Wireless
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Principles and Practice


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To Fei’s family—Fang and Gloria ……
To Matt’s family ……



Contents
Preface .........................................................................................................xvii
Acknowledgments ..................................................................................... xxiii
Disclaimer ...................................................................................................xxv
Authors ......................................................................................................xxvii

PART I
1

Introduction ...........................................................................................3
1.1 B asics .................................................................................................3
1.2 M AC Layer........................................................................................9
1.3 R outing ...........................................................................................10

1.4 Other Communication Issues ..........................................................10
1.5 S ensor Localization..........................................................................12
1.6 C lock Synchronization ....................................................................13
1.7 P ower Management .........................................................................13
1.8 S pecial WSNs ..................................................................................14
1.8.1 Wireless Multimedia Sensor Networks ...............................14
1.8.2 Underwater Acoustic Sensor Networks ...............................16
1.9 WSN Applications...........................................................................18
Problems and Exercises...............................................................................22

PART II
2

BASICS

ENGINEERING DESIGN

Hardware—Sensor Mote Architecture and Design .............................27
2.1 Components of a Sensor Mote .........................................................27
2.1.1 S ensors................................................................................28
2.1.2 M icroprocessor ...................................................................30
2.1.3 M emory ..............................................................................35
2.1.4 R adios ................................................................................36
2.1.5 P ower Sources .....................................................................41
2.1.6 P eripheral Support ..............................................................43
vii


viii ◾


Contents

2.2

Put Everything Together ................................................................ 44
2.2.1 Typical Sensor Mote Architecture...................................... 44
2.2.1.1 Wireless Communication Requirements............ 44
2.2.1.2 K ey Issues ...........................................................45
2.2.1.3 Traditional Wireless Design............................... 46
2.2.1.4 Mote Example: Reno ..........................................47
2.3 Mica Mote Design ...........................................................................48
2.4 Cu stomized Mote—Spec ................................................................50
2.5 COTS Dust Systems .......................................................................52
2.5.1 Design Advice: Failures and Successes ................................53
2.6 T elos Mote .......................................................................................54
2.7 C argoNet.........................................................................................57
Problems and Exercises...............................................................................62

PART III
3

NETWORK PROTOCOL STACK

Medium Access Control in Wireless Sensor Networks .........................67
3.1 I ntroduction ....................................................................................67
3.1.1 Medium Access Control in Wireless Networks ...................68
3.1.2 MAC Design Is Challenging in WSNs ...............................68
3.1.2.1 R esource Constraints ..........................................68
3.1.2.2 Signal Loss in Wireless Channel .........................69
3.1.2.3 Collisions Occurring at the Receiver’s End .........70

3.1.2.4 Hidden Terminal and Exposed Terminal
Problems .............................................................70
3.2 Overview of Project IEEE 802.11 ....................................................72
3.2.1 Point Coordination Function .............................................73
3.2.2 Distributed Coordination Function ....................................74
3.3 C lassification of MAC Protocols ..................................................... 77
3.3.1 Contention-Based MAC Protocols .................................... 77
3.3.1.1 Sensor Medium Access Control ..........................78
3.3.1.2 Ti meout MAC....................................................83
3.3.2 Schedule-Based MAC Protocols .........................................88
3.3.2.1 T raffic Adaptive Medium Access Protocol ..........89
3.3.3 Hybrid and Event-Based MAC Protocols............................94
3.3.3.1 Sift Medium Access Control...............................94
3.3.3.2 Berkeley Medium Access Control .....................100
3.3.3.3 Zebra Medium Access Control .........................102
3.4 C onclusion ....................................................................................107
Problems and Exercises.............................................................................107


Contents

4

◾ ix

Routing in Wireless Sensor Networks ................................................109
4.1 I ntroduction ..................................................................................109
4.1.1 Limited Resources in WSNs ............................................. 110
4.1.2 F ault Tolerance ................................................................. 110
4.1.3 Data Reporting and Aggregation ...................................... 111

