SOWER: Self-Organizing Wireless Network for Messaging

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SOWER Self-Organizing Wireless Network for
Messaging
Srdjan Capkun
Márk Félegyházi
Jean-Pierre Hubaux
mark.felegyhazi, srdan.capkun,
jean-pierre.hubaux_at_epfl.ch
Laboratory for computer Communications and
Applications, Swiss Federal Institute of
Technology (EPFL) Lausanne, Switzerland
TERMINODES Project (NCCR-MICS) http//www.terminod
es.org
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SOWER Self-Organizing Wireless Network for
Messaging

• Intro to ad hoc networks
• Motivation
• System approach
• Connectivity investigations measurement and
  simulations
• Conclusion and future work

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Ad Hoc Networks

• self-organizing network no infrastructure
• each networking service is provided by the nodes
  themselves
• devices powered by a battery energy constraints

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Motivation Cellular Networks

• Short Messaging (SMS)
• a simple way of communication ? popular
• does not require high bandwidth
• delay tolerant (in the order of tens of seconds /
  minutes)
• BUT
• price of SMS is extremely high
• infrastructure of base stations is complex and
  expensive deployment and maintenance costs
• users have no alternative
• Future vision
• self-organizing and robust short messaging
• new services / applications

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A Self-Organizing Wireless Messaging Network
(SOWER)
Each user owns
home device
mobile device
m

• Home devices are
• power plugged always on
• static devices
• same radio as mobiles

Home devices form a wireless backbone for message
transmission
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Connectivity measurements (1/2)
Measurement campaign 500m 500m in Lausanne
center

• Parameters
• laptops with 801.11b wireless _cards
• random measurement points
• 1 Mbit/s channel capacity
• 100 mW transmission power

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Connectivity measurements (2/2)
Main observation With the device density equal
to 220 devices/km2, we can provide a messaging
network in a small city with a high coverage.
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Connectivity and coverage simulation parameters
Investigate the connected component of home
devices
Home devices uniformly placed in the buildings.
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Connectivity and coverage simulations in 2D
Coverage The proportion of the covered area of
the largest connected component
Connectivity The proportion of the largest
connected component
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Connectivity simulations in 3D
Skyscrapers
Small buildings 5 floors
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Penetration requirements
Scenario
modern (Berlin)
ultra-modern (Manhattan)
small (Berkeley)
historic (Rome)
Population density (persons/km2)
25850
2260
8177
12500
Required device density (devices/km2)
700
3000
5000
380
Required market penetration (simulation for
100mW)
0.086
0.24
0.193
0.168
Required market penetration (calculated for 1W,
a5)
0.06
0.04
0.02
0.05
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Conclusion

• SOWER All-wireless messaging network in cities
• self-organizing messaging network
• city-wide connectivity can be achieved with low
  market penetration
• capacity is sufficient to support messaging

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Additional technical issues

• Deployment of the network
• using existing infrastructure (dual-mode devices)
• higher transmission power (1 W in the US)
• Access to the infrastructure
• cellular networks
• high-speed Internet connections
• Capacity
• links have higher transmission rate (up to 54
  Mbit/s nowadays)
• Addressing Routing
• Security
• end-to-end security
• trust issues
• cooperation
• Pricing
• secure micropayment mechanism

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Future work

• extensive measurements in different city
  scenarios
• routing issues include mobile devices in the
  packet forwarding
• charging and security issues
• implementation

• More info
• web gtgt http//lcawww.epfl.ch/felegyhazi/
• email gtgt mark.felegyhazi_at_epfl.ch