Security Threats in Vehicular Ad Hoc Networks Ahmed Shoeb Al Hasan 1 - PDF document

2016 Intl. Conference on Advances in Computing, Communications and Informatics (ICACCI), Sept. 21-24, 2016, Jaipur, India Security Threats in Vehicular Ad Hoc Networks Ahmed Shoeb Al Hasan 1 , Md. Shohrab Hossain 1 , and Mohammed Atiquzzaman 2 1 Department of Computer Science & Engineering, Bangladesh University of Engineering & Technology, Dhaka, Bangladesh 2 School of Computer Science, University of Oklahoma, Norman, OK 73019, USA Email: shoeb.al.hasan@gmail.com, mshohrabhossain@cse.buet.ac.bd, atiq@ou.edu Abstract — A new type of Mobile Ad Hoc Network (MANET) messages can be transmitted using V2V communications to is Vehicular Ad Hoc Network (VANET) that allows smart avoid accidents and traffic congestions. transport system to provide road security and reduce traffic jam through automobile to automobile and automobile to roadside communication. However, security issues for VANETs have become a major concern for researchers. VANET is different from other ad hoc networks due to its dynamic topology and mixed structural design. Hence, designing security schemes to authenticate broadcasted messages and discard malicious messages are crucial in VANETs. Here, at first we identify various security issues for VANET and discuss possible defense mechanisms to mitigate those threats. We then classify the defense mechanisms into major categories and critically analyze them based on different performance criteria. Finally, we list several open research issues related to VANET security to inspire researchers to work on these open problems and propose solutions towards efficient trust organization in VANET. Fig. 1: Vehicular Ad Hoc Network (VANET). Keywords—Vehicular Ad Hoc Network, VANET, Mobile Ad VANETs are required to implement security measures, for Hoc Network, MANET, Cryptography, V2V communication, instance, secrecy, reliability and approval to offer protection Security Threat. against invaders and mischievous nodes since VANETs transmit emergency, life critical real-time information. I. I NTRODUCTION Wormhole attack [4-5], Purposeful attack [6], Illusion attack VANETs are a subgroup of MANETs where [7], Denial of Service (DoS) [8], Sybil attack [ 9-11 ] are communicating nodes are mainly vehicles and roadside some of the security attacks which can hamper the privacy of infrastructures. At present, VANETs have many the person driving the vehicle as well as the vehicle. implementations focusing different aspects of transport Eventually, these attacks may cause death of human lives by systems, like, driving assistance, public security, roadside reducing traffic safety. Hence, many researchers are facility locator, toll collection, road traffic control, freeway extensively working on the security of VANETs. The primary internet connection and increasing security and efficacy of reason of providing security in VANET is necessary so that freeway systems. Through the use of Dedicated Short-Range the original identity of the drivers cannot be disclosed at any Communication (DSRC)[2], VANETs support Intelligent time in VANET since malicious nodes can launch attacks Transportation System (ITS) [1]. Wireless Access in using this information as false identity. During V2I Vehicular Environment (WAVE) [3] is one of the standards communication safety and privacy is very important since to implement VANET. Fig. 1 illustrates the basic topology of drivers and vehicles have to disclose their identity to VANET. communicate with RSUs. Vehicles need to ensure the authenticity of the received information before reacting to the Two types of communication technologies are implemented received information. for VANET. One is Vehicle to Vehicle (V2V) and another is Vehicle to Infrastructure (V2I). Vehicles consist of GPS, There are several surveys on the security threats of processors, sensors and antennas which are known as On VANET [12-14]. La et al. [12] presented some security Board Unit (OBUs) to correspond with other vehicles. threats and differentiated them, but no defense mechanism Vehicles also communicate with infrastructures at the roadside has been discussed. Tangade et al. [13] discussed some trust at a static distance from each other known as Road Side Units models to eliminate the threats in VANET networks. Al- (RSUs). RSUs can be mobile and they use wired or wireless Kahtani [14] proposed some approaches to defend security medium to communicate with each other and the Internet. threats. However, there exists no work that presents a Vehicles can be connected to Internet through V2I since RSUs complete comparative study among the defense mechanisms. are connected to the Internet. Real time and emergency In our earlier works [30-31], we have presented security 404 978-1-5090-2029-4/16/$31.00 @2016 IEEE

