Description
Book SynopsisProvides an up-to-date, in-depth look at the current research, design, and implementation of cooperative vehicle safety communication protocols and technology
Improving traffic safety has been a top concern for transportation agencies around the world and the focus of heavy research and development efforts sponsored by both governments and private industries. Cooperative vehicle systemswhich use sensors and wireless technologies to reduce traffic accidentscan play a major role in making the world''s roads safer.
Vehicle Safety Communications: Protocols, Security, and Privacy describes fundamental issues in cooperative vehicle safety and recent advances in technologies for enabling cooperative vehicle safety. It gives an overview of traditional vehicle safety issues, the evolution of vehicle safety technologies, and the need for cooperative systems where vehicles work together to reduce the number of crashes or mitigate damage when crashes become unavoidab
Table of Contents
Foreword xv
Ralf G. Herrtwich
Foreword xvii
Flavio Bonomi
Foreword xix
Adam Drobot
Preface xxi
Acknowledgments xxv
1 Traffic Safety 1
1.1 Traffic Safety Facts 1
1.1.1 Fatalities 2
1.1.2 Leading Causes of Crashes 3
1.1.3 Current Trends 5
1.2 European Union 5
1.3 Japan 7
1.4 Developing Countries 7
References 8
2 Automotive Safety Evolution 10
2.1 Passive Safety 10
2.1.1 Safety Cage and the Birth of Passive Safety 10
2.1.2 Seat Belts 11
2.1.3 Air Bags 11
2.2 Active Safety 12
2.2.1 Antilock Braking System 12
2.2.2 Electronic Stability Control 13
2.2.3 Brake Assist 13
2.3 Advanced Driver Assistance Systems 14
2.3.1 Adaptive Cruise Control 15
2.3.2 Blind Spot Assist 16
2.3.3 Attention Assist 16
2.3.4 Precrash Systems 16
2.4 Cooperative Safety 17
References 18
3 Vehicle Architectures 20
3.1 Electronic Control Units 20
3.2 Vehicle Sensors 21
3.2.1 Radars 21
3.2.2 Cameras 21
3.3 Onboard Communication Networks 22
3.3.1 Controller Area Network 23
3.3.2 Local Interconnect Network 23
3.3.3 FlexRay 24
3.3.4 Media Oriented Systems Transport 24
3.3.5 Onboard Diagnostics 24
3.4 Vehicle Data 25
3.5 Vehicle Data Security 26
3.6 Vehicle Positioning 27
3.6.1 Global Positioning System 27
3.6.2 Galileo 29
3.6.3 Global Navigation Satellite System 29
3.6.4 Positioning Accuracy 30
References 30
4 Connected Vehicles 32
4.1 Connected Vehicle Applications 32
4.1.1 Hard Safety Applications 32
4.1.2 Soft Safety Applications 33
4.1.3 Mobility and Convenience Applications 33
4.2 Uniqueness in Consumer Vehicle Networks 34
4.3 Vehicle Communication Modes 36
4.3.1 Vehicle-to-Vehicle Local Broadcast 36
4.3.2 V2V Multihop Message Dissemination 37
4.3.3 Infrastructure-to-Vehicle Local Broadcast 38
4.3.4 Vehicle-to-Infrastructure Bidirectional Communications 39
4.4 Wireless Communications Technology for Vehicles 39
References 42
5 Dedicated Short-Range Communications 44
5.1 The 5.9 GHz Spectrum 44
5.1.1 DSRC Frequency Band Usage 45
5.1.2 DSRC Channels 45
5.1.3 DSRC Operations 46
5.2 DSRC in the European Union 46
5.3 DSRC in Japan 47
5.4 DSRC Standards 48
5.4.1 Wireless Access in Vehicular Environments 48
5.4.2 Wireless Access in Vehicular Environments Protocol Stack 48
5.4.3 International Harmonization 50
References 50
6 WAVE Physical Layer 52
6.1 Physical Layer Operations 52
6.1.1 Orthogonal Frequency Division Multiplexing 52
6.1.2 Modulation and Coding Rates 53
6.1.3 Frame Reception 54
6.2 PHY Amendments 55
6.2.1 Channel Width 56
6.2.2 Spectrum Masks 56
