Project topics

• Location-based applications
• Interactive editing of maps
• Superimpose textual or audio information on a map
• Note sharing application
• Notification mechanism for reminders or
  location-dependent data
• Test, improve, and evaluate

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Project topics

• Energy conservation
• Design algorithms and evaluate them
• Measurement of the wireless infrastructure in UNC
  campus
• Wireless traffic characterization
• User mobility pattern characterization
• Location-sensing system
• Design algorithms and evaluate them

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Project topics 7DS-related

• Application data and querying using XML
• Prefetching
• User interfaces
• Notification for incoming data
• Keyword search
• Integrate applications with 7DS
• 7DS underlying information-discovery mechanism

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Project topics

• Data dissemination across mobile devices
• Impact of cache
• Expiration, size
• Routing of queries
• Simulation using ns-2
• Analysis (theoretical issues epidemic models,
  random graphs, diffusion)

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Other Project Topics

• Integration of 7DS with other mobile,
  location-dependent or virtual-reality
  applications ?
• Open to student suggestions

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Project Assignment

• Description
• Checkpoints
• Milestones
• Project evaluation
• Design review
• Code review
• Presentation demo
• Report
• Midterm evaluation of the project

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Project meetings

• Meet with me or TA
• Twice a week for the first one month
• Then, once a week for next one month
• Depending on the progress the meeting will be
  once a week or once-two weeks for the last month
• Mid-term project review and evaluation

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Examples of projects from last semester

• Location-sensing
• Energy-conservation
• Measurement study
• Note-sharing tool
• Interactive map editing for mobile users

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Finishing up

• Undergrad students less workload
• Strength or interest for project assignment
• Email me
• Comments questions ?