Broadcast Scheduling in Mobile Ad Hoc Networks

1. Broadcast Scheduling in Mobile Ad Hoc Networks ——Related work and our proposed approach By Group 4: Yan Qiao, Yilin Shen, Bharat C. and Zheng Li Presenter: Zheng Li zhengli@ufl.edu

2. Existing broadcast scheduling approaches for MANET • Blind flooding • Self/dominant pruning • PDP and TDP • Forward-node-set-based broadcast

3. Existing broadcast scheduling approaches for MANET • Blind flooding • Self/dominant pruning • PDP and TDP • Forward-node-set-based broadcast

4. Existing broadcast scheduling approaches for MANET • Blind flooding • Self/dominant pruning • PDP and TDP • Forward-node-set-based broadcast

5. Self Pruning and Dominant Pruning • Optimal flooding tree (NP-C) • Minimize the cost - the number of transmissions • Utilize the neighborhood information exchanged between nodes • Nodes keep reporting their existence to neighbors Reference: H. Lim and C. Kim, “Flooding in wireless ad hoc networks.”

6. Self Pruning

7. Dominant Pruning

8. Self Pruning and Dominant Pruning • Weakness • Overhead!! “smart” routing • more information needed • increased overhead for transmission Reference: H. Lim and C. Kim, “Flooding in wireless ad hoc networks.”

9. Existing broadcast scheduling approaches for MANET • Blind flooding • Self/dominant pruning • PDP and TDP • Forward-node-set-based broadcast

10. Existing broadcast scheduling approaches for MANET • Blind flooding • Self/dominant pruning • TDP and PDP • Forward-node-set-based broadcast

11. TDP and PDP • Total/partial dominant pruning • Utilized the neighborhood information more effectively • Further reduced broadcast redundancy Reference: W. Lou and J. Wu “On Reducing Broadcast Redundancy in Ad Hoc Wireless Network”

12. TDP and PDP • Work well in the average case, but not good in dense networks • Approximation ratio O(n) • Can be extended to a clustered network • A constant approximation ratio can be achieved

13. Existing broadcast scheduling approaches for MANET • Blind flooding • Self/dominant pruning • PDP and TDP • Forward-node-set-based broadcast

14. Forward-node-set-based broadcast • Process • Clustering and one clusterhead for each cluster • Transmit the message to the clusterhead • Clusterhead choose its forward-node-set to reach the clusterheads within the range. Information of forward clusterheads and forward nodes piggybacked • Nodes retransmit the message or do nothing Reference: J. Wu and W. Lou “Forward-Node-Set-Based Broadcast in Clustered Mobile Ad Hoc Networks.”

15. Forward-node-set-based broadcast Reference: J. Wu and W. Lou “Forward-Node-Set-Based Broadcast in Clustered Mobile Ad Hoc Networks.”

16. Forward-node-set-based broadcast • Constant approximation ratio • Number of forward nodes relatively stable • Dense (all nodes) => sparse (clusterheads) • Heavy overhead • Forward-clusterhead-set • Forward-node-set • Clustering by group Reference: J. Wu and W. Lou “Forward-Node-Set-Based Broadcast in Clustered Mobile Ad Hoc Networks.”

17. Existing broadcast scheduling approaches for MANET • Blind flooding • Self/dominant pruning • PDP and TDP • Forward-node-set-based broadcast

18. Existing broadcast scheduling approaches for MANET • Blind flooding • Self/dominant pruning • PDP and TDP • Forward-node-set-based broadcast

19. Broadcast scheduling in WSN • Interference-aware broadcasting • Hexagonal tiling • Coloring • Static WSN • … Reference: Ravi Tiwari, Thang N. Dinh, and My T. Thai “On Approximation Algorithms for Interference-Aware Broadcast Scheduling in 2D and 3D Wireless Sensor Networks.”

20. Our approach • Hexagonal tilling • Coloring to avoid interference • Details had been covered • … • Less assumptions, more realistic • Transmission/interference range • Local • Based on local information, group model

21. Compare with FNSB approach • Overhead: • FNSB need to keep two lists • Forward clusterheads and forward nodes • Latency: • FNSB selects the FNS every time

22. Thank you!Questions?