Ultra-Low Energy Wireless Sensor Networks in Practice

Timo D. Hämäläinen is Professor and Institute Vice President at Tampere University of Technology, Finland. Timo acted as a senior research scientist and project manager at TUT from 1997-2001. In 2001 he was nominated full professor at TUT/Institute of Digital and Computer Systems. He heads the DACI research group that focuses on three main lines: wireless local area networking and wireless sensor networks, high-performance DSP/HW based video encoding, and interconnection networks with design flow tools for heterogeneous SoC platforms. He has published over 30 refereed international journals and over 150 conference publications. Marko Hännikäinen is Senior Research Scientist and Mauri Kuorilehto, Mikko Kohvakka, Jukka Suhonen, Panu Hämäläinen are all Research Scientists at Tampere University of Technology, Finland.

Preface xiii

List of Abbreviations xv

PART I INTRODUCTION 1

1 Introduction 3

1.1 Overview of Wireless Technologies 3

1.2 TUTWSN 5

1.3 Contents of the Book 6

PART II DESIGN SPACE OF WSNS 7

2 WSN Properties 9

2.1 Characteristics of WSNs 9

2.2 WSN Applications 11

2.2.1 Commercial WSNs 12

2.2.2 Research WSNs 14

2.3 Requirements for WSNs 16

3 Standards and Proposals 19

3.1 Standards 19

3.1.1 IEEE 1451 Standard 19

3.1.2 IEEE 802.15 Standard 21

3.2 Variations of Standards 28

3.2.1 Wibree 28

3.2.2 Z-Wave 28

3.2.3 MiWi 28

4 Sensor Node Platforms 29

4.1 Platform Components 29

4.1.1 Communication Subsystem 30

4.1.2 Computing Subsystem 33

4.1.3 Sensing Subsystem 33

4.1.4 Power Subsystem 34

4.2 Existing Platforms 36

4.3 TUTWSN Platforms 39

4.3.1 Temperature-sensing Platform 39

4.3.2 SoC Node Prototype 43

4.3.3 Ethernet Gateway Prototype 44

4.4 Antenna Design 46

4.4.1 Antenna Design Flow 46

4.4.2 Planar Antenna Types 48

4.4.3 Trade-Offs in Antenna Design 49

5 Design of WSNs 51

5.1 Design Dimensions 51

5.2 WSN Design Flow 54

5.3 Related Research on WSN Design 56

5.3.1 WSN Design Methodologies 56

5.4 WSN Evaluation Methods 60

5.5 WSN Evaluation Tools 61

5.5.1 Networking Oriented Simulators for WSN 61

5.5.2 Sensor Node Simulators 62

5.5.3 Analysis of Evaluation Tools 63

PART III WSN PROTOCOL STACK 67

6 Protocol Stack Overview 69

6.1 Outline of WSN Stack 69

6.1.1 Physical Layer 70

6.1.2 Data Link Layer 71

6.1.3 Network Layer 71

6.1.4 Transport Layer 71

6.1.5 Application Layer 72

7 MAC Protocols 73

7.1 Requirements 73

7.2 General MAC Approaches 75

7.2.1 Contention Protocols 75

7.2.2 Contention-free Protocols 77

7.2.3 Multichannel Protocols 78

7.3 WSN MAC Protocols 80

7.3.1 Synchronized Low Duty-cycle Protocols 80

7.3.2 Unsynchronized Low Duty-cycle Protocols 85

7.3.3 Wake-up Radio Protocols 87

7.3.4 Summary 88

8 Routing Protocols 91

8.1 Requirements 91

8.2 Classifications 92

8.3 Operation Principles 93

8.3.1 Nodecentric Routing 93

8.3.2 Data-centric Routing 94

8.3.3 Location-based Routing 95

8.3.4 Multipath Routing 97

8.3.5 Negotiation-based Routing 97

8.3.6 Query-based Routing 98

8.3.7 Cost Field-based Routing 99

8.4 Summary 101

9 Middleware and Application Layer 103

9.1 Motivation and Requirements 103

9.2 WSN Middleware Approaches 105

