ABSTRACT
Contents 8.1 Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 8.2 Background. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 8.3 Related Works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182 8.4 High-Level Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
8.4.1 Two-Level Routing/Security Architecture . . . . . . . . . . . . . . . . . . . 185 8.4.2 High-Level Security (among Actuators) . . . . . . . . . . . . . . . . . . . . . 187
8.5 Low-Level Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192 8.5.1 Low-Level (in the Domain of Each Actuator) Re-keying . . . 192 8.5.2 Robustness to Key Losses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192 8.5.3 Relationship between SPKs and ZKs . . . . . . . . . . . . . . . . . . . . . . . . 193 8.5.4 Application of the Ripple Key Scheme . . . . . . . . . . . . . . . . . . . . . 194 8.5.5 Detailed Low-Level Security Procedure . . . . . . . . . . . . . . . . . . . . . 195 8.5.6 Dynamic Security Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
8.5.6.1 Sensor Addition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 8.5.6.2 Sensor Death . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 8.5.6.3 New CH Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 8.5.6.4 CH Death . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
8.6 Performance Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199 8.6.1 Jist +SWANS-based WSAN Security Simulation . . . . . . . . . . . . . 199
8.6.1.1 Energy Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 8.6.2 Performance Test Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
8.6.2.1 Reliability Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 8.7 Security Analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
8.7.1 Protection from Various WSAN Attacks . . . . . . . . . . . . . . . . . . . . . 205 8.7.1.1 BK Attacks among Actuators . . . . . . . . . . . . . . . . . . . . . . . 205 8.7.1.2 SK Attacks among Sensors in Each
Actuator Domain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205 8.7.1.3 Relay Attacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 8.7.1.4 Periodical Attacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 8.7.1.5 Man-in-the-Middle Attacks . . . . . . . . . . . . . . . . . . . . . . . . . 206 8.7.1.6 Data-Level Attacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
8.7.2 Security Overhead Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 8.8 Hardware Experiments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
8.8.1 Security Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 8.9 Conclusions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
8.1 Abstract This chapter discusses the challenging security issues in wireless sensor and actuator networks (WSANs), a special type of wireless sensor networks (WSN). Because WSANs have specific network constraints and data transmission requirements compared to general ad hoc networks and other wireless/wired networks, we propose to seamlessly integrate WASN security with a ripple-zone (RZ)-based routing architecture that is scalable and energy efficient. In this research, we also develop a two-level re-keying/rerouting scheme that is able to not only adapt to a dynamic network topology, but also securely update keys for each data transmission session. Moreover, to provide the security for the in-networking processing such as data aggregation in WSANs, we define a multiple-key management scheme in conjunction with our proposed ripple-zone routing architecture. Extensive simulations and hardware experiments have been conducted to verify the energy efficiency and security performance of our security scheme for WSANs.
