1 cooperation in multi-domain sensor networks márk félegyházi levente buttyán jean-pierre hubaux...

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Cooperation in Multi-Domain Sensor Networks

Márk Félegyházi Levente ButtyánJean-Pierre Hubaux

{mark.felegyhazi, jean-pierre.hubaux}@epfl.ch

EPFL, Switzerland

TERMINODES Project (NCCR-MICS)http://www.terminodes.org

buttyan@hit.bme.hu

Budapest University of Technology and Economics, Hungary

PerSeNS 2005.03.08

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Multi-domain sensor networks

co-located sensor networks sensors are compatible sinks can be either separate or common

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Non-cooperative game assumption: paths to the sink exist in both own and

common network the game unfolds in discrete time steps t lifetime of sensor networks: until the first sensor dies finite routing game: ends when one subnetwork dies

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Benefits of cooperation operators as players two decisions:

ask (or not) the other player to cooperate cooperate (or not) if asked

reduce complexity: strategy is pre-defined in the sensors

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Strategies success of data gathering: if

moves:

strategy:

i it SR

i twhere:

is the gathered number of measurements

is the requirement for successiSR

pre-programmed strategy in the sensors

feedback in one bit from the sink (successful or not)

• DD - don't ask/drop• DF - don't ask/forward• AD - ask/drop• AF - ask/forward

success XX

next move XX XX DD, DF, AD, AF

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Utilities

gain, gi(t): if the step was successful,

then gi(t) = Gi

otherwise gi(t) = 0 cost, ci(t): sum of the transmission cost of all

sensors (cunit ~ dα) payoff, utility:

0

T

i it

U t

where: T is the lifetime of the sensor network

i it SR

i i it t c t g

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Simulation parameters

Number of sensors per domain 10 - 50 (25)

Distribution of the sensors uniformly random

Area size 40 x 20 m

Reception energy (R) 100 units

Transmission energy (Tr) Tr ~ dα units

Path loss exponent 2 – 5 (4)

Success requirement (SRi) 1.0 (all sensors have to report)

Position of the sinks (separate sinks) [10,10] and [30,10]

Position of the sinks (common sinks) [20,10]

Route selection Minimum energy path

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Best strategies

Three types: Cooperative: (AF, AF) Defective: (DD, DD) Other: for example (AF, DD)

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Simulations: Separate sinks

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Simulations: Common sinks

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Simulations: Path loss exponent

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Conclusion

Cooperation is beneficial, because it can increase the lifetime of sensor networks.

For separate sinks, operators can use the sinks of each other

For common sinks, cooperation is beneficial: if sensor networks are sparse – overhearing of

packets is less significant if path loss is high - transmission is expensive