4.1.4 N ode Deployment ............................................................ 111
4.1.5 Scalability and Coverage................................................... 111
4.1.6 Network Dynamics and Heterogeneity ............................112
4.2 Layout for the Chapter ..................................................................112
4.3 C lassification of Routing Protocols in WSNs ................................113
4.3.1 Proactive and Reactive Routing ........................................113
4.3.2 Flat and Hierarchical Routing ..........................................113
4.4 Data-Centric Routing Protocols in WSNs ..................................... 114
4.4.1 Flooding and Gossiping.................................................... 115
4.4.1.1 I deal Dissemination .......................................... 117
4.4.2 Sensor Protocols for Information via Negotiation ............. 117
4.4.2.1 Design of SPIN ................................................ 118
4.4.2.2 D ifferent Types of SPIN ................................... 119
4.4.2.3 Evaluating SPIN Protocols ...............................120
4.4.3 D irected Diffusion............................................................122
4.4.3.1 N aming ............................................................123
4.4.3.2 Interest Propagation and Gradient
Establishment ...................................................123
4.4.3.3 Dat a Propagation..............................................125
4.4.3.4 R einforcement ..................................................126
4.4.3.5 Evaluating Directed Diffusion ..........................127
4.5 Hierarchical Routing Protocols in WSNs ......................................128
4.5.1 Low-Energy Adaptive Clustering Hierarchy Protocol .......129
4.5.1.1 P rotocol Design ................................................130
4.5.1.2 Setup Phase: Cluster Formation and
Cluster- Head Selection .....................................130
4.5.1.3 Steady State Phase ............................................131
4.5.1.4 L EACH-Centralized ........................................133
4.5.1.5 Evaluating LEACH Protocol ............................133
4.5.2 Thre shold-Sensitive Energy-Efficient Sensor

Network Protocol .............................................................134
4.5.2.1 Sensor Network Model in TEEN .....................134
4.5.2.2 Operation of TEEN Protocol ...........................134
4.5.2.3 Evaluating TEEN Protocol ...............................136
4.5.2.4 Adaptive Periodic Thre shold-Sensitive
Energy-Efficient Network Protocol ...................137


x

◾

Contents

4.6

Location-Based Routing Protocols in WSNs .................................138
4.6.1 Geographical and Energy-Aware Routing Protocol...........139
4.6.1.1 Phases of GEAR ...............................................139
4.6.1.2 Energy-Aware Neighbor Computation .............140
4.6.1.3 Recursive Geographic Forwarding ....................143
4.6.1.4 Evaluating GEAR Protocol...............................144
4.7 Multipath and QoS-Based Routing ............................................... 145
4.7.1 M ultipath Routing ........................................................... 145
4.7.2 QoS-Based Routing Protocols in WSNs ...........................147
4.8 C onclusion ....................................................................................148
Problems and Exercises.............................................................................148

5


Transport Layer in Wireless Sensor Networks ...................................151
5.1 I ntroduction .................................................................................. 152
5.2 Pump Slowly, Fetch Quickly ......................................................... 152
5.2.1 Why Does TCP Not Work Well in WSNs? ...................... 152
5.2.2 K ey Ideas ..........................................................................154
5.2.3 P rotocol Description ......................................................... 158
5.2.3.1 Pu mp Operation............................................... 159
5.2.3.2 F etch Operation ...............................................160
5.2.3.3 R eport Operation .............................................162
5.3 Another WSN Transport Protocol—ESRT ...................................163
5.3.1 Reliable Transport Problem ..............................................163
5.3.2 Relationship between Normalized Event Reliability
and Report Frequency ......................................................164
5.3.3 C ongestion Detection .......................................................170
5.4 E 2SRT: Enhanced ESRT Performance...........................................171
5.4.1 The Proposed Scheme—E2SRT ........................................173
5.5 CODA: Congestion Detection and Avoidance in Sensor
Networks .......................................................................................178
5.5.1 Open-Loop, Hop-to-Hop Backpressure............................182
5.5.2 C ongestion Detection .......................................................183
5.5.3 Listening to Channel Based on Sampling .........................183
5.6 STCP: A Generic Transport Layer Protocol for WSNs ..................185
5.6.1 Data Transmission Sequence in STCP .............................185
5.6.2 STCP Packet Formats.......................................................185
5.6.3 C ontinuous Flows.............................................................187
5.6.4 E vent-Driven Flows ..........................................................188
5.6.5 R eliability .........................................................................188
5.6.6 Congestion Detection and Avoidance ...............................188
5.6.7 Dat a-Centric Applications ................................................189



