Currently, there is a growing belief that putting an IEEE 802.11-like radio into road vehicles can help the drivers to travel more safely. Message dissemination protocols are primordial for safety vehicular applicatio...Currently, there is a growing belief that putting an IEEE 802.11-like radio into road vehicles can help the drivers to travel more safely. Message dissemination protocols are primordial for safety vehicular applications. There are two types of safety messages which may be exchanged between vehicles: alarm and beacon. In this paper we investigate the feasibility of deploying safety applications based on beacon message dissemination through extensive simulation study and pay special attention to the safety requirements. Vehicles are supposed to issue these messages periodically to announce to other vehicles their current situation and use received messages for preventing possible unsafe situations. We evaluate the performance of a single-hop dissemination protocol while taking into account the quality of service (QoS) metrics like delivery rate and delay. We realize that reliability is the main concern in beacon message dissemination. Thus, a new metric named effective range is defined which gives us more accurate facility for evaluating QoS in safety applications specifically. Then, in order to improve the performance, the effects of three parameters including vehicle's transmission range, message transmission's interval time and message payload size are studied. Due to special characteristics of the safety applications, we model the relationship between communication-level QoS and application-level QoS and evaluate them for different classes of safety applications. As a conclusion, the current technology of IEEE 802.11 MAC layer has still some challenges for automatic safety applications but it can provide acceptable QoS to driver assistance safety applications.展开更多
As Vehicular ad hoc networks (VANETs) become more sophisticated, the importance of integrating data protection and cybersecurity is increasingly evident. This paper offers a comprehensive investigation into the challe...As Vehicular ad hoc networks (VANETs) become more sophisticated, the importance of integrating data protection and cybersecurity is increasingly evident. This paper offers a comprehensive investigation into the challenges and solutions associated with the privacy implications within VANETs, rooted in an intricate landscape of cross-jurisdictional data protection regulations. Our examination underscores the unique nature of VANETs, which, unlike other ad-hoc networks, demand heightened security and privacy considerations due to their exposure to sensitive data such as vehicle identifiers, routes, and more. Through a rigorous exploration of pseudonymization schemes, with a notable emphasis on the Density-based Location Privacy (DLP) method, we elucidate the potential to mitigate and sometimes sidestep the heavy compliance burdens associated with data protection laws. Furthermore, this paper illuminates the cybersecurity vulnerabilities inherent to VANETs, proposing robust countermeasures, including secure data transmission protocols. In synthesizing our findings, we advocate for the proactive adoption of protective mechanisms to facilitate the broader acceptance of VANET technology while concurrently addressing regulatory and cybersecurity hurdles.展开更多
Wireless Ad Hoc Networks consist of devices that are wirelessly connected.Mobile Ad Hoc Networks(MANETs),Internet of Things(IoT),and Vehicular Ad Hoc Networks(VANETs)are the main domains of wireless ad hoc network.Int...Wireless Ad Hoc Networks consist of devices that are wirelessly connected.Mobile Ad Hoc Networks(MANETs),Internet of Things(IoT),and Vehicular Ad Hoc Networks(VANETs)are the main domains of wireless ad hoc network.Internet is used in wireless ad hoc network.Internet is based on Transmission Control Protocol(TCP)/Internet Protocol(IP)network where clients and servers interact with each other with the help of IP in a pre-defined environment.Internet fetches data from a fixed location.Data redundancy,mobility,and location dependency are the main issues of the IP network paradigm.All these factors result in poor performance of wireless ad hoc networks.The main disadvantage of IP is that,it does not provide in-network caching.Therefore,there is a need to move towards a new network that overcomes these limitations.Named Data Network(NDN)is a network that overcomes these limitations.NDN is a project of Information-centric Network(ICN).NDN provides in-network caching which helps in fast response to user queries.Implementing NDN in wireless ad hoc network provides many benefits such as caching,mobility,scalability,security,and privacy.By considering the certainty,in this survey paper,we present a comprehensive survey on Caching Strategies in NDN-based Wireless AdHocNetwork.Various cachingmechanism-based results are also described.In the last,we also shed light on the challenges and future directions of this promising field to provide a clear understanding of what caching-related problems exist in NDN-based wireless ad hoc networks.展开更多
There is a significant increase in the rates of vehicle accidents in countries around the world and also the casualties involved ever year. New technologies have been explored relating to the Vehicular Ad Hoc Network ...There is a significant increase in the rates of vehicle accidents in countries around the world and also the casualties involved ever year. New technologies have been explored relating to the Vehicular Ad Hoc Network (VANET) due to the increase in vehicular traffic/congestions around us. Vehicular communication is very important as technology has evolved. The research of VANET and development of proposed systems and implementation would increase safety among road users and improve the comfort for the corresponding passengers, drivers and also other road users, and a great improvement in the traffic efficiency would be achieved. This research paper investigates the current and existing security issues associated with the VANET and exposes any slack amongst them in order to lighten possible problem domains in this field.展开更多
