DEAR: Delay-bounded Energy-constrained Adaptive Routing in Wireless Sensor Networks

1. DEAR: Delay-bounded Energy-constrained Adaptive Routing in Wireless Sensor Networks Shi Bai, Weiyi Zhang, GuoliangXue, Jian Tang, and Chonggang Wang University of Minnesota, AT&T Lab, Arizona State University, Syracuse University, NEC Lab 2012 IEEE INFOCOM

2. Outline • 1. Introduction • 2. Algorithm • 2.1 Definition • 2.2 Problem statement • 2.3 DEAR Algorithm • 3. Experiment • 4. Conclusion

3. Introduction • Wireless Sensor Networks • Key Issue: Energy Consumption • Delay-bounded Energy-constrained Adaptive Routing (DEAR) Problem • Adaptive reliability • Splitting the traffic over multiple paths • Differential delay • Increased memory and buffer overflow • Deliverable energy constraints • Energy consumption of transmitting packet

4. Definition (1) • Def 1. Packet Allocation • P is a set of s-BS paths. • The aggregated packet of link e is the sum of the packet allocations on link e of the paths in P: • q(e) = ƩL(p) • Def 2. Differential delay • dh => the highest path delay • dl => the lowest path delay • => Dp= dh – dl

5. Definition (2) • Def 3. Energy Consumption • Transmitting energy consumption • E = w*q • q => packet size transmitted on link • w => Energy consumption of transmitting 1 bit • W=[C*(2^b-1)+F]*(1/b) • C => the quality of transmission and noise power • F => the power consumption of electronic circuitry • Def 4. Latency/Delay • Queuing delay • The time waiting at output link for transmission • Transmission delay • The amount of time required to push all of the packet bits into the transmission media • Propagation delay • The time takes for the head of the signal to travel from the sender to the receiver

6. Transmission delay(1) • Transmission delay • Ignored transmission and queuing delay • Without considering the transmission delay • Allocate of packets have no impact on delivery of packets • Path:p1=(A,B,BS), p2=(A,C,BS), p3=(A,BS) • Path delay: d(p1)=2, d(p2)=3, d(p3)=2 • Ex a) packet split => p1=10, p3 = 2 • Ex b) packet split => p1= 6, p3 = 6 • Path delay are the same • Differential delay • d(p1)-d(p3) = 2 – 2 = 0

7. Transmission delay(2) • Considering the transmission delay • Allocations of packets on multiple paths will have impact on path delays • Path delay • d(p1) = Ʃd(e) + ƩƬ(v) • Ex a) d(p1) = 2 + (10 pk/(2 pk/s) + 10/2) = 12, d(p3) = 2 + (2/4) = 2.5 • Ex b) d(p1) = 2 +(6/2 + 6/2) = 8, d(p3) = 2 + (6/4) = 3.5 • Path delay are different • Ex a) Differential delay is 9.5=(12 - 2.5) • Ex b) Differential delay is 4.5

8. Problem Statement • DEAR(Delay-bounded Energy constrained Adaptive Routing) • Seek set of paths P that can provide the following • Delay bounded • Energy constrained • Adaptive reliability • Graph G=(V, E, b, d, w, β) • V represents the set of sensor nodes and BS. • E represents the set of links. • b represents bandwidth • d represents the delay of the path p • w represents transmission energy consumption • β represents the residual energy of sensor v

9. DEAR problem(1) • Delay Bounded • Any path p in P must satisfy the differential delay constraint: dmin ≤ d(p) ≤ dmax • Energy Constrained • The energy consumption of transmitting packet for each sensor i cannot exceed its residual energy level β(i) • Adaptive reliability • The size of aggregated packet of all paths in P is no less than Q : q(P) ≥ Q • Route the data such that any single link failure does no affect more than x% of the total packets

10. DEAR problem(2) • Feasible and infeasible solution by Adaptive reliability and delay constraint • Ex c) 2,2,8 • In case 8 packet drop => 67% • Ex d) 6,4,2 • In case delay is 8 over between 4 and 5 • Ex e) 2,10 • In case 10 packet drop => over 70%

11. Algorithm 1 • IDEAR

12. Restricted Maximum Flow scheme • Linear Program solution

13. Algorithm 1 • ODEAR problem • Optimization problem • SPDEAR problem • (1+α) approximation algorithm

14. Graph Transformation(1) • Each u[t] means that node u can transmit packet at time t. • This bandwidth ensures that the packets sent by u at time i can not exceed b(e). • This ensures that only the packet, which arrive at BS no earlier than dmin and no later than dmax.

15. Graph Transformation(2) • Requirement Condition • Packet Demand: 12 Packet • Reliability requirement x% = 70% • Delay requirement: dmin = 2 and dmax = 5 • Maximum flow by IDEAR • P1=(A[0],B[2],BS[4],BS[5]) • P2=(A[0],C[3],BS[5]) • P3=(A[0],BS[3],BS[4],BS[5]) • P4=(A[0],A[1],BS[4],BS[5])

16. Algorithm 2 • Fully Polynomial Time Approximation Scheme for SPDEAR • Scaling and rounding technique • dΘ= ⌊d(e)*Θ⌋ + 1

17. Algorithm 3 • Approximation algorithm for ODEAR • dmin ≥ 0

18. Algorithm 4 • Efficient Heuristic for DEAR • Round the propagation delay of each link • dmin and dmax

19. Result (1) • Network topologies in an 100 * 100 sq • The power of Sensor node was randomly distributed in [16, 20] • Bandwidth, propagation delay and transmission energy consumption of each communication link was randomly distributed in [6,10], [1,5], [1,3]

20. Results (2) • Performance of different number of nodes

21. Results (3) • Performance of different reliability requirements

22. Results (4) • Performance of different packet sizes

23. Conclusion • Transmission delay in multipath routing • The previous work ignored • Delay-bounded Energy-constrained Adaptive Routing (DEAR) • Adaptive multipath routing • Energy constraint • Differential delay

24. Q&A • Thank you.