1. Márk FélegyháziMaster’s Thesis Development and Evaluation of a Dynamic Bluetooth Network Formation Procedure Márk Félegyházi, György Miklós Ericsson Research, Hungary mark@sch.bme.hu

2. Márk FélegyháziMaster’s Thesis Overview •Bluetooth wireless technology •Network formation in Bluetooth •Suggested methods –two methods for network building –network topology optimization •Simulation results •Conclusion

3. Márk FélegyháziMaster’s Thesis Bluetooth wireless technology (1) • short-range radio technology • cable replacement • universal interface Internet

4. Márk FélegyháziMaster’s Thesis Bluetooth wireless technology (2) •master-slave relationship between nodes •Frequency Hopping (FH) •Time Division Duplex (TDD) communication master slave

5. Márk FélegyháziMaster’s Thesis Bluetooth network piconetscatternet

6. Márk FélegyháziMaster’s Thesis Bluetooth scatternet formation A B

7. Márk FélegyháziMaster’s Thesis Problem formulation •Connection setup phase –neighbour discovery –physical connection setup •Scatternet building and maintenance •Scatternet optimization

8. Márk FélegyháziMaster’s Thesis Alive Broadcasting Scatternet Building method (ABSB) A E D C B F sending Alive messages (limit=3) A E D C B F Fully-connected network A E D C B F connection breakdown

9. Márk FélegyháziMaster’s Thesis Routing Based Scatternet Building method (RBSB) A E D C B F

10. Márk FélegyháziMaster’s Thesis Traffic Dependent Scatternet Optimization (TDSO) A B C A B C simple piconet connection setup A B C master-slave switch A B C connection teardown

11. Márk FélegyháziMaster’s Thesis Ad hoc module in PLASMA

12. Márk FélegyháziMaster’s Thesis Dynamic scatternet formation with the ABSB method time (s) throughput (kbit/s) (a) (b) (c) (d) (e) (f)

13. Márk FélegyháziMaster’s Thesis Simulation results of the scatternet optimization T execution = 1 sT execution = 4 s time [s] throughput [bit/s]

14. Márk FélegyháziMaster’s Thesis Conclusion • Bluetooth Scatternet Building – two methods (ABSB and RBSB) – simple methods – distributed algorithms – periodic messaging (robust against packet loss) • Bluetooth Scatternet Optimization (TDSO) – distributed algorithm – decisions according to local measured traffic • Simulation results – scatternet building – fully-connected network building and maintenance – scatternet optimization – increases network capacity by reconfiguring the topology

15. Márk FélegyháziMaster’s Thesis Future work •Implementation of the routing based scatternet building method •Performance evaluation of the alive based scatternet building method •Measurements with the tuning of the parameters in the scatternet optimization method •Test both scatternet building and optimization procedure together