In this paper we analyze connectivity of one-dimensional Vehicular Ad Hoc Networks where vehicle gap distribution can be approximated by an exponential distribution. The probabilities of Vehicular Ad Hoc Network conne...In this paper we analyze connectivity of one-dimensional Vehicular Ad Hoc Networks where vehicle gap distribution can be approximated by an exponential distribution. The probabilities of Vehicular Ad Hoc Network connectivity for difference cases are derived. Furthermore we proof that the nodes in a sub-interval [z1,z1 +Δz] of interval [0, z], z>0 where all the nodes are independently uniform distributed is a Poisson process and the relationship of Vehicle Ad hoc Networks and one-dimensional Ad Hoc networks where nodes independently uniform distributed in [z1,z1 +Δz] is explained. The analysis is validated by computing the probability of network connectivity and comparing it with the Mont Carlo simulation results.展开更多
Vehicular Ad hoc Networks(VANETs)become a very crucial addition in the Intelligent Transportation System(ITS).It is challenging for a VANET system to provide security services and parallelly maintain high throughput b...Vehicular Ad hoc Networks(VANETs)become a very crucial addition in the Intelligent Transportation System(ITS).It is challenging for a VANET system to provide security services and parallelly maintain high throughput by utilizing limited resources.To overcome these challenges,we propose a blockchain-based Secured Cluster-based MAC(SCB-MAC)protocol.The nearby vehicles heading towards the same direction will form a cluster and each of the clusters has its blockchain to store and distribute the safety messages.The message which contains emergency information and requires Strict Delay Requirement(SDR)for transmission are called safety messages(SM).Cluster Members(CMs)sign SMs with their private keys while sending them to the blockchain to confirm authentication,integrity,and confidentiality of the message.A Certificate Authority(CA)is responsible for physical verification,key generation,and privacy preservation of the vehicles.We implemented a test scenario as proof of concept and tested the safety message transmission(SMT)protocol in a real-world platform.Computational and storage overhead analysis shows that the proposed protocol for SMT implements security,authentication,integrity,robustness,non-repudiation,etc.while maintaining the SDR.Messages that are less important compared to the SMs are called non-safety messages(NSM)and vehicles use RTS/CTS mechanism for NSM transmission.Numerical studies show that the proposed NSM transmission method maintains 6 times more throughput,2 times less delay and 125%less Packet Dropping Rate(PDR)than traditional MAC protocols.These results prove that the proposed protocol outperforms the traditional MAC protocols.展开更多
In this paper, we present an analytical model to determine the network connectivity probability of a linear vehicular ad hoc network (VANET) formed by communication equipped vehicles on a two-way street scenario. We c...In this paper, we present an analytical model to determine the network connectivity probability of a linear vehicular ad hoc network (VANET) formed by communication equipped vehicles on a two-way street scenario. We consider the highway to be consisting of two lanes with vehicles moving in both directions on these lanes and focus on the probability of being able to convey messages from a source vehicle to a destination vehicle, which may be multiple hops away. Closed form analytical expression is obtained for the network connectivity probability in the presence of Nakagami fading channel. In our model, the transmission range of each vehicle is modeled as a random variable due to channel fading. The analytical results are validated by extensive simulations.展开更多
Due to high node mobility, stability has been always one of the major concerns of vehicle clustering algorithms in vehicular ad hoc networks. In this paper, we propose a novel clustering algorithm based on the informa...Due to high node mobility, stability has been always one of the major concerns of vehicle clustering algorithms in vehicular ad hoc networks. In this paper, we propose a novel clustering algorithm based on the information of routes planned by vehicular navigation systems. In the clustering algorithm, we design a residual route time function to quantitatively calculate the overlapping time among vehicles based on route information, with which a novel clusterhead selection metric is presented. We further design a mechanism of future-clusterhead, which can help avoid message exchanges at intersections and reduce the overhead of cluster maintenance. The simulation results show that, compared with previous works, our clustering algorithm can achieve higher stability and at the same time lower communication cost.展开更多
This paper studies a routing protocol used in the application of collecting real-time traffic informationusing mobile vehicles to monitor traffic status. The biggest challenge of vehicular ad hoc network routingprotoc...This paper studies a routing protocol used in the application of collecting real-time traffic informationusing mobile vehicles to monitor traffic status. The biggest challenge of vehicular ad hoc network routingprotocol lies in the mismatch between the direction of moving vehicles and routed data. In order to dealwith this mismatch, a mesh based routing protocol with a two-tier network architecture is proposed. Byusing mesh nodes deployed at intersections, data can be routed through an optimized path which can improvethe delivery ratio and reduce the consumption of network resources. The simulation uses the mobilitymodel processed from the GPS data of taxis running in Shanghai urban areas. The result shows that theproposed protocol outperforms the existing flooding protocol.展开更多
