CEN4500C: Wireless Experiments Background - PowerPoint PPT Presentation
Title:
CEN4500C: Wireless Experiments Background
Description:
How does a coverage map look like? http://www.ittc.ku.edu/wlan ... (emulator) SNR v.s. Delivery ratio (real measurement) SNR v.s. TCP Tput (real measurement) ... – PowerPoint PPT presentation
Number of Views:55
Avg rating:3.0/5.0
Title: CEN4500C: Wireless Experiments Background
1
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
2
Part I Wireless MeasurementsAgenda
- Introduction
- Wireless measurement fundamentals
- Tools
- Potential Topics
- Reference
3
How does a coverage map look like?
4
coverage maps (contd)
5
Wireless fundamentals SNR v.s. Distance
6
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)
7
Tools
- Site-surveyer Netstumbler (www.netstumbler.com)
- Signal (in dbm), SNR
- AP MAC, SSID
8
(No Transcript)
9
Tools (contd)
- HP iPAQ
10
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
11
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.)
12
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
13
Part II Encounter-based Networks Agenda
- Introduction
- Examples of Encounter based networking
- Encounter-based worm interactions
- Experiment for our class
- Reference
14
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
15
Examples of encounter-based networks
- Military tactical networks
- Disaster relief
- ZebraNet
- Interplanetary networks
- Underwater acoustic networks
- Rural village networks
- Other?
16
http//www.cs.rice.edu/animesh/comp620/presentati
ons/JFP04_D.pdf
17
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
18
Encounter-based worm interaction
Susceptible
Predator
Prey
Prey and predators infection rate rely only on
encounter characteristics
19
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.
20
- 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
21
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.
Recommended
CrystalGraphics Presentations