9.3 WSN Middleware Proposals 106

9.3.1 Interfaces 106

9.3.2 Virtual Machines 107

9.3.3 Database Middlewares 107

9.3.4 Mobile Agent Middlewares 108

9.3.5 Application-driven Middlewares 108

9.3.6 Programming Abstractions 109

9.3.7 WSN Middleware Analysis 110

10 Operating Systems 115

10.1 Motivation and Requirements 115

10.1.1 OS Services and Requirements 116

10.1.2 Implementation Approaches 117

10.2 Existing OSs 119

10.2.1 Event-handler OSs 120

10.2.2 Preemptive Multithreading OSs 121

10.2.3 Analysis 121

11 QoS Issues in WSN 125

11.1 Traditional QoS 125

11.2 Unique Requirements in WSNs 125

11.3 Parameters Defining WSN QoS 126

11.4 QoS Support in Protocol Layers 128

11.4.1 Application Layer 128

11.4.2 Transport Layer 128

11.4.3 Network Layer 129

11.4.4 Data Link Layer 130

11.4.5 Physical Layer 131

11.5 Summary 131

12 Security in WSNs 133

12.1 WSN Security Threats and Countermeasures 133

12.1.1 Passive Attacks 134

12.1.2 Active Attacks 134

12.2 Security Architectures for WSNs 135

12.2.1 TinySec 135

12.2.2 SPINS 136

12.2.3 IEEE 802.15.4 Security 136

12.2.4 ZigBee Security 137

12.2.5 Bluetooth Security 139

12.3 Key Distribution in WSNs 140

12.3.1 Public-key Cryptography 140

12.3.2 Pre-distributed Keys 140

12.3.3 Centralized Key Distribution 141

12.4 Summary of WSN Security Considerations 142

PART IV TUTWSN 143

13 TUTWSN MAC Protocol 145

13.1 Network Topology 145

13.2 Channel Access 147

13.3 Frequency Division 149

13.4 Advanced Mobility Support 152

13.4.1 Proactive Distribution of Neighbor Information 153

13.4.2 Neighbor-discovery Algorithm 154

13.4.3 Measured Performance of ENDP Protocol 158

13.5 Advanced Support for Bursty Traffic 159

13.5.1 Slot Reservations within a Superframe 160

13.5.2 On-demand Slot Reservation 161

13.5.3 Traffic-adaptive Slot Reservation 161

13.5.4 Performance Analysis 162

13.6 TUTWSN MAC Optimization 165

13.6.1 Reducing Radio Requirements 165

13.6.2 Network Beacon Rate Optimization 170

13.7 TUTWSN MAC Implementation 179

13.8 Measured Performance of TUTWSN MAC 180

14 TUTWSN Routing Protocol 183

14.1 Design and Implementation 183

14.2 Related Work 183

14.3 Cost-Aware Routing 184

14.3.1 Sink-initiated Route Establishment 185

14.3.2 Node-initiated Route Discovery 185

14.3.3 Traffic Classification 186

14.4 Implementation 187

14.4.1 Protocol Architecture 187

14.4.2 Implementation on TUTWSN MAC 188

14.5 Measurement Results 188

14.5.1 Network Parameter Configuration 189

14.5.2 Network Build-up Time 189

14.5.3 Distribution of Traffic 190

14.5.4 End-to-end Delays 192

15 TUTWSN API 193

15.1 Design of TUTWSN API 194

15.1.1 Gateway API 194

15.1.2 Node API 196

15.2 TUTWSN API Implementation 197

15.2.1 Gateway API 198

15.2.2 Node API 198

15.3 TUTWSN API Evaluation 200

15.3.1 Ease of Use 200

15.3.2 Resource Consumption 200

15.3.3 Operational Performance 201

16 TUTWSN SensorOS 203

16.1 SensorOS Design 203

16.1.1 SensorOS Architecture 204

16.1.2 OS Components 204

16.2 SensorOS Implementation 206

16.2.1 HAL Implementation 206

16.2.2 Component Implementation 207

16.3 SensorOS Performance Evaluation 210

16.3.1 Resource Usage 210

16.3.2 Context Switch Performance 210

16.4 Lightweight Kernel Configuration 211