With the rapid development of vehicular ad hoc network( VANET) technology,VANET applications such as safe driving and emergency rescue demand high position accuracy,but traditional GPS is difficult to meet new accurac...With the rapid development of vehicular ad hoc network( VANET) technology,VANET applications such as safe driving and emergency rescue demand high position accuracy,but traditional GPS is difficult to meet new accuracy requirements. To overcome this limitation,a new vehicle positioning method based on radio frequency identification( RFID) is proposed. First RFID base stations are divided into three categories using fuzzy technology,and then Chan algorithm is used to calculate three vehicles' positions,which are weighed to acquire vehicles' accurate position. This method can effectively overcome the problem that vehicle positioning accuracy is not high resulting from the factors such as ambient noise and base distribution when Chan algorithm is used. Experimental results show that the performance of the proposed method is superior to Chan algorithm and 2-step algorithm based on averaging method,which can satisfy the requirements of vehicle positioning in VANETs.展开更多
In this paper,we investigate the connectivity of vehicular ad hoc networks in free-flow traffic situationwith channel randomness.In order to illustrate the realistic environment,we consider that vehiclesare distribute...In this paper,we investigate the connectivity of vehicular ad hoc networks in free-flow traffic situationwith channel randomness.In order to illustrate the realistic environment,we consider that vehiclesare distributed in free-flow highway according to a Poisson point process,and signal propagation betweenconnected vehicles is subjected to log-normal shadowing effects.We obtain the distribution of the spaceheadway between successive vehicles and the distribution of signal coverage,which allows us to use theequivalent M/G/∞ queue theory to model the connectivity of VANETs in the form of average broadcastpercolation distance and average number of connected nodes.Then,extensive simulation studies are conductedto evaluate the obtained results.The analytical model presented here is able to describe the impactof various system parameters,including traffic parameters and signal propagation parameters on the connectivity.We use our analytical results,along with the common signal propagation data,to understandimpact of channel randomness on the connectivity of VANETs.展开更多
The problem of information dissemination is researched for vehicular ad-hoc networks(VANET)inthis paper,and a contention-based efficient-information perception algorithm(CEiPA)is proposed.Theidea of CEiPA is that beac...The problem of information dissemination is researched for vehicular ad-hoc networks(VANET)inthis paper,and a contention-based efficient-information perception algorithm(CEiPA)is proposed.Theidea of CEiPA is that beacons are delivered over VANET with limited lifetime and efficient information.CEiPA consists of two phases.The first one is initialization phase,during which the count timers T_(cycle)and T_(local)are set to start beacon delivery while T_(cycle)is also used to monitor and restart beaconing.Thesecond one is beacon delivery phase.An elaborate distance function is employed to set contention delayfor beacons of each vehicle.In this way beacons will be sent in order,which decreases the collision ofbeacons.Simulation results show that CEiPA enables each beacon to carry more efficient information andspread them over more vehicles with lower network overhead than the periodic beacon scheme.CEiPA isalso flexible and scalable because the efficient information threshold it employs is a balance among thefreshness of information,network overhead and perception area of a vehicle.展开更多
In vehicular ad-hoc networks (VANETs), store-carry-forward approach may be used for data sharing, where moving vehicles carry and exchange data when they go by each other. In this approach, storage resource in a vehic...In vehicular ad-hoc networks (VANETs), store-carry-forward approach may be used for data sharing, where moving vehicles carry and exchange data when they go by each other. In this approach, storage resource in a vehicle is generally limited. Therefore, attributes of data that have to be stored in vehicles are an important factor in order to efficiently distribute desired data. In VANETs, there are different types of data which depend on the time and location. Such kind of data cannot be deployed adequately to the requesting vehicles only by popularity-based rule. In this paper, we propose a data distribution method that takes into account the effective life and area in addition to popularity of data. Our extensive simulation results demonstrate drastic improvements on acquisition performance of the time and area specific data.展开更多
This work proposes authentication based on identity as a way to increase the efficiency and security of communications in vehicular ad-hoc networks. When using identity-based cryptography to achieve certificateless au...This work proposes authentication based on identity as a way to increase the efficiency and security of communications in vehicular ad-hoc networks. When using identity-based cryptography to achieve certificateless authentication, membership revocation is not a trivial problem. Thus, in order to improve the performance of revocation in such networks, the use of a dynamic authenticated data structure based on perfect k-ary hash trees combined with a duplex version of the new standard SHA-3 is here presented. Efficient algorithms in the used revocation trees allow reaching a refresh rate of at most simple updates per inserted node. Consequently, the proposal is especially useful for situations with frequent revocations, which are foreseeable when vehicular ad- hoc networks are widely deployed.展开更多
