Mobility impact in IEEE 802.11p infrastructureless vehicular networks

Abstract

Vehicular ad hoc networks (VANETs) are an extreme case of mobile ad hoc networks (MANETs). High speed and frequent network topology changes are the main characteristics of vehicular networks. These characteristics lead to special issues and challenges in the network design, especially at the medium access control (MAC) layer. Due to high speed of nodes and their frequent disconnections, it is difficult to design a MAC scheme in VANETs that satisfies the quality-of-service requirements in all networking scenarios.In this thesis, we provide a comprehensive evaluation of the mobility impact on the IEEE 802.11p MAC performance. The study evaluates basic performance metrics such as packet delivery ratio, throughput, and delay, as well as the impact of mobility factors. The study also presents a relation between the mobility factors and the respective medium access behavior. Moreover, a new unfairness problem according to node relative speed is identified for both broadcast and unicast scenarios. To achieve better performance, we propose two dynamic contention window mechanisms to alleviate network performance degradation due to high mobility. Extensive simulation results show the significant impact of mobility on the IEEE 802.11p MAC performance, an identification of a new unfairness problem in the vehicle-to-vehicle (V2V) communications, and the effectiveness of the proposed MAC schemes.iii Acknowledgements I would like to express my deepest appreciation and gratitude to my supervisor Professor Weihua Zhuang for her guidance, support, and share of knowledge. Professor Zhuang can be considered as a role model for the professional academic supervisor. She gave me the opportunity to choose the topic of my Master's research, and provided me with invaluable suggestions and advice. She always inspired me when discussing research problems. In addition to her solid knowledge that enriched my research, she was always available, professional, helpful, and extremely nice. Her extraordinary commitment to the excellence of research made the opportunity to work with her a true reward of my Master's research.

Fairness Assurance through TXOP Tuning in IEEE 802.11p Vehicle-to-Infrastructure Networks for Drive-Thru Internet Applications

“…The overall aim is to improve the throughput and fairness for all the users. The problem of unfairness due to vehicles having different velocities has been explained for a V2I scenario in [11,12] and for a V2V scenario in [22]. Authors of [11] present an analysis, in which the network that spans the coverage area of RSU is modeled as an M/G/1 queue.…”

“…Several attempts have been made to analyze and evaluate the performance of IEEE 802.11p standard for vehicular networks in terms of throughput and other related measures [11][12][13][14][15][16][17][18][19][20][21][22][23]. In [13,14], authors propose analytical models to evaluate the performance and the reliability of IEEE 802.11a-based V2V safety-related broadcast services in DSRC system on highway.…”

Intelligent Intrusion Detection of Grey Hole and Rushing Attacks in Self-Driving Vehicular Networks

“…The Protocol is an enhancement to the IEEE 802.11 standard but it is known to have an issue in scalability rate [41]. It cannot offer the required time-probabilistic characteristics in dense road scenarios because it was originally designed for low mobility networks.…”

“…It cannot offer the required time-probabilistic characteristics in dense road scenarios because it was originally designed for low mobility networks. Thus, the IEEE 802.11p protocol does not operate efficiently for high density and mobility scenarios in VANETs [41]. Alternatively, it has a minimal scalability capability when there are many self-driving vehicles in the same vicinity [42,43].…”

Gordon—Mills—Welch sequences of period N = 1023

“…Псевдослучайные последовательности (ПСП) с хорошими авто-и взаимокорреляцион-ными свойствами получили широкое распространение как в системах связи и управления [1][2][3][4][5], так и в системах навигации [6,7]. К ним относятся МП, последовательности Голда, малого и большого множеств Касами, последовательности Баркера, Уолша, ГМВП [8][9][10][11].…”