6.2.3 Improved Receiver Performance 57
6.3 PHY Layer Modeling 57
6.3.1 Network Simulator Architecture 58
6.3.2 RF Model 59
6.3.3 Wireless PHY 61
References 62
7 WAVE Media Access Control Layer 64
7.1 Media Access Control Layer Operations 64
7.1.1 Carrier Sensing Multiple Access with Collision Avoidance 64
7.1.2 Hidden Terminal Effects 65
7.1.3 Basic Service Set 66
7.2 MAC Layer Amendments 66
7.3 MAC Layer Modeling 67
7.3.1 Transmission 68
7.3.2 Reception 68
7.3.3 Channel State Manager 68
7.3.4 Back-Off Manager 69
7.3.5 Transmission Coordination 70
7.3.6 Reception Coordination 71
7.4 Overhauled ns-2 Implementation 72
References 74
8 DSRC Data Rates 75
8.1 Introduction 75
8.2 Communication Density 76
8.2.1 Simulation Study 77
8.2.2 Broadcast Reception Rates 78
8.2.3 Channel Access Delay 81
8.2.4 Frames Reception Failures 83
8.3 Optimal Data Rate 85
8.3.1 Modulation and Coding Rates 85
8.3.2 Simulation Study 86
8.3.3 Simulation Matrix 87
8.3.4 Simulation Results 88
References 91
9 WAVE Upper Layers 93
9.1 Introduction 93
9.2 DSRC Multichannel Operations 94
9.2.1 Time Synchronization 94
9.2.2 Synchronization Intervals 95
9.2.3 Guard Intervals 96
9.2.4 Channel Switching 96
9.2.5 Channel Switching State Machine 96
9.3 Protocol Evaluation 97
9.3.1 Simulation Study 98
9.3.2 Simulation Scenarios 99
9.3.3 Simulation Results 99
9.3.4 Protocol Enhancements 102
9.4 WAVE Short Message Protocol 103
References 104
10 Vehicle-to-Infrastructure Safety Applications 106
10.1 Intersection Crashes 106
10.2 Cooperative Intersection Collision Avoidance System for Violations 107
10.2.1 CICAS-V Design 107
10.2.2 CICAS-V Development 110
10.2.3 CICAS-V Testing 116
10.3 Integrated Safety Demonstration 118
10.3.1 Demonstration Concept 118
10.3.2 Hardware Components 120
10.3.3 Demo Design 121
References 124
11 Vehicle-to-Vehicle Safety Applications 126
11.1 Cooperation among Vehicles 126
11.2 V2V Safety Applications 127
11.3 V2V Safety Applications Design 128
11.3.1 Basic Safety Messages 129
11.3.2 Minimum Performance Requirements 129
11.3.3 Target Classifi cation 131
11.3.4 Vehicle Representation 132
11.3.5 Sample Applications 133
11.4 System Implementation 135
11.4.1 Onboard Unit Hardware Components 135
11.4.2 OBU Software Architecture 135
11.4.3 Driver–Vehicle Interface 137
11.5 System Testing 138
11.5.1 Communications Coverage and Antenna Considerations 138
11.5.2 Positioning 139
References 140
12 DSRC Scalability 141
12.1 Introduction 141
12.2 DSRC Data Traffic 142
12.2.1 DSRC Safety Messages 142
12.2.2 Transmission Parameters 143
12.2.3 Channel Load Assessment 144
12.3 Congestion Control Algorithms 145
12.3.1 Desired Properties 145
12.3.2 Transmission Power Adjustment 146
12.3.3 Message Rate Adjustment 147
12.3.4 Simulation Study 148
12.4 Conclusions 148
References 149
13 Security and Privacy Threats and Requirements 151
13.1 Introduction 151
13.2 Adversaries 151
13.3 Security Threats 152
13.3.1 Send False Safety Messages Using Valid Security Credentials 152
13.3.2 Falsely Accuse Innocent Vehicles 153
13.3.3 Impersonate Vehicles or Other Network Entities 153
13.3.4 Denial-of-Service Attacks Specific to Consumer Vehicle Networks 154
13.3.5 Compromise OBU Software or Firmware 155
13.4 Privacy Threats 155
13.4.1 Privacy in a Vehicle Network 155
13.4.2 Privacy Threats in Consumer Vehicle Networks 156
13.4.3 How Driver Privacy can be Breached Today 158
13.5 Basic Security Capabilities 159
13.5.1 Authentication 159