This paper comes up with a SDN Based Vehicle Ad-Hoc On-Demand Routing Protocol(SVAO),which separates the data forwarding layer and network control layer,as in software defined networking(SDN),to enhance data transmiss...This paper comes up with a SDN Based Vehicle Ad-Hoc On-Demand Routing Protocol(SVAO),which separates the data forwarding layer and network control layer,as in software defined networking(SDN),to enhance data transmission efficiency within vehicle ad-hoc networks(VANETs).The roadside service unit plays the role of local controller and is in charge of selecting vehicles to forward packets within a road segment.All the vehicles state in the road.Correspondingly,a two-level design is used.The global level is distributed and adopts a ranked query scheme to collect vehicle information and determine the road segments along which a message should be forwarded.On the other hand,the local level is in charge of selecting forwarding vehicles in each road segment determined by the global level.We implement two routing algorithms of SVAO,and compare their performance in our simulation.We compare SVAO with popular ad-hoc network routing protocols,including Optimized Link State Routing(OLSR),Dynamic Source Routing(DSR),Destination Sequence Distance Vector(DSDV),and distance-based routing protocol(DB)via simulations.We consider the impact of vehicle density,speed on data transmission rate and average packet delay.The simulation results show that SVAO performs better than the others in large-scale networks or with high vehicle speeds.展开更多
Due to highly dynamic topology caused by fast moving nodes the Vehicular ad-hoc network (VANET) results in the existence of transient communication links, which degrade the performance of developed protocols. Establis...Due to highly dynamic topology caused by fast moving nodes the Vehicular ad-hoc network (VANET) results in the existence of transient communication links, which degrade the performance of developed protocols. Established routes frequently become stale, and existing communication flows are interrupted, incurring delay and additional overhead. In this paper we propose a novel hybrid routing protocol, which is the combined between of the table-driven routing and on-demand routing in VANET. It makes fast convergence in routing process, minimal drop links, making more reliable links, and adaptive with changing of VANET topology. With neighbor table is updated instantaneously, and using strong neighbor for routing process makes route discovery process start whenever it received requirement, and through using route mechanism appropriately it reduces significantly route overhead at each node. The simulation results illustrate the outstanding properties of our proposed routing protocol.展开更多
Vehicular Networks (VANET) are the largest real-life paradigm of ad hoc networks which aim to ensure road safety and enhance drivers’ comfort. In VANET, the vehicles communicate or collaborate with each other and wit...Vehicular Networks (VANET) are the largest real-life paradigm of ad hoc networks which aim to ensure road safety and enhance drivers’ comfort. In VANET, the vehicles communicate or collaborate with each other and with adjacent infrastructure by exchanging significant messages, such as road accident warnings, steep-curve ahead warnings or traffic jam warnings. However, this communication and other assets involved are subject to major threats and provide numerous opportunities for attackers to launch several attacks and compromise security and privacy of vehicular users. This paper reviews the cyber security in VANET and proposes an asset-based approach for VANET security. Firstly, it identifies relevant assets in VANET. Secondly, it provides a detailed taxonomy of vulnerabilities and threats on these assets, and, lastly, it classifies the possible attacks in VANET and critically evaluates them.展开更多
Image steganography is a technique of concealing confidential information within an image without dramatically changing its outside look.Whereas vehicular ad hoc networks(VANETs),which enable vehicles to communicate w...Image steganography is a technique of concealing confidential information within an image without dramatically changing its outside look.Whereas vehicular ad hoc networks(VANETs),which enable vehicles to communicate with one another and with roadside infrastructure to enhance safety and traffic flow provide a range of value-added services,as they are an essential component of modern smart transportation systems.VANETs steganography has been suggested by many authors for secure,reliable message transfer between terminal/hope to terminal/hope and also to secure it from attack for privacy protection.This paper aims to determine whether using steganography is possible to improve data security and secrecy in VANET applications and to analyze effective steganography techniques for incorporating data into images while minimizing visual quality loss.According to simulations in literature and real-world studies,Image steganography proved to be an effectivemethod for secure communication on VANETs,even in difficult network conditions.In this research,we also explore a variety of steganography approaches for vehicular ad-hoc network transportation systems like vector embedding,statistics,spatial domain(SD),transform domain(TD),distortion,masking,and filtering.This study possibly shall help researchers to improve vehicle networks’ability to communicate securely and lay the door for innovative steganography methods.展开更多
