Analysis of Security Overhead in Broadcast V2V Communications

This paper concerns security issues for broadcast vehicle to vehicle (V2V) messages carrying vehicle status information ((location, heading, speed, etc.). These are often consumed by safety-related applications that e.g. augment situational awareness, issue alerts, recommend courses of action, and even trigger autonomous action. Consequently, the messages need to be both trustworthy and timely. We explore the impact of authenticity and integrity protection mechanisms on message latency using a model based on queuing theory. In conditions of high traffic density such as found in busy city centres, even the latency requirement of 100ms for first generation V2V applications was found to be challenging. Our main objective was to compare the performance overhead of the standard, PKC-based, message authenticity and integrity protection mechanism with that of an alternative scheme, TESLA, which uses symmetric-key cryptography combine with hash chains. This type of scheme has been dismissed in the past due to sup-posed high latency, but we found that in high traffic density conditions it outperformed the PKC-based scheme. without invoking congestion management measures. Perhaps the most significant observation from a security perspective is that denial of service attacks appear very easy to carry out and hard to defend against. This merits attention from the research and practitioner communities and is a topic we intend to address in the future

How many vehicles in the LTE-V2V awareness range with half or full duplex radios?

Given the increasing interest for future connected vehicles, the long term evolution (LTE) specifications are being enhanced by 3GPP to cope with the vehicle-to-everything (V2X) scenarios starting from the upcoming Release 14, which will include, among others, vehicle-to-vehicle (V2V) direct communications. Since the main service expected for connected vehicles is the cooperative awareness, in this work we aim at deriving the number of neighbors that can be managed by LTE-V2V. In addition to the normal half duplex (HD) radios, which strictly limit the granularity of resource allocation, advanced full duplex (FD) radios are also considered. Results show that LTE-V2V with HD radios is able to manage up to few tens of neighbors, whereas FD can increase this limit significantly at the expense of an increase of complexity

Performance Analysis of FD-NOMA-based Decentralized V2X Systems

In order to meet the requirements of massively connected devices, different quality of services (QoSs), various transmit rates and ultra-reliable and low latency communications (URLLC) in vehicle to everything (V2X) communications, we introduce a full duplex non-orthogonal multiple access (FD-NOMA)-based decentralized V2X system model. We then classify the V2X communications into two scenarios and give their exact capacity expressions. To solve the computation complicated problems of the involved exponential integral functions, we give the approximate closed-form expressions with arbitrary small errors. Numerical results indicate the validness of our derivations. Our analysis has that the accuracy of our approximate expressions is controlled by the division of π/2 in the urban and crowded scenario, and the truncation point T in the suburban and remote scenario. Numerical results manifest 1) Increasing the number of V2X device, NOMA power and Rician factor value yields better capacity performance. 2) Effect of FD-NOMA is determined by the FD self-interference and the channel noise. 3) FD-NOMA has better latency performance compared to other schemes

Performance of Sensing-Based Semi-Persistent Scheduling (SPS) in LTE-V2X Release 14 Distributed Mode

This project will study the different possibilities of access technologies based on LTE in order to provide communications V2V and V2I. This evaluation will be performed by developing a simulator and studying its main communication parameters.The initial standard for cellular-based Vehicle-to-everything (V2X) communications was introduced in 2017 by 3GPP in Long Term Evolution (LTE) Release 14 to serve as a viable alternative to the mature yet dated WLAN-based 802.11p technology. LTE-V2X Release 14 introduced a new arrangement of the resource grid as well as a sensing-based semi-persistent scheduling (SPS) algorithm for the distributed mode in order to reduce latency and increase capacity. A simulator based on open-source software frameworks was developed to evaluate the performance of the Release 14 sensing-based SPS and random allocation in scenarios with varying traffic loads, message sizes, resource keep probabilities P, and collision power thresholds. The performance was then evaluated in terms of Packet Reception Ratio (PRR), occupancy, and goodput, Neighborhood Awareness Ratio (NAR), position error, and latency. Simulation results showed that sensing-based SPS generally performed better than random allocation in terms of PRR in short to medium distances. Sensing-based SPS configured with P=0 performed only slightly better than random allocation in terms of NAR but slightly worse in terms of position error. However, with sufficiently high message traffic, sensing-based SPS performed similar to, or even worse than random allocation