© The British Computer Society 2018. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com Advance Access publication on 13 March 2018 doi:10.1093/comjnl/bxy026 A Social Utility-Based Dissemination Scheme for Emergency Warning Messages in Vehicular Social Networks NOOR ULLAH 1 ,XIANGJIE KONG 1* ,LIANGTIAN WAN 1 ,HONGLONG CHEN 2 , ZHIBO WANG 3 AND FENG XIA 1 1 Key Laboratory for Ubiquitous Network and Service Software of Liaoning Province, School of Software, Dalian University of Technology, Dalian 116620, China 2 College of Information and Control Engineering, China University of Petroleum, Qingdao 266580, China 3 School of Computer Science, Wuhan University, Wuhan 430072, China * Corresponding author: xjkong@ieee.org In recent years, many schemes have been proposed to disseminate Emergency Warning Messages (EWMs) in VANETs. However, various problems such as broadcast storm, hidden terminal and con- nectivity issues still persist to reduce the efficacy of these systems. In this paper, we propose a novel Social Utility-based Dissemination Scheme (SUDS) for Emergency Warning Messages in Vehicular Social Networks (VSNs). We utilize social properties of nodes such as centrality, interests and friend- ships to mitigate broadcast storm and hidden terminal problems. Furthermore, we employ the hybrid architecture of VSNs to solve connectivity and contact duration-related issues in sparse and high mobil- ity environments. For this purpose, we devise a dual-strategy-based mechanism, where vehicles com- municate with each other in a distributed or centralized manner according to the required situation. In order to evaluate the performance of proposed scheme, we have conducted extensive experiments for a highway scenario under varying vehicular density, vehicular speed and distance, in comparison with the state-of-the-art dissemination schemes. Simulation results have demonstrated the superiority of SUDS over the compared protocols in terms of delivery ratio, transmission delay and total number of transmissions. We have also demonstrated the positive effects of hybrid architecture of VSNs on vari- ous network parameters. Keywords: vehicular social networks; emergency warning messages; social relationships; collision avoidance system Received 30 October 2017; revised 13 January 2018; editorial decision 13 February 2018 Handling editor: Zhaolong Ning 1. INTRODUCTION Vehicular communication technology has seen a tremendous growth in the past two decades to ensure safety and comfort of users through various services and applications. Among these applications, safety services hold the highest priority, as a mas- sive number of human lives can be saved if alerted in advance about a mishap. Studies have shown that the number of vehicles per accident is much higher when a wireless collision avoidance system is not used [1]. In order to provide such safety services, many works have been proposed especially for Vehicular Ad hoc Networks (VANETs). The main objective of these services is to issue Emergency Warning Messages (EWMs) to the drivers that are moving towards a danger zone in both highway and urban scenarios [2, 3]. Therefore, reliable dissemination of EWMs is of utmost importance and requires efficient transmis- sion protocols. However, usually EWMs have to be transmitted to regions far away from the communication range of the source vehicle. Therefore, multi-hop broadcast transmission techniques SECTION C: COMPUTATIONAL INTELLIGENCE,MACHINE LEARNING AND DATA ANALYTICS THE COMPUTER JOURNAL,VOL. 61 NO. 7, 2018 Downloaded from https://academic.oup.com/comjnl/article-abstract/61/7/971/4931623 by Dalian University of Technology user on 14 January 2019