Wireless technology is transforming the future of transportation through the development of the Internet of Vehicles(IoV).However,intricate security challenges are intertwinedwith technological progress:Vehicular ad h...Wireless technology is transforming the future of transportation through the development of the Internet of Vehicles(IoV).However,intricate security challenges are intertwinedwith technological progress:Vehicular ad hoc Networks(VANETs),a core component of IoV,face security issues,particularly the Black Hole Attack(BHA).This malicious attack disrupts the seamless flow of data and threatens the network’s overall reliability;also,BHA strategically disrupts communication pathways by dropping data packets from legitimate nodes altogether.Recognizing the importance of this challenge,we have introduced a new solution called ad hoc On-Demand Distance Vector-Reputation-based mechanism Local Outlier Factor(AODV-RL).The significance of AODVRL lies in its unique approach:it verifies and confirms the trustworthiness of network components,providing robust protection against BHA.An additional safety layer is established by implementing the Local Outlier Factor(LOF),which detects and addresses abnormal network behaviors.Rigorous testing of our solution has revealed its remarkable ability to enhance communication in VANETs.Specifically,Our experimental results achieve message delivery ratios of up to 94.25%andminimal packet loss ratios of just 0.297%.Based on our experimental results,the proposedmechanismsignificantly improves VANET communication reliability and security.These results promise a more secure and dependable future for IoV,capable of transforming transportation safety and efficiency.展开更多
基金the Iran Telecommunication Research Center (ITRC)
文摘Currently, there is a growing belief that putting an IEEE 802.11-like radio into road vehicles can help the drivers to travel more safely. Message dissemination protocols are primordial for safety vehicular applications. There are two types of safety messages which may be exchanged between vehicles: alarm and beacon. In this paper we investigate the feasibility of deploying safety applications based on beacon message dissemination through extensive simulation study and pay special attention to the safety requirements. Vehicles are supposed to issue these messages periodically to announce to other vehicles their current situation and use received messages for preventing possible unsafe situations. We evaluate the performance of a single-hop dissemination protocol while taking into account the quality of service (QoS) metrics like delivery rate and delay. We realize that reliability is the main concern in beacon message dissemination. Thus, a new metric named effective range is defined which gives us more accurate facility for evaluating QoS in safety applications specifically. Then, in order to improve the performance, the effects of three parameters including vehicle's transmission range, message transmission's interval time and message payload size are studied. Due to special characteristics of the safety applications, we model the relationship between communication-level QoS and application-level QoS and evaluate them for different classes of safety applications. As a conclusion, the current technology of IEEE 802.11 MAC layer has still some challenges for automatic safety applications but it can provide acceptable QoS to driver assistance safety applications.
文摘As Vehicular ad hoc networks (VANETs) become more sophisticated, the importance of integrating data protection and cybersecurity is increasingly evident. This paper offers a comprehensive investigation into the challenges and solutions associated with the privacy implications within VANETs, rooted in an intricate landscape of cross-jurisdictional data protection regulations. Our examination underscores the unique nature of VANETs, which, unlike other ad-hoc networks, demand heightened security and privacy considerations due to their exposure to sensitive data such as vehicle identifiers, routes, and more. Through a rigorous exploration of pseudonymization schemes, with a notable emphasis on the Density-based Location Privacy (DLP) method, we elucidate the potential to mitigate and sometimes sidestep the heavy compliance burdens associated with data protection laws. Furthermore, this paper illuminates the cybersecurity vulnerabilities inherent to VANETs, proposing robust countermeasures, including secure data transmission protocols. In synthesizing our findings, we advocate for the proactive adoption of protective mechanisms to facilitate the broader acceptance of VANET technology while concurrently addressing regulatory and cybersecurity hurdles.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2022R1A2C1003549).
文摘Wireless Ad Hoc Networks consist of devices that are wirelessly connected.Mobile Ad Hoc Networks(MANETs),Internet of Things(IoT),and Vehicular Ad Hoc Networks(VANETs)are the main domains of wireless ad hoc network.Internet is used in wireless ad hoc network.Internet is based on Transmission Control Protocol(TCP)/Internet Protocol(IP)network where clients and servers interact with each other with the help of IP in a pre-defined environment.Internet fetches data from a fixed location.Data redundancy,mobility,and location dependency are the main issues of the IP network paradigm.All these factors result in poor performance of wireless ad hoc networks.The main disadvantage of IP is that,it does not provide in-network caching.Therefore,there is a need to move towards a new network that overcomes these limitations.Named Data Network(NDN)is a network that overcomes these limitations.NDN is a project of Information-centric Network(ICN).NDN provides in-network caching which helps in fast response to user queries.Implementing NDN in wireless ad hoc network provides many benefits such as caching,mobility,scalability,security,and privacy.By considering the certainty,in this survey paper,we present a comprehensive survey on Caching Strategies in NDN-based Wireless AdHocNetwork.Various cachingmechanism-based results are also described.In the last,we also shed light on the challenges and future directions of this promising field to provide a clear understanding of what caching-related problems exist in NDN-based wireless ad hoc networks.
