# ARNS: Adaptive Relay-Node Selection Method for Message Broadcasting in the Internet of Vehicles
College of Information Engineering, Henan University of Science and Technology, Luoyang 471000, China; [EMAIL_ADDRESS]  
[PERSON]  
1 School of Computer and Communication Engineering, Changsha University of Science and Technology, Changsha 410114, China; [EMAIL_ADDRESS] (D.C.); [EMAIL_ADDRESS] (Y.J.) College of Information Engineering, Henan University of Science and Technology, Luoyang 471000, China; [EMAIL_ADDRESS]  
[PERSON]  
2 College of Information Engineering, Henan University of Science and Technology, Luoyang 471000, China; [EMAIL_ADDRESS]  
[PERSON]  
3 Computer Science Department, Community College, King Saud University, Riyadh 11437, Saudi Arabia; [EMAIL_ADDRESS] (O.A. ); [EMAIL_ADDRESS] (O.A.) Mathematics and Computer Science Department, Faculty of Science, Menoufia University, Shebin-El-kom 32511, Egypt  
3 College of Science and Engineering, Oral Roberts University, Tulsa, OK 74171, USA; [EMAIL_ADDRESS]  
[PERSON]  
3 College of Information Engineering, Henan University of Science and Technology, Luoyang 471000, China; [EMAIL_ADDRESS] (A.T.), [PERSON]  
5 College of Information Engineering, Henan University of Science and Technology, Luoyang 471000, China; [EMAIL_ADDRESS] (O.A.) Mathematics and Computer Science Department, Faculty of Science, Menoufia University, Shebin-El-kom 32511, Egypt
methods) and black-burst-based relay-node selection methods (called black-burst-based methods). Beacon-based methods obtain the information of neighbor nodes by constructing a routing table with periodic flood beacons, while black-burst-based methods obtain the location information of nodes within the communication range of the sender by broadcasting a black-burst in real-time. Because of the utilization of real-time information, black-burst-based methods exhibit better performance. What is more, the beacon-based methods are prone to consume more bandwidth resources due to the periodical beacons [34; 35; 36; 37; 38; 39; 40], while the black-burst-based methods have few such problems. Currently, most modeling and analysis of the relay-node selection [16; 17; 18] do not consider the influence of the complex road structure, and the black-burst-based methods [21; 22; 23; 24; 25; 26] are only applicable to one specific road structure. However, there is usually more than one road structure in real-world Region of Interest (RoI) that messages need to cover; even diverse road structures exist in the communication range of a sender. Therefore, we propose an adaptive relay-node selection method (ARNS) that is based on exponential partition suitable for complex road structures in the real world. In this paper, our contributions are summarized as follows:  
* According to the specific distribution of obstacles in the real world, the optimal position-selection is redefined, and a curved road relay-node selection method suitable for the actual situations is proposed. * A criterion of classifying road structures is proposed to judge the road structure in complex scenarios. * Based on the above work, an adaptive relay-node selection method is designed to suit two real-world situations: the differences of the road structures in the communication range of the different senders, and multiple road structures in the communication range of one sender. The rest of the paper is organized as follows: Section 2 briefly introduces related work on relay-node selection methods. The problems of message broadcasting in RoI, which include complex road structures and the impact of obstacles, are analyzed in Section 3. An adaptive relay-node selection method based on the exponential partition is presented in Section 4. Section 5 demonstrates the performance of ARNS compared to other methods, and finally, we draw conclusions in Section 6.