Weiqiang Shen

An event data recorder (EDR) is a device installed in a vehicle to record information. Similar to a black box in an airplane, an EDR is used in the study of automobile accidents. Many schemes have been proposed that use vehicle network technology to help record EDR data, including schemes involving storing data on roadside units or nearby vehicles and schemes leveraging blockchain technology. However, these schemes do not take into account the vehicle company’s server; with the increased use of autonomous vehicles, the data related to these vehicles are always uploaded to the vehicle company’s server. In this scenario, we classify the situation into different cases, according to whether or not it is an emergency and whether the vehicle and the server are connected. For these cases, we propose a scheme whereby a vehicle uploads the EDR data to a cloud server and sends the evidence of storage to the nearby vehicle through a vehicular ad hoc network. Our scheme offers a fast response due to the use of symmetric cryptography algorithms while also considering security requirements.

Vehicular Ad hoc Networks (VANETs) can help reduce traffic-related accidents by broadcasting Emergency Messages (EMs) in advance between vehicles. Due to the high-speed mobility of VANETs and attenuation of the wireless signal, reliable and fast transmission of EMs is a challenging task. Such as the chosen next-hop vehicle may have driven away from the neighborhood of the sender before receiving the EM, and rerouting may increase the delay when the EMs encounter transmission failure. To this end, we propose a Speed and Position aware Dynamic Routing (SPDR) for EM dissemination in VANETs. First, we introduce a speed metric dynamic greedy routing to provide a dynamic hop-by-hop rebroadcast of the EM. SPDR dynamically shrinks the Routing Decision Area (RDA) range based on the velocity variance of candidate neighbors and prioritizes the farthest vehicle in the shrunk RDA as the optimal next-hop, enhancing the reliable transmission of EMs. Then, we present a collaborative forwarding strategy to enable candidate neighbors to collaborate in communication. In case of transmission failure, SPDR elects the candidate vehicle close to the destination as the forwarder to reduce rerouting. Simulations in a practical motorway scenario using NS-2 and VanetMobiSim show that SPDR outperforms the existing protocols in terms of message delivery ratio, network throughput, and average dissemination delay.

Sensor barrier coverage has been recognized as an appropriate coverage model for intrusion detection, and many achievements have been obtained in two-dimensional terrestrial wireless sensor networks. However, the achievements based on two-dimensional assumption cannot be directly applied in three-dimensional application scenarios, for example, underwater wireless sensor networks. In this article, we aim to devise a fully distributed deployment algorithm for constructing maximum-level underwater strong k-barrier coverage with available mobile sensors in underwater environment to satisfy the requirement of underwater security-related applications. We first analyze how to form underwater strong one-barrier coverage with minimum mobile sensors, based on which we obtain the minimum number of sensors required for constructing underwater strong one-barrier coverage and the corresponding optimal final positions of these sensors. Then, we propose a fully distributed deployment algorithm for constructing maximum-level underwater strong k-barrier coverage with available mobile sensors in three-dimensional underwater environment. We show that the proposed algorithm has a guaranteed termination after a finite time and is able to self-heal the underwater strong k-barrier coverage to deal with sudden sensor failures. Experimental results validate our analysis and show that the proposed algorithm outperforms both Hungarian and HungarianK in terms of duration and achieves performance close to them with respect to several performance metrics.