文摘There is a significant increase in the rates of vehicle accidents in countries around the world and also the casualties involved ever year. New technologies have been explored relating to the Vehicular Ad Hoc Network (VANET) due to the increase in vehicular traffic/congestions around us. Vehicular communication is very important as technology has evolved. The research of VANET and development of proposed systems and implementation would increase safety among road users and improve the comfort for the corresponding passengers, drivers and also other road users, and a great improvement in the traffic efficiency would be achieved. This research paper investigates the current and existing security issues associated with the VANET and exposes any slack amongst them in order to lighten possible problem domains in this field.
基金supported by National Science Fund for Distinguished Young Scholars (No.60525110)National 973 Program (No. 2007CB307100, 2007CB307103)+2 种基金National Natural Science Foundation of China (No. 60902051)Chinese Universities Scientific Fund (BUP-T2009RC0505)Development Fund Project for Electronic and Information Industry (Mobile Service and Application System Based on 3G)
文摘In this paper we analyze connectivity of one-dimensional Vehicular Ad Hoc Networks where vehicle gap distribution can be approximated by an exponential distribution. The probabilities of Vehicular Ad Hoc Network connectivity for difference cases are derived. Furthermore we proof that the nodes in a sub-interval [z1,z1 +Δz] of interval [0, z], z>0 where all the nodes are independently uniform distributed is a Poisson process and the relationship of Vehicle Ad hoc Networks and one-dimensional Ad Hoc networks where nodes independently uniform distributed in [z1,z1 +Δz] is explained. The analysis is validated by computing the probability of network connectivity and comparing it with the Mont Carlo simulation results.
文摘Vehicular Ad hoc Networks(VANETs)become a very crucial addition in the Intelligent Transportation System(ITS).It is challenging for a VANET system to provide security services and parallelly maintain high throughput by utilizing limited resources.To overcome these challenges,we propose a blockchain-based Secured Cluster-based MAC(SCB-MAC)protocol.The nearby vehicles heading towards the same direction will form a cluster and each of the clusters has its blockchain to store and distribute the safety messages.The message which contains emergency information and requires Strict Delay Requirement(SDR)for transmission are called safety messages(SM).Cluster Members(CMs)sign SMs with their private keys while sending them to the blockchain to confirm authentication,integrity,and confidentiality of the message.A Certificate Authority(CA)is responsible for physical verification,key generation,and privacy preservation of the vehicles.We implemented a test scenario as proof of concept and tested the safety message transmission(SMT)protocol in a real-world platform.Computational and storage overhead analysis shows that the proposed protocol for SMT implements security,authentication,integrity,robustness,non-repudiation,etc.while maintaining the SDR.Messages that are less important compared to the SMs are called non-safety messages(NSM)and vehicles use RTS/CTS mechanism for NSM transmission.Numerical studies show that the proposed NSM transmission method maintains 6 times more throughput,2 times less delay and 125%less Packet Dropping Rate(PDR)than traditional MAC protocols.These results prove that the proposed protocol outperforms the traditional MAC protocols.
文摘In this paper, we present an analytical model to determine the network connectivity probability of a linear vehicular ad hoc network (VANET) formed by communication equipped vehicles on a two-way street scenario. We consider the highway to be consisting of two lanes with vehicles moving in both directions on these lanes and focus on the probability of being able to convey messages from a source vehicle to a destination vehicle, which may be multiple hops away. Closed form analytical expression is obtained for the network connectivity probability in the presence of Nakagami fading channel. In our model, the transmission range of each vehicle is modeled as a random variable due to channel fading. The analytical results are validated by extensive simulations.