Contents

◾

xi

5.7

GARUDA: Achieving Effective Reliability
for Downstream Communication .................................................189
5.7.1 Challenges to the Downstream Reliability of WSNs ........190
5.7.1.1 E nvironment Constraints .................................190
5.7.1.2 Acknowledgment (ACK)/NACK Paradox ........190
5.7.1.3 R eliability Semantics ........................................190
5.7.2 GARUDA Design Basics .................................................. 191
5.7.2.1 Loss Recovery Servers: Core ............................. 191
5.7.2.2 Loss Recovery Process.......................................192
5.7.3 G ARUDA Framework ......................................................193
5.7.3.1 Core Construction Procedure ...........................194
5.7.3.2 Two-Phase Loss Recovery .................................195
Problems and Exercises.............................................................................196

PART IV
6

COMPUTER SCIENCE PRINCIPLES

Operating System in Sensors ..............................................................201
6.1 Ti nyOS .........................................................................................201

6.1.1 O verview ..........................................................................202
6.1.2 C omponent Model ...........................................................203
6.1.3 Execution Model and Concurrency ................................. 206
6.1.4 A ctive Messages ............................................................... 208
6.1.5 I mplementation Status ..................................................... 208
6.1.6 M ain Features.................................................................. 208
6.1.7 L ow-Power Optimizations ................................................209
6.2 LA-TinyOS—A Locality-Aware Operating System
for WSNs ...............................................................................209
6.2.1 Change Timer to Respond to Temporal and Spatial
Locality ............................................................................211
6.2.2 M ultiple-Level Scheduler ..................................................213
6.2.3 LA-TinyOS Code Structure.............................................. 214
6.3 SOS ............................................................................................... 215
6.3.1 M odules............................................................................216
6.3.1.1 M odule Structure .............................................216
6.3.1.2 M odule Interaction ........................................... 217
6.3.1.3 Module Insertion and Removal ........................ 217
6.3.2 D ynamic Memory ............................................................ 219
6.4 R ETOS ......................................................................................... 219
6.4.1 Application Code Checking ............................................. 219
6.4.2 M ultithreading System .....................................................221
6.4.3 Loadable Kernel Module ................................................. 222
Problems and Exercises.............................................................................223


xii

◾


Contents

7

Middleware Design in Wireless Sensor Networks..............................225
7.1 I ntroduction ..................................................................................225
7.2 Reference Model of WSN Middleware ..........................................227
7.2.1 M odel Overview ...............................................................227
7.3 Middleware Example: Agilla ........................................................ 228
7.4 Middleware for Data Acquisition: Mires .......................................231
7.5 Data Storage: DSWare...................................................................233
7.6 WSN Runtime Support Example: Mate ....................................... 234
7.7 QoS Support Example: MiLAN ....................................................235
Problems and Exercises.............................................................................236

8

Sensor Data Management...................................................................237
8.1 Sensor Data Cleaning ....................................................................237
8.1.1 B ackground ......................................................................237
8.1.2 G eneral Model..................................................................239
8.1.3 Reducing the Uncertainty ................................................241
8.2 TinyDB: An Acquisitional Query-Processing System
for Sensor Networks ......................................................................243
8.2.1 Dat a Model ......................................................................245
8.2.2 Basic Language Features ...................................................245
8.2.3 E vent-Based Queries ........................................................ 246
8.2.4 Other Queries Defined in TinyDB .................................. 246
8.2.5 Power-Based Query Optimization ....................................247
8.2.6 Summary of TinyDB Strategies ........................................249

8.3 Data Aggregation: AIDA ...............................................................249
8.4 Sensor Data Storage: Tiered Storage ARchitecture (TSAR)...........253
8.5 Multi-Resolution Data Processing .................................................256
Problems and Exercises.............................................................................257

PART V
9

ADVANCED TOPICS

Sensor Localization ............................................................................261
9.1 I ntroduction ..................................................................................261
9.2 Elements of Localization ...............................................................262
9.2.1 Received Signal Strength Indication .................................262
9.2.2 Time of Arrival ................................................................ 264
9.2.3 Ti me Difference of Arrival............................................... 264
9.2.4 Angle of Arrival ............................................................... 266
9.2.5 T riangulation................................................................... 266
9.2.6 T rilateration..................................................................... 266
9.2.7 M ultilateration .................................................................267
9.3 Using Mobile Robots for Sensor Localization ............................... 268
9.3.1 Delay-Tolerant Sensor Networks...................................... 268


Contents

◾ xiii

9.3.1.1 System Dynamic Model ...................................269
9.3.1.2 RSSI Measurement Model ................................271