13.5.2 Misbehavior Detection and Revocation 160
13.5.3 Data Integrity 160
13.5.4 Data Confidentiality 160
13.6 Privacy Protections Capabilities 161
13.7 Design and Performance Considerations 161
13.7.1 Scalability 162
13.7.2 Balancing Competing Requirements 162
13.7.3 Minimal Side Effects 163
13.7.4 Quantifi able Levels of Security and Privacy 163
13.7.5 Adaptability 163
13.7.6 Security and Privacy Protection for V2V Broadcast 163
13.7.7 Security and Privacy Protection for Communications with Security Servers 164
References 165
14 Cryptographic Mechanisms 167
14.1 Introduction 167
14.2 Categories of Cryptographic Mechanisms 167
14.2.1 Cryptographic Hash Functions 168
14.2.2 Symmetric Key Algorithms 169
14.2.3 Public Key (Asymmetric Key) Algorithms 170
14.3 Digital Signature Algorithms 172
14.3.1 The RSA Algorithm 172
14.3.2 The DSA Algorithm 178
14.3.3 The ECDSA Algorithm 184
14.3.4 ECDSA for Vehicle Safety Communications 194
14.4 Message Authentication and Message Integrity Verifi cation 196
14.4.1 Authentication and Integrity Verifi cation Using Hash Functions 197
14.4.2 Authentication and Integrity Verifi cation Using Digital Signatures 198
14.5 Diffi e–Hellman Key Establishment Protocol 200
14.5.1 The Original Diffie–Hellman Key Establishment Protocol 200
14.5.2 Elliptic Curve Diffie–Hellman Key Establishment Protocol 201
14.6 Elliptic Curve Integrated Encryption Scheme (ECIES) 202
14.6.1 The Basic Idea 202
14.6.2 Scheme Setup 202
14.6.3 Encrypt a Message 202
14.6.4 Decrypt a Message 204
14.6.5 Performance 204
References 206
15 Public Key Infrastructure for Vehicle Networks 209
15.1 Introduction 209
15.2 Public Key Certificates 210
15.3 Message Authentication with Certificates 211
15.4 Certifi cate Revocation List 212
15.5 A Baseline Reference Vehicular PKI Model 213
15.6 Confi gure Initial Security Parameters and Assign Initial Certificates 215
15.6.1 Vehicles Create Their Private and Public Keys 216
15.6.2 Certificate Authority Creates Private and Public Keys for Vehicles 217
15.7 Acquire New Keys and Certifi cates 217
15.8 Distribute Certifi cates to Vehicles for Signature Verifications 220
15.9 Detect Misused Certifi cates and Misbehaving Vehicles 222
15.9.1 Local Misbehavior Detection 223
15.9.2 Global Misbehavior Detection 224
15.9.3 Misbehavior Reporting 224
15.10 Ways for Vehicles to Acquire CRLs 226
15.11 How Often CRLs should be Distributed to Vehicles? 228
15.12 PKI Hierarchy 230
15.12.1 Certifi cate Chaining to Enable Hierarchical CAs 231
15.12.2 Hierarchical CA Architecture Example 231
15.13 Privacy-Preserving Vehicular PKI 233
15.13.1 Quantitative Measurements of Vehicle Anonymity 234
15.13.2 Quantitative Measurement of Message Unlinkability 234
References 235
16 Privacy Protection with Shared Certificates 237
16.1 Shared Certificates 237
16.2 The Combinatorial Certificate Scheme 237
16.3 Certificate Revocation Collateral Damage 239
16.4 Certified Intervals 242
16.4.1 The Concept of Certified Interval 242
16.4.2 Certified Interval Produced by the Original Combinatorial Certificate Scheme 242
16.5 Reduce Collateral Damage and Improve Certified Interval 244
16.5.1 Reduce Collateral Damage Caused by a Single Misused Certificate 245
16.5.2 Vehicles Become Statistically Distinguishable When Misusing Multiple Certificates 248
16.5.3 The Dynamic Reward Algorithm 250
16.6 Privacy in Low Vehicle Density Areas 253
16.6.1 The Problem 253
16.6.2 The Blend-In Algorithm to Improve Privacy 256
References 259