16.4.1 Lightweight OS Architecture and Implementation 211

16.4.2 Performance Evaluation 212

16.5 SensorOS Bootloader Service 213

16.5.1 SensorOS Bootloader Design Principles 213

16.5.2 Bootloader Implementation 213

17 Cross-layer Issues in TUTWSN 217

17.1 Cross-layer Node Configuration 217

17.1.1 Application Layer 219

17.1.2 Routing Layer 219

17.1.3 MAC Layer 219

17.1.4 Physical Layer 220

17.1.5 Configuration Examples 220

17.2 Piggybacking Data 223

17.3 Self-configuration with Cross-layer Information 224

17.3.1 Frequency and TDMA Selection 224

17.3.2 Connectivity Maintenance 224

17.3.3 Role Selection 225

18 Protocol Analysis Models 227

18.1 PHY Power Analysis 227

18.2 Radio Energy Models 229

18.2.1 TUTWSN Radio Energy Models 230

18.2.2 ZigBee Radio Energy Models 232

18.3 Contention Models 234

18.3.1 TUTWSN Contention Models 234

18.3.2 ZigBee Contention Models 235

18.4 Node Operation Models 238

18.4.1 TUTWSN Throughput Models 238

18.4.2 ZigBee Throughput Models 239

18.4.3 TUTWSN Power Consumption Models 240

18.4.4 ZigBee Power Consumption Models 243

18.5 Summary 245

19 WISENES Design and Evaluation Environment 247

19.1 Features 247

19.2 WSN Design with WISENES 248

19.3 WISENES Framework 249

19.3.1 Short Introduction to SDL 251

19.3.2 WISENES Instantiation 252

19.3.3 Central Simulation Control 253

19.3.4 Transmission Medium 253

19.3.5 Sensing Channel 254

19.3.6 Sensor Node 254

19.4 Existing WISENES Designs 256

19.4.1 TUTWSN Stack 258

19.4.2 ZigBee Stack 260

19.5 WISENES Simulation Results 263

19.5.1 Simulated Node Platforms 264

19.5.2 Accuracy of Simulation Results 266

19.5.3 Protocol Comparison Simulations 268

PART V DEPLOYMENT 277

20 TUTWSN Deployments 279

20.1 TUTWSN Deployment Architecture 280

20.1.1 WSN Server 281

20.1.2 WSN and Gateway 282

20.1.3 Database 282

20.1.4 User Interfaces 282

20.2 Network Self-diagnostics 283

20.2.1 Problem Statement 283

20.2.2 Implementation 284

20.3 Security Experiments 290

20.3.1 Experimental KDC-based Key Distribution and Authentication Scheme 291

20.3.2 Implementation Experiments 291

21 Sensing Applications 293

21.1 Linear-position Metering 293

21.1.1 Problem Statement 293

21.1.2 Implementation 294

21.1.3 Results 296

21.2 Indoor-temperature Sensing 297

21.2.1 WSN Node Design 298

21.2.2 Results 298

21.3 Environmental Monitoring 300

21.3.1 Problem Statement 300

21.3.2 Implementation 300

21.3.3 Results 306

22 Transfer Applications 313

22.1 TCP/IP for TUTWSN 313

22.1.1 Problem Statement 313

22.1.2 Implementation 314

22.1.3 Results 316

22.2 Realtime High-performance WSN 318

22.2.1 Problem Statement 318

22.2.2 Implementation 318

22.2.3 Results 324

23 Tracking Applications 327

23.1 Surveillance System 327

23.1.1 Problem Statement 328

23.1.2 Surveillance WSN Design 328

23.1.3 WSN Prototype Implementation 331

23.1.4 Surveillance WSN Implementation on TUTWSN Prototypes 332

23.2 Indoor Positioning 334

23.2.1 Problem Statement 335

23.2.2 Implementation 335

23.3 Team Game Management 342

23.3.1 Problem Statement 343

23.3.2 Implementation 343

23.3.3 Example Application Scenario 345

PART VI CONCLUSIONS 349

24 Conclusions 351

References 353

Index 369