9.4 Sensor Localization with Multidimensional Scaling ......................274
9.4.1 Classical Multidimensional Scaling ..................................274
9.4.2 Iterative Multidimensional Scaling ...................................275
9.4.2.1 Hop Distance and Ranging Estimation ............276
9.4.2.2 Aligning Relative Location to Physical
Location ...........................................................276
9.4.2.3 Distributed Physical Location Estimation ........278
9.5 Localization in Wireless Sensor Networks .................................... 280
9.5.1 The Monte Carlo Method................................................ 280
9.5.2 A lgorithm (1) ....................................................................281
9.5.3 A lgorithm (2) .................................................................. 284
9.6 GPS-Free Node Localization in Mobile WSN ...............................285
9.7 A High-Accuracy, Low-Cost Localization System for WSN ..........290
9.8 LOCALE: Collaborative Localization Estimation for Sparse
Mobile Sensor Networks ...............................................................295
9.8.1 Collaborative Location Estimation ...................................296
9.8.2 Location in LOCALE ......................................................297
9.8.3 L ocal Phase.......................................................................297
9.8.4 T ransform Phase ...............................................................299
9.8.5 U pdate Phase ....................................................................301
9.9 On the Security of WSN Localization ...........................................303
9.9.1 S eRLoc .............................................................................303
9.9.2 B eacon Suite .................................................................... 304
9.9.3 Attack-Resistant Location Estimation ............................. 304
9.9.4 Robust Statistical Methods ...............................................305
Problems and Exercises.............................................................................305

10 Time Synchronization in Wireless Sensor Networks .........................307

10.1 I ntroduction ..................................................................................307

10.2 Synchronization in General Networks (Non-WSN) ...................... 311
10.2.1 Remote Clock Reading ..................................................... 311
10.2.2 O ffset Delay Estimation Method...................................... 311
10.3 Clock Synchronization in WSNs ................................................... 314
10.4 Evaluation of Synchronization Performance .................................. 317
10.4.1 P recision ........................................................................... 317
10.4.2 P rotocol Overhead ............................................................ 318
10.4.3 C onvergence Time............................................................ 318
10.4.4 E nergy Efficiency .............................................................. 318
10.4.5 S calability ......................................................................... 318
10.4.6 R obustness........................................................................ 318
10.5 Examples of WSN Synchronization Protocols ............................... 319


xiv

◾

Contents

10.5.1 Reference Broadcast Synchronization ............................... 319
10.5.2 Ti me-Diff usion Synchronization Protocol ........................321
10.5.3 Probabilistic Clock Synchronization .................................324
Problems and Exercises.............................................................................325

11 Security and Privacy in Wireless Sensor Networks ............................327

11.1 I ntroduction ..................................................................................327
11.1.1 General Attack Taxonomy ................................................327
11.1.2 Attacks on Physical Sensor Motes .....................................328

11.1.3 Attacks on WSN Communication Stack ..........................330
11.1.3.1 P hysical Layer ...................................................330
11.1.3.2 L ink Layer ........................................................330
11.1.3.3 R outing Layer ...................................................331
11.1.3.4 T ransport Layer ................................................335
11.1.3.5 T raffic Analysis Attacks ....................................335
11.2 Attack and Countermeasure Example: Wormhole Attack..............336
11.2.1 Wormhole Defense Scheme—LITEWORP .....................336
11.2.1.1 Building Neighbor Lists .................................. 340
11.3 WSN Security Example: Blom-Based Approach ........................... 344
11.4 B roadcast Authentication: μTESLA ..............................................347
11.4.1 μTESLA’s Detailed Description........................................350
11.5 Practical Security Schemes for “Motes” .........................................352
11.5.1 Ti nySec ............................................................................352
11.5.2 MiniSec: A Secure Sensor Network Communication
Architecture ......................................................................353
11.6 Special Case: Secure Time Synchronization in WSNs ...................354
Problems and Exercises.............................................................................359

PART VI

SPECIAL WIRELESS SENSOR NETWORKS

12 Wireless Sensor and Actor Networks..................................................363
12.1 I ntroduction ..................................................................................363
12.2 Sensor–Actor Coordination Problem ............................................ 366
12.2.1 Network and Energy Model .............................................367
12.2.2 I LP Algorithm ..................................................................367
12.2.3 Sensor–Actor Coordination: Distributed Protocol ............370
12.2.4 Overview of DEPR ...........................................................371