17 Privacy Protection with Short-Lived Unique Certificates 260
17.1 Short-Lived Unique Certificates 260
17.2 The Basic Short-Lived Certificate Scheme 261
17.3 The Problem of Large CRL 263
17.4 Anonymously Linked Certificates to Reduce CRL Size 264
17.4.1 Certificate Tags 264
17.4.2 CRL Processing by Vehicles 265
17.4.3 Backward Unlinkability 267
17.5 Reduce CRL Search Time 268
17.6 Unlinked Short-Lived Certificates 269
17.7 Reduce the Volume of Certificate Request and Response Messages 270
17.8 Determine the Number of Certificates for Each Vehicle 270
References 273
18 Privacy Protection with Group Signatures 274
18.1 Group Signatures 274
18.2 Zero-Knowledge Proof of Knowledge 275
18.3 The ACJT Group Signature Scheme and its Extensions 277
18.3.1 The ACJT Group Signature Scheme 277
18.3.2 The Challenge of Group Membership Revocation 282
18.3.3 ACJT Extensions to Support Membership Revocation 283
18.4 The CG Group Signature Scheme with Revocation 286
18.5 The Short Group Signatures Scheme 288
18.5.1 The Short Group Signatures Scheme 288
18.5.2 Membership Revocation 291
18.6 Group Signature Schemes with Verifier-Local Revocation 292
References 293
19 Privacy Protection against Certificate Authorities 295
19.1 Introduction 295
19.2 Basic Idea 295
19.3 Baseline Split CA Architecture, Protocol, and Message Processing 297
19.4 Split CA Architecture for Shared Certifi cates 301
19.5 Split CA Architecture for Unlinked Short-Lived Certificates 302
19.5.1 Acquire One Unlinked Certifi cate at a Time 302
19.5.2 Assign Batches of Unlinked Short-Lived Certifi cates 304
19.5.3 Revoke Batches of Unlinked Certifi cates 306
19.5.4 Request for Decryption Keys for Certificate Batches 307
19.6 Split CA Architecture for Anonymously Linked Short-Lived Certificates 308
19.6.1 Assign One Anonymously Linked Short-Lived Certificate at a Time 308
19.6.2 Assign Batches of Anonymously Linked Short-Lived Certificates 311
19.6.3 Revoke Batches of Anonymously Linked Short-Lived Certificates 312
19.6.4 Request for Decryption Keys for Certificate Batches 313
References 314
20 Comparison of Privacy-Preserving Certificate Management Schemes 315
20.1 Introduction 315
20.2 Comparison of Main Characteristics 316
20.3 Misbehavior Detection 320
20.4 Abilities to Prevent Privacy Abuse by CA and MDS Operators 321
20.5 Summary 322
21 IEEE 1609.2 Security Services 323
21.1 Introduction 323
21.2 The IEEE 1609.2 Standard 323
21.3 Certificates and Certificate Authority Hierarchy 325
21.4 Formats for Public Key, Signature, Certificate, and CRL 327
21.4.1 Public Key Formats 327
21.4.2 Signature Formats 328
21.4.3 Certificate Format 329
21.4.4 CRL Format 332
21.5 Message Formats and Processing for Generating Encrypted Messages 333
21.6 Sending Messages 335
21.7 Request Certifi cates from the CA 336
21.8 Request and Processing CRL 343
21.9 What the Current IEEE 1609.2 Standard Does Not Cover 344
21.9.1 No Support for Anonymous Message Authentication 344
21.9.2 Separate Vehicle-CA Communication Protocols Are Required 344
21.9.3 Interactions and Interfaces between CA Entities Not Addressed / 346
References 346
22 4G for Vehicle Safety Communications 347
22.1 Introduction 347
22.2 Long-Term Revolution (LTE) 347
22.3 LTE for Vehicle Safety Communications/ 353
22.3.1 Issues to Be Addressed 353
22.3.2 LTE for V2I Safety Communications 353
22.3.3 LTE for V2V Safety Communications 356
22.3.4 LTE Broadcast and Multicast Services 357
References 358
Glossary 360
Index 367
