1. Bandwidth Constrained Energy Efficient Transmission Protocol in Wireless Sensor Networks Jain-Shing LIU and Chun-Hung Richard LIN,Nonmembers IEICE TRANS. COMMUN.,VOL.E86-B,NO.10 OCTOBER 2003 SPEAKER: Hsu-Jui Chang

2. Outline Introduction Power-Efficiency Clustering Method Dynamic Transmission Range Control Protocol (DTRCP) Cluster Head Election Protocol (CHEP) Power Limit Constraint Performance Evaluation Conclusion

3. Introduction (1/6) Sensor ： Capability of programming computing, multiple parameter sensing, wireless communication Composition of sensor node CPU and memory Power (battery) Wireless communication device Sensor

4. Introduction (2/6) Design an effective multi-hop communication architecture and protocol maximizing point-to-point throughput minimizing network delay Power-conserving design in ad hoc wireless networks low-power I/O devices efficient algorithms

5. Introduction (3/6) Power-consumption problems Allow the power to the nodes “ on ” during their entire lifetime Allow these nodes to become hotspots Alleviate these problems minimum energy routing saves power by adopting paths distributing energy consumption

6. Introduction (4/6) Routing protocols that concern minimizing the total transmit energy maximizing the network lifetime The clustering method has investigated enhance network manageability channel efficiency provide routing or multicasting scalability

7. Introduction (5/6) One drawback of cluster Cluster-heads are communication centers by default Heavily utilized and the battery power is drained quickly Power-Efficiency Clustering Method (PECM)

8. Introduction (6/6) -abstract Power-Efficiency Clustering Method Dynamic Transmission Range Control Protocol (DTRCP) Transmission Range Expanse and Neighborhood Establishment Transmission Range Shrink and Neighborhood Denial Cluster Head Election Protocol (CHEP) Partitioning stage Choosing stage Hierarchy clustering stage Power Limit Constraint

9. Dynamic Transmission Range Control Protocol (DTRCP)

10. Cluster Head Election Protocol (CHEP) -Partitioning stage

11. Cluster Head Election Protocol (CHEP) -choosing stage

12. Cluster Head Election Protocol (CHEP) -hierarchy clustering stage

13. Power-Efficiency Clustering Method

14. Power-Efficiency Clustering Method (1/2) Designed to dynamically change the role of coordinator in a cluster Balance the power consumption under the whole network ground Cluster without backlogs are allowed to be “ sleeping ” for further power conserving

15. Power-Efficiency Clustering Method (2/2) Dynamic Transmission Range Control Protocol (DTRCP) Dynamically change the transmission range of each node Keep its neighbors nearly constant regardless of the node distribution Cluster Head Election Protocol (CHEP) Minimize the global energy usage of a network Distributes the traffic load to all the nodes

16. Power-Efficiency Clustering Method Dynamic Transmission Range Control Protocol (DTRCP) Transmission Range Expanse and Neighborhood Establishment Transmission Range Shrink and Neighborhood Denial

17. Dynamic Transmission Range Control Protocol (DTRCP)

18. Transmission Range Expanse and Neighborhood Establishment (1/2) Ni<Dl Ti Event: i Ti+ΔR

19. Transmission Range Expanse and Neighborhood Establishment (1/2) Ni<Dl Event: i Ti+ΔR Req i

20. Transmission Range Expanse and Neighborhood Establishment (1/2) Req i Ack j ij Event: Ni<Dl Event: Nj<Dh MTj I K NTj nodeStatus M L IREQ k update NTi nodeStatus A B J ACK

21. Transmission Range Expanse and Neighborhood Establishment (1/2) ACK i ij Event: Ni<Dl Event: Nj<Dh MTj I K NTj nodeStatus M L IACK k update NTi nodeStatus A B J ACK

22. Transmission Range Expanse and Neighborhood Establishment (2/2) Two sub-cases that need to be considered Node I is satisfied, and no more further Reqi are sent No one to successfully respond to i ’ s request until the maximum transmission range, MAXRANGE, is reached

23. Transmission Range Shrink and Neighborhood Denial Two situations to shrink A node i has Ni larger than Dl i has Ni larger than Dh Its distances to all neighbors are estimated and sorted in NTi Given an infinite large value-INF, to make a denial to all neighbors

24. Power-Efficiency Clustering Method Cluster Head Election Protocol (CHEP) Partitioning stage Choosing stage Hierarchy clustering stage

25. Cluster Head Election Protocol (CHEP) (1/5) Initial phase Partitioning stage: Every node i maintains a triplet: A unique identification ID(i) A cluster identification CID(i) to which i belongs Remaining battery power, Crp(i) The clustering method LEACH the coordinator eligibility rule in Span

26. Cluster Head Election Protocol (CHEP) (2/5) Choosing stage: All member send Crp(i) to its cluster head The cluster head chooses the node with the maximum power as the new cluster-head Broadcasts the decision to its members Hierarchy clustering stage: Construct a higher-level cluster Each node by default can directly communicate with each other with varying transmission range

27. Cluster Head Election Protocol (CHEP) (3/5) Re-Clustering Phase When a cluster cycle is over, a cluster-head switches its role back to a node with the most residual power

28. Cluster Head Election Protocol (CHEP) (4/5) Clustering method is suggested to work for static sensor networks Extensions to dynamic networks Nodes can change location Nodes can be removed Nodes can be added

29. Cluster Head Election Protocol (CHEP) (5/5) The topology is changed, the maintenance scheme is carried out The procedure of selecting new cluster- heads is followed The initial phase can still handle this case to produce new cluster-heads The suit environment is static or dynamic

30. Power Limit Constraint

31. Power Limit Constraint (1/8) The combining of the benefits of minimizing the power consumption in a path with that of maximizing residual power in a node

32. Power Limit Constraint (2/8) Radio Model Short distances the propagation loss is modeled as inversely proportional to d 2 Long distances the propagation loss is modeled as inversely proportional to d 4

33. Power Limit Constraint (3/8) To transmit a k-bit packet a distance d, the radio expends the following energy: the electronics energy before it is sent to the transmit amplifier the transmit amplifier to give a reasonable signal to noise ratio (SNR)

34. Power Limit Constraint (4/8) Redirect One or more intermediate nodes called “ redirectors ” can be elected to forward packets Inadvertently overusing

35. Power Limit Constraint (5/8) Firstly Decide whether an overhearing node can re-direct for an existing path or not Secondly The extended PECM utilizes bandwidth restriction to allow a redirected path

36. Power Limit Constraint (6/8) Source i transmits data to destination k through a redirector j restrict the area between two communicating nodes where a potential redirector can be selected from

37. Power Limit Constraint (7/8) Power-limit constraint δ is the inter/intra parameter. Two-layer redirection strategy Inter-cluster redirection Intra-cluster redirection

38. Power Limit Constraint (8/8)

39. Performance Evaluation

40. Performance Evaluation (1/6)

41. Performance Evaluation (2/6)

42. Performance Evaluation (3/6)

43. Performance Evaluation (4/6)

44. Performance Evaluation (5/6)

45. Performance Evaluation (6/6)

46. Conclusion Provide a re-clustering scheme and a power- limit constraint on redirection into cluster based power-efficiency sensor wireless networks Conventional clustering methods by requiring Highest energy node should be a cluster-head at different cycles of time A node with power higher than its source, to be a redirector