# A Preemptive-Resume Priority MAC Protocol for Efficient BSM Transmission in UAV-Assisted VANETs
## 2 Related Works
By continuously adapting to changing conditions, this approach aims to enhance the efficiency and effectiveness of communication in vehicular networks. Significant progress has been made in the performance analysis of 802.11P, and [PERSON] [29] proposed the well-known Markov chain model for 802.11 DCF under saturated conditions. Using the Markov chain model, extensive research has been conducted on the performance of 802.11 DCF under saturated conditions [30]. [PERSON] et al. [31] proposed an improved MAC protocol to address communication issues in VANETs. This protocol supports data transmission with multiple priorities and employs p-persistent techniques to manage media access, thereby enhancing network efficiency and performance. In [32], the authors developed a throughput analysis model for the modified protocol and discussed how to optimize network performance through access control. By analyzing throughput and access control, this paper provides valuable insights for understanding and optimizing the performance of IEEE 802.11a networks. The application of queuing theory as a mathematical foundation for this protocol is also of great research significance. In [33], the signal transfer function of the generalized state transition graph was derived to describe the probability distribution of the MAC layer service time, and the M/G/1/K and M/M/1/K models were used to characterize the 802.11 MAC layer. Through these improvements, the protocol's throughput can be enhanced, latency can be reduced, and network stability and reliability can be improved. The FPMDC-MAC [34] protocol algorithm is a notable contribution in the field of VANETs, specifically focusing on the MAC layer. This algorithm introduces a fuzzy logic-based priority assignment mechanism to ensure the efficient transmission of important information. Additionally, it incorporatesa cooperative MAC protocol to facilitate communication coordination among vehicles, thereby improving data transmission efficiency. By modifying the 802.11p protocol and incorporating a priority scheme, FPMDC-MAC demonstrates significant enhancements over the existing protocol. In a related study by [PERSON] [35], an improvement approach for enhancing the performance of the IEEE 802.11p/bd MAC protocol is presented. This approach utilizes a 2-D Markov chain model and queuing theory to construct the model, which shares similar methodologies with our research. However, it does not incorporate priority-related schemes, which constitutes a distinct advantage of our work. In [36], [PERSON] proposed a hybrid MAC protocol based on priority, which combines slot allocation with a carrier sense multiple access (CSMA) mechanism. By incorporating priority assignment and dynamic slot allocation strategies, this protocol achieves fair sharing and efficient utilization of network resources among vehicles with different priorities. The paper also provided detailed deployment schemes for unmanned aerial vehicles, demonstrating that the protocol effectively improves network throughput, latency, and reliability while ensuring fair sharing and balanced resource utilization among vehicles with different priorities. In [37], the author [PERSON] aimed to design a conflict-free cooperative MAC protocol to address the issue of heterogeneous collisions in VANETs caused by differences in vehicle speeds, communication ranges, and data transmission requirements. The protocol utilizes a cooperation mechanism among vehicles by dividing neighboring vehicles into multiple groups, where only one vehicle in each group is allowed to transmit data, while others act as relay nodes for data forwarding. This approach enables vehicles with different speeds and communication ranges to share network resources, reducing the probabilities of heterogeneous collisions and packet loss, thus improving network performance and stability. Ref.