1. Sensor Network Architectures muse

2. Objectives Be familiar with how application needs impact deployment strategies Understand key benefits/costs associated with different topologies. Understand key benefits/costs associated with homogeneous and heterogeneous node deployments muse

3. Objectives (cont.) Apply simple metrics to assess network connectivity Understand common routing protocols Synthesize these concepts to ascertain the energy requirements for various network topologies muse

4. Outline Deployment strategies Network topologies Connectivity and Coverage Routing protocols Example Application: Energy use for various topologies

5. Deployment Strategies Motivation Application needs? Deployment

6. Random vs. Structured RandomStructured Deployment

7. Incremental vs. Over-deployment IncrementalOver-deployment Deployment

8. Outline Deployment strategies Network topologies Connectivity and Coverage Routing protocols Example Application: Energy use for various topologies

9. Network Topologies Motivation Star – single hop Flat mesh – multi-hop Tiered – multi-hop Topologies

10. Star Topologies

11. Mesh Topologies

12. Tiered Topologies

13. Node Capabilities HomogeneousHeterogeneous Topologies

14. Single vs. Multi-hop Single hopMulti-hop Topologies

15. Outline Deployment strategies Network topologies Connectivity and Coverage Routing protocols Example Application: Energy use for various topologies

16. Connectivity Motivation Graph Theory Tools Connectivity

17. Random Graph Model G(n,R) Connectivity

18. Graph Connectivity Connectivity

19. Problem with Random Graph Model Propagation environments are not isotropic Connectivity

20. K-connectivity Connectivity

21. Improving connectivity ApproachesCosts Connectivity

22. Outline Deployment strategies Network topologies Connectivity and Coverage Routing protocols Example Application: Energy use for various topologies

23. Coverage Motivation Tools Coverage

24. Voronoi Diagram Coverage

25. K-coverage Coverage

26. Example Coverage

27. Problems with Coverage Metrics Coverage

28. Topology Control Idea Motivation Topology Control

29. Method 1: PEAS Topology Control

30. Method 2: ACK Topology Control

31. Outline Deployment strategies Network topologies Connectivity and Coverage Routing protocols Example Application: Energy use for various topologies

32. Routing protocols Motivation Metric-based Diversity-based Routing protocols

33. Greedy Forwarding Routing protocols

34. ETX Metric Routing protocols

35. Opportunistic (ExOR) Routing protocols

36. Gradient-based Routing protocols

37. Lifetime and Load-balancing LifetimeLoad Routing protocols

38. Data Mules Routing protocols

39. Outline Deployment strategies Network topologies Connectivity and Coverage Routing protocols Example Application: Energy use for various topologies

40. Comparison: Single-hop vs. Double-hop Networking & Energy

41. Scenario 2: Single-hop vs. Double-hop Networking & Energy

42. Conclusions Multi-hop networks promise broader coverage and robustness at the cost of increased complexity Homogeneous node architectures simplify deployment strategies but may require more capable hardware Node connectivity is dependent on the node placement and the communication channel muse

43. Conclusions - 2 Network coverage requirements may not coincide with network connectivity requirements Routing schemes depend on defining an appropriate ‘cost’ metric Network architectures drive node and system design and therefore energy and bandwidth requirements muse

44. Want to learn more? B. Krishnamachari, Networking Wireless Sensors, Cambridge Press (2005). H. Karl and A. Willig, Protocols and Architectures for Wireless Sensor Networks, Wiley (2007).