1. Scalable and Robust Data Dissemination in Wireless Sensor Networks Wei Liu, Yanchao Zhang, Yuguang Fang, Tan Wong Department of Electrical and Computer Engineering University of Florida IEEE Globecom 2004

2. Outline  Introduction  A Hybrid Data Dissemination Framework For Sensor Networks  Performance Evaluation  Conclusion

3. Introduction  Flooding is a technique with inbred reliability  It seems to be good for sensor networks without Topology maintenance Complex route discovery algorithms  The main problems with flooding are Bandwidth congestion Inefficient use of energy

4. Introduction  A hybrid data dissemination framework for WSNs is proposed in this paper A sensor field is partitioned into several functional regions A novel zone flooding scheme  A combination of flooding and geometric routing

5. A Hybrid Data Dissemination Framework For Sensor Networks  Manufacture area  Transportation area  Warehouse area  Service area

6. A Hybrid Data Dissemination Framework For Sensor Networks Manufacture areaTransportation area Warehouse areaService area

7. A Hybrid Data Dissemination Framework For Sensor Networks  Manufacture area Nodes are aware of their sensing tasks  Beak color  Feet length  Bird chirms Data Aggregation center will  Collect and aggregate the data  Transport the data through transportation area

8. A Hybrid Data Dissemination Framework For Sensor Networks  Transportation area Sensor nodes undertake the task of relaying data to sink nodes Zone flooding scheme is proposed as the routing protocol  Avoid costly topology maintenance and complex route discovery scheme  Combination of geometric routing and flooding

9. A Hybrid Data Dissemination Framework For Sensor Networks

10. f1 f2 a b c P(x 1,y 1 ) R3(x 3,y 3 ) U d(U,f1)+d(U,f2)=2a U’U’ U”U” d(U ’,f1)+d(U ’,f2)<2a d(U ”,f1)+d(U ”,f2)>2a a 2 =b 2 +c 2

11. A Hybrid Data Dissemination Framework For Sensor Networks f1 f2 a b c P(x 1,y 1 ) R3(x 2,y 2 ) U(x 3,y 3 ) d(U,f1)+d(U,f2)=2a c

12. A Hybrid Data Dissemination Framework For Sensor Networks

13.  Random Access Delay(RAD) 0~T max Each node needs to rebroadcast if not receiving redundant packets during the RAD Eliminate unnecessary transmissions Reduce the collisions among neighboring nodes

14. A Hybrid Data Dissemination Framework For Sensor Networks

15. Warehouse area and service area

16. Performance Evaluation

20. Conclusion  This paper proposes a hybrid dissemination framework for WSNs  The whole network can be partitioned into several functional regions  It has high reliability, good scalability, and notable flexibility