2016 Intl. Conference on Advances in Computing, Communications and Informatics (ICACCI), Sept. 21-24, 2016, Jaipur, India issues for mobility management protocols in space networks Basically there are two types of applications in VANET, [30], and presented a comparative study on the defense one is safety related applications and another is comfort mechanism for mobility management protocols in such applications. networks [31]. A. Safety Applications The contributions of this paper are (i) identifying and These VANET applications aim to save human lives in the illustrating the threats for VANET networks, (ii) outlining the streets. The feature of these safety applications is to deliver the defense mechanisms that can be applied to the respective safey related data to the actual receiver in time. Safety related threats, and (iii) critical analysis and comparison among applications are listed as follows: different defense mechanisms based on performance criteria. 1) Assistance Messages (AM): These messages include The rest of the paper is organized as follows. Section II lane switching messages, cooperative collision avoidance presents the basics of VANET and its applications. In Section (CCA), and navigating. Preventing collisions is the main goal III, we discuss the some of VANET security threats and their of CCA. If there is a possibility of a collision among the mitigation approaches. In Section IV, we classify the defense vehicles nearby, these applications will trigger automatically mechanisms and critically analyze and compare them. In to warn the driver to steer the vehicle or reduce the speed, Section V, several open research issues related to VANET thereby avoiding possible collision(s). Vehicles detecting an security have been discussed. Finally, concluding remarks are accident may start sending messages to other vehicles so that discussed in the Section VI. others may take a detour (see Fig. 2). II. VANET 2) Information Messages (IMs) : Examples of such VANETs are special type of MANETs where all the messages are work zone information, in the highway, toll communicating nodes are vehicles. But many features of point ahead, and speed limit.. VANET are different from MANET such as cost of VANET is higher than MANET. Due to the higher speed of vehicles 3) Warning Messages (WMs): Examples of WMs are over mobile nodes, VANET’s network topology changes post-crash, obstacle, stop light (ahead) in a highway, toll point, rapidly in contrast to MANET. The nodes move in pre-defined or road condition warnings. Vehicles may start transmiting paths in VANET but in MANET nodes move randomly. WMs to other vehicles in a certain zone after sensing it, VANET requires more bandwidth than MANET to manage thereby helping other subsequent vehicles reducing their speed mobility signaling. Table I illustrates the key differences to avoid accidents [15]. between VANET and MANET. Table I: Differences between VANET and MANET. Category VANET MANET Cost Expensive Inexpensive Change of network Frequent Slow topology Mobility High Low Bandwidth Thousand Kbps Hundred Kbps Range Up to 600m Up to 100m Density of nodes Dense Sparse Reliability High Medium Fig. 2. Safety application : warning for possible accident. Dependent on Dependent on Node lifetime B. Comfort Applications vehicle lifetime power source Improving passenger comfort and traffic efficiency is the Moving pattern of Regular Random main objective of comfort applications. These applications nodes can be included in Value Added Services (VASs) which can be used by VANET. Passengers in a vehicle for a long period VANETs have to deal with high mobility of nodes. In would be interested to use some applications from vehicular VANET, there are different types of communications. As networks. shown in Fig. 1, a vehicle can contact with another vehicle, known as Vehicle-to-Vehicle (V2V) communication. Also, Some of the applications are as follows: vehicles need to transmit information with roadside 1) Automatic toll collection: Using this service, payment is infrastructures, known as Vehicle to Infrastructure (V2I) completed electronically. So the vehicle doesn’t need to stop communication. Moreover, road-side unit / infrastructures at to pay the fees. the roadside communicate with one another. Communication in VANET is very challenging due to its high mobility. 2) Location based aplications: Location of restaurants, gas station, shopping malls, ATMs etc. can be uploaded to the 405