CEN4500C: Wireless Experiments Background

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CEN4500C Wireless Experiments Background

• Wireless Measurements Shao-Cheng Wang (
  shaochew_at_ufl.edu )
• Encounter-based Networks Sapon Tanachaiwiwat (
  stanachai_at_gmail.com )
• Instructor Dr. Helmy
• 9/13/2007

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Part I Wireless MeasurementsAgenda

• Introduction
• Wireless measurement fundamentals
• Tools
• Potential Topics
• Reference

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How does a coverage map look like?
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coverage maps (contd)
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Wireless fundamentals SNR v.s. Distance
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Wireless fundamentals SNR v.s. Performance
SNR v.s. Delivery ratio (emulator)
SNR v.s. Delivery ratio (real measurement)
SNR v.s. TCP Tput (real measurement)
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Tools

• Site-surveyer Netstumbler (www.netstumbler.com)
• Signal (in dbm), SNR
• AP MAC, SSID

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(No Transcript)
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Tools (contd)

• HP iPAQ

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Tools (contd)

• Bandwidth test
• NDT _at_ UF http//ndt.server.ufl.edu7123/
• TCP uplink/dnlink speed
• Myspeed http//myvoipspeed.visualware.com/
• UDP loss rate, jitter

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Potential experiment topics

• Coverage Map
• Create a coverage map of your choice
• SNR (enhanced with levels, dbm s)
• SNR variations (weather, day/night)
• Performance map
• Find holes, additions, tech heterogeneity
  (11a/b/g/e/n) etc.
• (please coordinate between groups for the area of
  interest)
• Reason about your choice and the implications of
  practicability
• Observations/Surprises?
• AP Hunting/Coverage/Handover
• Locate APs in some specific areas/buildings
• Create an AP-specific coverage map
• AP-coverage/handover map for routes on campus
• Observations and discussions about the AP
  planning (evaluation of planning, tradeoffs,
  applications, etc.)

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Reference

• Simon Byers and Dave Kormann, 802.11b access
  point mapping, Communications of the ACM, May
  2003.
• Daniel Aguayo, John Bicket, Sanjit Biswas, Glenn
  Judd, Robert Morris, Link-level Measurements
  from an 802.11b Mesh Network, SIGCOMM 2004,
  August 2004
• Hiroto Aidal, Yosuke Tamura2, Yoshito Tobe2,
  Hideyuki Tokudal, Wireless Packet Scheduling
  with Signal-to-Noise Ratio Monitoring, LCN 2000

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Part II Encounter-based Networks Agenda

• Introduction
• Examples of Encounter based networking
• Encounter-based worm interactions
• Experiment for our class
• Reference

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Introduction

• What is Encounter-based networking
• Discontinuous path (Intermittent connection)
• Store-and-forward (Bundles)
• Similar to delay-and-disruption-tolerant-networkin
  g
• Large delay
• Low data rate
• High loss rate
• Networking relying on encounter or relationships
  between nodes (Social networking)
• Basic assumptions of each node
• Persistent storage
• Willing to participate
• Limitation of Power
• Short Radio Range

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Examples of encounter-based networks

• Military tactical networks
• Disaster relief
• ZebraNet
• Interplanetary networks
• Underwater acoustic networks
• Rural village networks
• Other?

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http//www.cs.rice.edu/animesh/comp620/presentati
ons/JFP04_D.pdf
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Encounter-based worms

• Future direction on worm attacks!! (Cabir,
  ComWar)
• Rely on encounter pattern/relationships between
  users.
• Close to flooding, i.e. Epidemic routing.
• Propagate via Bluetooth connection (10-meter
  range)
• Question How can we alleviate this problem?
• Traditional prevention at gateway such as
  firewall not effective against fully distributed
  attacks
• Disconnected networks ? No centralized update
• Inspired by War of the Worms CodeGreen worms
  launched to terminate CodeRed worms
• Approach Deploy automated generated predator
  worm to terminate prey worm ? worm interaction

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Encounter-based worm interaction
Susceptible
Predator
Prey
Prey and predators infection rate rely only on
encounter characteristics
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Experiment

• Goal To answer the following questions
• Is the UF campus the good target for worm
  propagation, given that it propagate via
  Bluetooth?
• If so, what places are most vulnerable?
• If you want to stop the propagation with other
  worm, how can you do it effectively?
• Equipments iPAQs, your laptops, your strategies
• Software Modified Bluechat, Netstumbler,
  AirSnort, etc.

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• Bluetooth device discovery
• Distribution of Bluetooth devices that you
  encounter during the day
• E.g. Type of devices such as cell phone or lap
  top, brand of such devices such as Nokia,
  Motorola, etc.
• Bluetooth game ? Design the strategies for
• Largest of encounter rate per day
• Largest number of unique devices
• Largest number of stable devices
• Different roles between teams e.g. Cops and Cons
• Bluetooth and WLAN relationships
• Can you derive the correlation between them?
• Bluetooth worm interactions
• To test the real worm propagation/ interaction
  with static/mobility
• Parameters
• Type of worm one or two
• Static or Mobile (human mobility)
• Topology (for static) line, star, random
• With/Without the super node, i.e., super mobile
  node which is our radio-controlled truck

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Reference

• E. Anderson, K. Eustice, S. Markstrum, M. Hansen,
  P. L. Reiher , Mobile Contagion Simulation of
  Infection and Defense PADS 2005 80-87
• S. Capkun, J. P. Hubaux, and L. Buttyan "Mobility
  Helps Security in Ad Hoc Networks" Fourth ACM
  Symposium on Mobile Networking and Computing
  (MobiHoc), June 2003
• F. Castaneda, E.C. Sezer, J. Xu, WORM vs. WORM
  preliminary study of an active counter-attack
  mechanism, ACM workshop on Rapid malcode, 2004
• A. Chaintreau, P. Hui, J. Crowcroft, C. Diot, R.
  Gass and J. Scott, Impact of Human Mobility on
  the Design of Opportunistic Forwarding
  Algorithms IEEE INFOCOM, April 2006
• W. Hsu, A. Helmy, "On Nodal Encounter Patterns in
  Wireless LAN Traces", The 2nd IEEE Int.l Workshop
  on Wireless Network Measurement (WiNMee), April
  2006
• S.Tanachaiwiwat, A. Helmy, "Encounter-based
  Worms Analysis and Defense", IEEE Conference on
  Sensor and Ad Hoc Communications and Networks
  (SECON) 2006 Poster/Demo Session, VA, September
  2006
• A. Vahdat and D. Becker. Epidemic routing for
  partially connected ad hoc networks. Technical
  Report CS-2000.