1. 1 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

2. 2 Outline Introduction Problem Statement Integer Linear Programming (ILP) formulation Numerical Results Conclusion

3. 3 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

4. 4 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?

5. 5 Problem Statement Full network connectivity System specification System complexity Traffic requirement Constraints on the nodes ’ role

6. 6 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 Z max : the maximum radius of a piconet

7. 7 ILP Formulation(2) the set of source-destination connections C=|C|, the total number of connection through this network T={t ij } be the traffic matrix indication the information rate on each source- destination connection

8. 8 ILP Formulation(3) P s : the total average traffic rate M max : maximum number of piconets X max : maximum number of active nodes that can be assigned to a piconet M : node that are forced to be masters

9. 9 ILP Formulation(4)

10. 10 ILP Formulation(5)

11. 11 ILP Formulation(6)

12. 12 ILP Formulation(7)

13. 13 ILP Formulation(8)

14. 14 ILP Formulation(9)

15. 15 Example(1)

16. 16 Example(2)

17. 17 Example(3)

18. 18 Example(4)

19. 19 Numerical Results(1)

20. 20 Numerical Results(2)

21. 21 Numerical Results(3)

22. 22 Conclusion Optimized topologies can be quite robust to changes in the traffic pattern

23. 23 Discussion Centralized or distributed solution?

24. 24 Thank You