Title: SOWER: Self-Organizing Wireless Network for Messaging
1SOWER 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
2SOWER Self-Organizing Wireless Network for
Messaging
- Intro to ad hoc networks
- Motivation
- System approach
- Connectivity investigations measurement and
simulations - Conclusion and future work
3Ad Hoc Networks
- self-organizing network no infrastructure
- each networking service is provided by the nodes
themselves - devices powered by a battery energy constraints
4Motivation 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
5A 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
6Connectivity 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
7Connectivity 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.
8Connectivity and coverage simulation parameters
Investigate the connected component of home
devices
Home devices uniformly placed in the buildings.
9Connectivity 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
10Connectivity simulations in 3D
Skyscrapers
Small buildings 5 floors
11Penetration 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
12Conclusion
- 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
13Additional 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
14Future 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