基金partially supported by The National Key Research and Development Program of China(No.2016YFB0200404)National Natural Science Foundation of China(No.61501527,61379157,U1711263)+6 种基金MOE-CMCC Joint Research Fund of China(No.MCM20160104)State’s Key Project of Research and Development Plan(No.2016YFE01229003)the Fundamental Research Funds for the Central Universitiesthe Science,Technology and Innovation Commission of Shenzhen Municipality(JCYJ20160429170032960)Guangdong Science and Technology Project(No.2016B010126003)2016 Major Project of Collaborative Innovation in Guangzhou(No.201604046008)Program of Science and Technology of Guangdong(No.2015B010111001)
文摘Due to high node mobility, stability has been always one of the major concerns of vehicle clustering algorithms in vehicular ad hoc networks. In this paper, we propose a novel clustering algorithm based on the information of routes planned by vehicular navigation systems. In the clustering algorithm, we design a residual route time function to quantitatively calculate the overlapping time among vehicles based on route information, with which a novel clusterhead selection metric is presented. We further design a mechanism of future-clusterhead, which can help avoid message exchanges at intersections and reduce the overhead of cluster maintenance. The simulation results show that, compared with previous works, our clustering algorithm can achieve higher stability and at the same time lower communication cost.
基金Supported by the National Basic Research Program of China (No. 2006CB303000)the National Natural Science Foundation of China (No. 60773091, F020303).
文摘This paper studies a routing protocol used in the application of collecting real-time traffic informationusing mobile vehicles to monitor traffic status. The biggest challenge of vehicular ad hoc network routingprotocol lies in the mismatch between the direction of moving vehicles and routed data. In order to dealwith this mismatch, a mesh based routing protocol with a two-tier network architecture is proposed. Byusing mesh nodes deployed at intersections, data can be routed through an optimized path which can improvethe delivery ratio and reduce the consumption of network resources. The simulation uses the mobilitymodel processed from the GPS data of taxis running in Shanghai urban areas. The result shows that theproposed protocol outperforms the existing flooding protocol.
基金Chinese National High Technology Research and Development Program(No.2014BAG03B03)
文摘With the rapid development of vehicular ad hoc network( VANET) technology,VANET applications such as safe driving and emergency rescue demand high position accuracy,but traditional GPS is difficult to meet new accuracy requirements. To overcome this limitation,a new vehicle positioning method based on radio frequency identification( RFID) is proposed. First RFID base stations are divided into three categories using fuzzy technology,and then Chan algorithm is used to calculate three vehicles' positions,which are weighed to acquire vehicles' accurate position. This method can effectively overcome the problem that vehicle positioning accuracy is not high resulting from the factors such as ambient noise and base distribution when Chan algorithm is used. Experimental results show that the performance of the proposed method is superior to Chan algorithm and 2-step algorithm based on averaging method,which can satisfy the requirements of vehicle positioning in VANETs.
基金Supported by the National Natural Science Foundation of China (No. 60873192,61070182)
文摘In this paper,we investigate the connectivity of vehicular ad hoc networks in free-flow traffic situationwith channel randomness.In order to illustrate the realistic environment,we consider that vehiclesare distributed in free-flow highway according to a Poisson point process,and signal propagation betweenconnected vehicles is subjected to log-normal shadowing effects.We obtain the distribution of the spaceheadway between successive vehicles and the distribution of signal coverage,which allows us to use theequivalent M/G/∞ queue theory to model the connectivity of VANETs in the form of average broadcastpercolation distance and average number of connected nodes.Then,extensive simulation studies are conductedto evaluate the obtained results.The analytical model presented here is able to describe the impactof various system parameters,including traffic parameters and signal propagation parameters on the connectivity.We use our analytical results,along with the common signal propagation data,to understandimpact of channel randomness on the connectivity of VANETs.
基金Supported by the National Natural Science Foundation of China (No. 60502028)the Youth Chenguang Project of Science and Technology of Wuhan City of China (No. 200750731252)the Natural Science Foundation of Hubei Province of China (No. 2007ABA324)
文摘The problem of information dissemination is researched for vehicular ad-hoc networks(VANET)inthis paper,and a contention-based efficient-information perception algorithm(CEiPA)is proposed.Theidea of CEiPA is that beacons are delivered over VANET with limited lifetime and efficient information.CEiPA consists of two phases.The first one is initialization phase,during which the count timers T_(cycle)and T_(local)are set to start beacon delivery while T_(cycle)is also used to monitor and restart beaconing.Thesecond one is beacon delivery phase.An elaborate distance function is employed to set contention delayfor beacons of each vehicle.In this way beacons will be sent in order,which decreases the collision ofbeacons.Simulation results show that CEiPA enables each beacon to carry more efficient information andspread them over more vehicles with lower network overhead than the periodic beacon scheme.CEiPA isalso flexible and scalable because the efficient information threshold it employs is a balance among thefreshness of information,network overhead and perception area of a vehicle.