12.3 Hierarchical Sensor–Actor Coordination Mechanism ...................373
12.3.1 Hierarchical WSAN Coordination Architecture ..............373
12.3.2 “Sensor–Sensor” Coordination Level—Use Clusters ........374
12.3.3 “Sensor–Actor” Coordination Level .................................376
12.3.4 “Actor–Actor” Coordination Level ...................................377
Problems and Exercises.............................................................................378


Contents

◾

xv

13 Underwater Sensor Networks .............................................................379

13.1 I ntroduction ..................................................................................379
13.1.1 Underwater WSN Applications ........................................379
13.1.2 D ifferences between USNs and Terrestrial Sensor
Networks ..........................................................................380
13.1.3 N etwork Topology............................................................381
13.1.4 Acoustic Signals Propagation ............................................382
13.1.5 U nderwater Sensors ..........................................................383
13.2 USN Protocol Stack.......................................................................384
13.2.1 P hysical Layer ...................................................................384
13.2.2 Data Link Layer ...............................................................385
13.2.3 Network Layer (Routing Layer) ........................................386
13.2.4 T ransport Layer ................................................................386
13.3 MAC Design Example ..................................................................387
13.4 Routing Design Example: Vector-Based

Forwarding Protocol ............................................................. 390
13.5 Hardware Prototype Design ..........................................................393
13.5.1 Ha rdware Design..............................................................394
13.5.2 S oftware Design ...............................................................396
13.5.3 S ystem Testing ..................................................................396
Problems and Exercises.............................................................................398

14 Video Sensor Networks ......................................................................399

14.1 I ntroduction ..................................................................................399
14.2 P anoptes ........................................................................................401
14.2.1 V ideo Capture ..................................................................402
14.2.2 V ideo Compression ..........................................................402
14.2.3 Dat a Filtering ...................................................................402
14.2.4 Dat a Buffering ..................................................................402
14.3 C yclops ..........................................................................................403
14.4 VSN Calibration ...........................................................................405
14.4.1 Determining the Degree of Overlap .................................407
14.4.2 E stimating k-overlap .........................................................407
14.5 S ensEye ........................................................................................ 408
Problems and Exercises.............................................................................412

PART VII

MISCELLANEOUS TOPICS

15 WSN Energy Model............................................................................415
15.1 Basic WSN Energy Model ............................................................. 415
15.2 Simulation-Based Energy Modeling ..............................................418
15.3 B attery-Aware Routing ..................................................................425

Problems and Exercises.............................................................................429


xvi

◾

Contents

16 Sensor Network Simulators ................................................................431
16.1 Gl oMoSim.....................................................................................431
16.2 S ensorSim ......................................................................................432
16.3 T OSSIM ...................................................................................... 434
16.4 P owerTOSSIM ..............................................................................437
16.4.1 P owerTOSSIM Architecture .............................................437
16.4.2 C omponent Instrumentation ............................................439
16.4.3 C PU Profiling...................................................................439
16.4.4 P owerState Module .......................................................... 440
16.4.5 A nalysis Tools .................................................................. 440
Problems and Exercises.............................................................................441

PART VIII

CASE STUDIES

17 Case Study 1: Tele-Healthcare ........................................................... 445

17.1 I ntroduction ..................................................................................445
17.2 MASN Hardware Design ..............................................................447
17.2.1 ECG Sensors and RF Communication Hardware ............447

17.3 Reliable MASN Communication Protocols ...................................450
17.3.1 Enhanced Cluster-Based MASN Data Transmission ........450
17.3.2 MASN Routing Performance ...........................................453
17.4 MASN Software Design................................................................455
17.4.1 ECG Sensor Mote Wireless Communication Software.....455
17.5 Integration of RFID and Wearable Sensors ...................................457
Problems and Exercises.............................................................................462

18 Case Study 2: Light Control ...............................................................465
18.1 I ntroduction ..................................................................................465
18.2 I llumimote’s Sensors ..................................................................... 468
18.3 S ystem Architecture .......................................................................469
18.4 C alibration ....................................................................................469
18.5 S ystem Evaluation .........................................................................470
Problems and Exercises.............................................................................472

References ...................................................................................................475
Index ...........................................................................................................495


