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Optimizing the Topology of Bluetooth Wireless Personal Area Networks

Marco Ajmone Marsan, Carla F. Chiasserini, Antonio Nucci, Giuliana Carello, Luigi De Giovanni

IEEE INFOCOM 2002

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Outline Introduction Problem Statement Integer Linear Programming (ILP)

formulation Numerical Results Conclusion

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Introduction(1) Wireless Personal Area Network (WPAN)

Short-range battery-operated radio devices 2.4GHz ISM band FHSS

Bridges Re-synchronize with the piconets imply a

significant overhead that effect the system performance

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Introduction(2) The role of a node

Master of Slave? Selection has a significant impact on

the capacity and the throughput of the system.

Former researches are not suitable Single channel communication? Transmit power control?

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Problem Statement Full network connectivity System specification System complexity Traffic requirement Constraints on the nodes’ role

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ILP Formulation(1) Notation

N : the set of network nodes Z : the matrix containing the values of the distances between any two nodes S : the set of traffic sources D : the set of destination nodes Zmax : the maximum radius of a piconet

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ILP Formulation(2)

the set of source-destination connections C=|C| , the total number of connection through this network T={tij} be the traffic matrix indication the information rate on each source-destination connection

},:),{( DdSsdsC

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ILP Formulation(3) Ps : the total average traffic rate Mmax : maximum number of piconets Xmax : maximum number of active nodes that can be assigned to a piconet M : node that are forced to be masters

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ILP Formulation(4)

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ILP Formulation(5)

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ILP Formulation(6)

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ILP Formulation(7)

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ILP Formulation(8)

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ILP Formulation(9)

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Example(1)

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Example(2)

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Example(3)

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Example(4)

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Numerical Results(1)

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Numerical Results(2)

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Numerical Results(3)

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Conclusion Optimized topologies can be quite

robust to changes in the traffic pattern

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Discussion Centralized or distributed solution?

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Thank You