Considering PCF for WSN

1. Presenter: Jae Weon Choi Affiliation: Graduate School of Convergence IT Considering PCF for WSN

2. Motivation • Collision worsen • Power Waste Issue • Delivery Latency Issue • Delivery Completion Rate • Collision Happen because Contention Based Multi Access Approach has been taken • In addition, Collision Avoidance has overhead • Using PCF Network can become Collision-Free

3. PCF Adaptation • 계층 형 WSN • Cycle 분활 형 • Cycle 순례 형

4. PCF Adaptation(cont.) • Cycle 분활 형 (No Buffer) • Cycle=(Sum((End node Number)*(Node Limit)^N))*2 while N = {0…(Number of Layer-1)} • Retransmission period = Cycle

5. PCF Adaptation(cont.)

6. PCF Adaptation(cont.) • Cycle 분활 형 (With Buffer) • Cycle = (Node Limit) * 3 * (Transmission Time) • Retransmission period = Cycle

7. PCF Adaptation(cont.)

8. PCF Adaptation(cont.) • Cycle 순례 형 • Cycle = 3 * (Transmission Time) • Retransmission period = Cycle * (End Node Number)

9. PCF Adaptation(cont.)

10. Expected Result of PCF • Increase in Delivery Completion Rate • More Accurate estimation of Latency • No Power waste due to collision

11. Problems Found • Increase in Cycle Time and Delivery Latency • Increase in Idle Listening • Collision Still exist • Complicated Network Initialization

12. Why do Collision Still Exist? • When 1-1-2 is registered at 1-1-0 and 1-2-1 is registered at 1-2-0 • When 1-1-2 and 1-2-1 was assigned same sending Period • It does not happen at Cycle 순례 형

13. Conclusion • Currently, not Competent • Adaptive Wakeup Scheduling Used SPEED MAC May Improve it • Utilizing PCF just for Multi-Source Traffic Mode

14. 즐거운 겨울 되세요. 감사합니다.