Preface
Wireless s ensor n etworks ( WSNs) a re o ne o f t he h ottest to pics o f re search i n
today’s era of information explosion. The latest advances in science and engineering
have paved the way for employing the low-power, low-cost WSN, which provides
a high order of spatial and effective resolution for an ever-increasing number of
applications, such as infrastructure protection and security, surveillance, healthcare, habitat/environment monitoring, food safety, and smart energy. A lthough
the u se of WSNs h as m any a dvantages over t raditional networking te chniques
and sensing methods in the aforementioned applications, it also poses many challenging issues and optimization problems in the design of network architectures,
protocols, a nd a lgorithms. To re solve t hese c hallenges de spite c onstraints on
available energy, bandwidth, memory space and computing power, high rates of

node f ailure a nd d ata l oss, a dverse c ommunication en vironments, a nd u nique
application re quirements, si gnifi cant efforts have been made in the academia
and industry.
Although some books on sensor networks have been published recently, most
(if n ot a ll) o f t hem a re n ot su itable to b e u sed a s te xtbooks d ue to t he l imited
number of topics covered or to the nature of editorial collections. This textbook
attempts to c omprehensively discuss all the major technologies, standards, topics,
and developments in sensor networks. It covers almost all aspects that readers need
to know to enter this burgeoning field, including hardware design, medium access
control, routing schemes, transport protocols, OS support, middleware, data management, localization, synchronization, security, actuator/underwater/video sensor
networking, power control, and sensor simulations.
This textbook makes complicated concepts easy to u nderstand through interesting examples and WSN applications. In addition, it has exercises, assignments,
and detailed case studies that help readers understand the contents and then apply
their knowledge in designing their own applications or for solving real-world problems. We h ave a lso i ncluded some practical s ensor network de sign c ases suc h a s
medical applications.

xvii


xviii ◾

Preface

Targeted Audiences
This book is ideal for senior college students or first-year graduate students who are
majoring in computer engineering, electrical engineering, or computer science. It is
also an excellent reference book for sensor network designers, researchers, and engineers who wish to f ully exploit WSN te chnology, and for government employees
who wish to use WSNs to enhance homeland security.

Scope of This Book

Because we t arget b oth en gineering a nd sci ence s tudents, we h ave c overed b oth
hardware and software topics in this textbook. This boo k, wh ich c onsists o f 18
chapters, is organized in the following manner:

Chapter 1. Introduction (WSN overview; basic network
concepts)
Computer
engineering
knowledge

Chapter 2. Hardware (micro-sensors with
microcontrollers and radio)

Network protocol
stack

Chapter 3. MAC layer (neighborhood wireless
transmission)
Chapter 4. Routing layer (find an optimal source-to-end
path)
Chapter 5. Transport layer (loss recovery, congestion
control)

Computer science
knowledge

Chapter 6. Operating system (such as TinyOS)
Chapter 7. Middleware (hide networking details for
programmers)
Chapter 8. Sensor data management


Advanced WSN
topics

Chapter 9. Localization (also called calibration; very
useful)
Chapter 10. Clock synchronization (correct clock drifts
in sensors)
Chapter 11. Security (countermeasure WSN attacks)


Preface ◾

xix

(continued)
Special sensor
networks

Chapter 12. Wireless actor and sensor networks
(with mobile actors)
Chapter 13. Underwater sensor networks (using
acoustic; not RF)
Chapter 14. Video sensor networks

Miscellaneous

Chapter 15. Energy models and low-energy design
Chapter 16. WSN simulators


Case studies

Chapter 17. WSN for tele-healthcare applications
Chapter 18. WSN for light control

What Can Be Covered in a Course
For a One -Semester (15 Weeks) C ourse: The fo llowing t able i s o ur su ggested
time allocation plan among different topics. Instructors should adjust their teaching plan based on students’ feedback and learning practices.
Time Length

Teaching Topics

Chapters

2 weeks

WSN basics; sensor hardware (for computer
science major, the hardware part can be
shortened)

Chapters 1
and 2

2 weeks

MAC layer (teach at least two MAC schemes,
emphasizing “energy-saving” design)

Chapter 3


2.5 weeks

Routing layer (teach proactive/reactive
routing schemes, emphasizing “scalable”
design)

Chapter 4

1.5 weeks

Transport layer (teach both “reliable end-toend transmission” and “congestion control”)

Chapter 5

1 week

Operating system; middleware (for computer
science major, 2 weeks may be used)

