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

Shi Bai, Weiyi Zhang, Guoliang Xue, Jian Tang, and Chonggang WangUniversity of Minnesota, AT&T Lab, Arizona State University, Syracuse

University, NEC Lab2012 IEEE INFOCOM

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1. Introduction 2. Algorithm

◦ 2.1 Definition◦ 2.2 Problem statement◦ 2.3 DEAR Algorithm

3. Experiment 4. Conclusion

Outline

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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

Introduction

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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

Definition (1)

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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

Definition (2)

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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

Transmission delay(1)

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◦ 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

Transmission delay(2)

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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

Problem Statement

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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

DEAR problem(1)

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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%

DEAR problem(2)

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IDEAR

Algorithm 1

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Linear Program solution

Restricted Maximum Flow scheme

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ODEAR problem◦ Optimization problem

SPDEAR problem◦ (1+α) approximation algorithm

Algorithm 1

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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.

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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])

Graph Transformation(2)

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Fully Polynomial Time Approximation Scheme for SPDEAR◦ Scaling and rounding technique◦ dΘ= ⌊d(e)*Θ⌋ + 1

Algorithm 2

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Approximation algorithm for ODEAR◦ dmin ≥ 0

Algorithm 3

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Efficient Heuristic for DEAR◦ Round the propagation delay of each link◦ dmin and dmax

Algorithm 4

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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]

Result (1)

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Performance of different number of nodes

Results (2)

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Performance of different reliability requirements

Results (3)

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Performance of different packet sizes

Results (4)

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Transmission delay in multipath routing◦ The previous work ignored

Delay-bounded Energy-constrained Adaptive Routing (DEAR)◦ Adaptive multipath routing◦ Energy constraint◦ Differential delay

Conclusion

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Thank you.

Q&A