Cooperative Jamming-Based Physical-Layer Group Secret and Private Key Generation.

This paper explores physical layer group key generation in wireless relay networks with a star topology. In this setup, the relay node plays the role of either a trusted or untrusted central node, while one legitimate node (Alice) acts as the reference node. The channel between the relay and Alice serves as the reference channel. To enhance security during the channel measurement stage, a cooperative jamming-based scheme is proposed in this paper. This scheme allows the relay to obtain superimposed channel observations from both the reference channel and other relay channels. Then, a public discussion is utilized to enable all nodes to obtain estimates of the reference channel. Subsequently, the legitimate nodes can agree on a secret key (SK) that remains secret from the eavesdropper (Eve), or a private key (PK) that needs to be secret from both the relay and Eve. This paper also derives the lower and upper bounds of the SK/PK capacity. Notably, it demonstrates that there exists only a small constant difference between the SK/PK upper and lower bounds in the high signal-to-noise ratio (SNR) regime. Simulation results confirm the effectiveness of the proposed scheme for ensuring security and efficiency of group key generation.

An efficient multilevel security architecture for blockchain-based IoT networks using principles of cellular automata.

The tremendous increase in the use of Internet of Things (IoT) has made an impact worldwide by changing the mode of day-to-day life. Like any other application, IoT based networks also have to be protected since the data produced consist of sensitive information. Existing algorithms for providing security in such networks do not consider all the security objectives. Starting from the sensing of data from IoT environment, the data have to be protected from several types of attacks. Also, the authentication of involved entities, integrity of data, access control and confidentiality are to be achieved. This work proposes a novel security architecture for IoT based distributed applications. The architecture uses the best known lightweight cipher ChaCha20. Principles of cellular automata are applied for random number generation to attain more security and randomness. Double encryption ensures multilevel protection of data during the data uploading and storing phases. Providing encryption based on dynamic session keys guarantees the security of the method. It also ensures secure data sharing, mutual authentication between communicating entities, fast execution, user authentication and message integrity. The IoT device connected to a gateway node has to complete registration phase successfully. Subsequently, each time a data transfer between the device and gateway node takes place, mutual authentication phase is executed. Blockchain network used at the edge level ensures authentication of participating nodes and hence, unintended modification of data is prevented. The proposed architecture proves to be efficient in terms of throughput, execution time and resistance to various security attacks.

A Scalable and Secure Group Key Management Method for Secure V2V Communication.

Safety applications based on vehicle-to-everything (V2X) communications can significantly enhance road safety and reduce traffic fatalities. Ensuring the security and privacy of the vehicular network is essential for the widespread adoption of V2X communications for commercial use. V2X safety and service applications require periodic broadcast communications among all the vehicles. However, compared to unicast communication, it is extremely challenging to provide broadcast communication with network security requirements such as confidentiality, in infotainment contents distribution, sensor data sharing, and security credentials management services. To address the providing confidentiality of vehicle-to-vehicle (V2V) broadcasting, we propose a group key management and message encryption method that is secure, lightweight, and scalable. The proposed group key management method can efficiently handle various scenarios like a node joining or leaving the group, with scalable rekeying algorithms. It employs a distributed and scalable architecture that offers several advantages such as the reduction of the key management overhead and the enhancement of the security level by keeping the key sizes with large networks. In addition, the proposed method employs a lightweight matrix-based encryption algorithm that can be easily applicable with the proposed group key management method. Further, we have implemented the proposed method and evaluated the performance using a V2V network simulator with several networks of highly dynamic group members. The simulation results show that the proposed method can reduce computation time for group key generation and message encryption by more than 80% compared to existing methods.