Chapters 6
and 7

1 week

Sensor data management (for computer
science major, 2 weeks may be used)

Chapter 8

1 week


Sensor localization; time synchronization (for
PhD/MS students, 2–3 weeks may be used)

Chapters 9
and 10
(continued)


xx ◾

Preface

(continued)
Time Length

Teaching Topics

Chapters

1 week

WSN security (Teach μTESLA, Key predistribution)

Chapter 11

1.5 weeks

Special sensor networks (especially
underwater WSN)


Chapters 12
through 14

0.5 week

Energy models; WSN simulators

Chapters 15
and 16

1 week

Case studies

Chapters 17
and 18

Total: 15
weeks

In each chapter, teach both math principles
and concrete design cases. Leave some
topics for after-class reading assignments.

Note that some time should also be allocated for class labs.
For a One-Quarter (10 Weeks) Course:
Time Length

Teaching Topics


Chapters

1.5 weeks

WSN basics; sensor hardware

Chapters 1 and 2

1 week

MAC layer (emphasizing “energy-saving”
design)

Chapter 3

1.5 weeks

Routing layer (teach proactive/reactive
routing schemes; emphasizing “scalable”
design)

Chapter 4

1 week

Transport layer (teach both “reliable
end-to-end transmission” and “congestion
control”)


Chapter 5

0.5 week

Operating system; middleware (for
computer science major, 1.5 weeks may be
used)

Chapters 6 and 7

0.5 week

Sensor data management (for computer
science major, 1.5 weeks may be used)

Chapter 8

1 week

Sensor localization; time synchronization
(for PhD/MS students, 2–3 weeks may be
used)

Chapters
9 and 10


Preface ◾

xxi


(continued)
Time Length

Teaching Topics

Chapters

0.5 week

WSN security (Teach μTESLA, Key predistribution)

Chapter 11

1 week

Special sensor networks (especially
underwater WSN)

Chapters 12
through 14

0.5 week

Energy models; WSN simulators

Chapters
15 and 16

1 week


Case studies

Chapters 17
and 18

Total: 10
weeks

In each chapter, teach both math principles
and concrete design cases. Leave some
topics for after-class reading assignments.

For c omputer en gineering m ajors, C hapter 2 ( sensor h ardware) i s i mportant.
This chapter may be allocated more time as it would require a detailed study. For
computer science majors, Chapters 6 through 8 (OS, data management) should be
covered in more details.
Some chapters, such as Chapters 8 t hrough 10 (localization, synchronization,
and security), may be assigned to PhD/MS students as term paper topics (i.e., the
students a re re quired to e xplore t his to pic i n m ore de tail a nd sub mit a re search
paper based on their investigations). Chapters 17 and 18 could be used as projects
for senior students.
While teaching, the use of survey-like PowerPoint® slides is not recommended in
class as this book covers WSN topics in detail. Instructors should select good design
examples to elaborate certain concepts. For instance, when studying MAC layers, at
least one of the MAC schemes (such as S-MAC) should be taught in detail.
Math p rinciples a re e xtremely i mportant to WSN de sign. Therefore, i f a ny
chapter has some good math models, they should be studied carefully. The se math
principles should especially be emphasized for PhD/MS students.
MATLAB® i s a re gistered t rademark o f The M athWorks, I nc. F or p roduct

information, please contact:
The MathWorks, Inc.
3 Apple Hill Drive
Natick, MA 01760-2098 USA
Tel: 508 647 7000
Fax: 508-647-7001
E-mail:
Web: www.mathworks.com



Acknowledgments
Dr. Xiaojun Cao has contributed about one fifth of the contents of this book, and
the remaining text has been written by Dr. Fei Hu. We wish to express our gratitude
to all those who have helped us during the preparation of this book. Students in the
Department of Electrical and Computer Engineering at the University of Alabama,
Tuscaloosa, have helped to edit some figures and math equations. They have also
helped to edit some of the content. We are grateful to Rahul Mallampati for helping
us revise the content, edit some figures, and format the text in Microsoft Word®.
Thanks a lso to B arnali Chakrabarty a nd t he staff at A uerbach Publications who
have provided us continuous support during the writing effort.
A final note: Much of the content and concepts of the textbook are based on
existing research efforts from the literature that we cannot list here specifically.
We would like to particularly express our appreciation to those authors who have
published excellent materials on WSNs.

xxiii