文摘In vehicular ad-hoc networks (VANETs), store-carry-forward approach may be used for data sharing, where moving vehicles carry and exchange data when they go by each other. In this approach, storage resource in a vehicle is generally limited. Therefore, attributes of data that have to be stored in vehicles are an important factor in order to efficiently distribute desired data. In VANETs, there are different types of data which depend on the time and location. Such kind of data cannot be deployed adequately to the requesting vehicles only by popularity-based rule. In this paper, we propose a data distribution method that takes into account the effective life and area in addition to popularity of data. Our extensive simulation results demonstrate drastic improvements on acquisition performance of the time and area specific data.
文摘This work proposes authentication based on identity as a way to increase the efficiency and security of communications in vehicular ad-hoc networks. When using identity-based cryptography to achieve certificateless authentication, membership revocation is not a trivial problem. Thus, in order to improve the performance of revocation in such networks, the use of a dynamic authenticated data structure based on perfect k-ary hash trees combined with a duplex version of the new standard SHA-3 is here presented. Efficient algorithms in the used revocation trees allow reaching a refresh rate of at most simple updates per inserted node. Consequently, the proposal is especially useful for situations with frequent revocations, which are foreseeable when vehicular ad- hoc networks are widely deployed.
基金partially supported by National Key Research and Development Program of China(2016YFB0200400)National Natural Science Foundation of China(No.61379157)+1 种基金Program of Science and Technology of Guangdong(No.2015B010111001)MOE-CMCC Joint Research Fund of China(No.MCM20160104)
文摘This paper comes up with a SDN Based Vehicle Ad-Hoc On-Demand Routing Protocol(SVAO),which separates the data forwarding layer and network control layer,as in software defined networking(SDN),to enhance data transmission efficiency within vehicle ad-hoc networks(VANETs).The roadside service unit plays the role of local controller and is in charge of selecting vehicles to forward packets within a road segment.All the vehicles state in the road.Correspondingly,a two-level design is used.The global level is distributed and adopts a ranked query scheme to collect vehicle information and determine the road segments along which a message should be forwarded.On the other hand,the local level is in charge of selecting forwarding vehicles in each road segment determined by the global level.We implement two routing algorithms of SVAO,and compare their performance in our simulation.We compare SVAO with popular ad-hoc network routing protocols,including Optimized Link State Routing(OLSR),Dynamic Source Routing(DSR),Destination Sequence Distance Vector(DSDV),and distance-based routing protocol(DB)via simulations.We consider the impact of vehicle density,speed on data transmission rate and average packet delay.The simulation results show that SVAO performs better than the others in large-scale networks or with high vehicle speeds.
基金Sponsored by the National Science and Technology Major Project(Grant No. 2010ZX03005-003)
文摘Due to highly dynamic topology caused by fast moving nodes the Vehicular ad-hoc network (VANET) results in the existence of transient communication links, which degrade the performance of developed protocols. Established routes frequently become stale, and existing communication flows are interrupted, incurring delay and additional overhead. In this paper we propose a novel hybrid routing protocol, which is the combined between of the table-driven routing and on-demand routing in VANET. It makes fast convergence in routing process, minimal drop links, making more reliable links, and adaptive with changing of VANET topology. With neighbor table is updated instantaneously, and using strong neighbor for routing process makes route discovery process start whenever it received requirement, and through using route mechanism appropriately it reduces significantly route overhead at each node. The simulation results illustrate the outstanding properties of our proposed routing protocol.
文摘Vehicular Networks (VANET) are the largest real-life paradigm of ad hoc networks which aim to ensure road safety and enhance drivers’ comfort. In VANET, the vehicles communicate or collaborate with each other and with adjacent infrastructure by exchanging significant messages, such as road accident warnings, steep-curve ahead warnings or traffic jam warnings. However, this communication and other assets involved are subject to major threats and provide numerous opportunities for attackers to launch several attacks and compromise security and privacy of vehicular users. This paper reviews the cyber security in VANET and proposes an asset-based approach for VANET security. Firstly, it identifies relevant assets in VANET. Secondly, it provides a detailed taxonomy of vulnerabilities and threats on these assets, and, lastly, it classifies the possible attacks in VANET and critically evaluates them.
基金Dr.Arshiya Sajid Ansari would like to thank the Deanship of Scientific Research at Majmaah University for supporting this work under Project No.R-2023-910.
文摘Image steganography is a technique of concealing confidential information within an image without dramatically changing its outside look.Whereas vehicular ad hoc networks(VANETs),which enable vehicles to communicate with one another and with roadside infrastructure to enhance safety and traffic flow provide a range of value-added services,as they are an essential component of modern smart transportation systems.VANETs steganography has been suggested by many authors for secure,reliable message transfer between terminal/hope to terminal/hope and also to secure it from attack for privacy protection.This paper aims to determine whether using steganography is possible to improve data security and secrecy in VANET applications and to analyze effective steganography techniques for incorporating data into images while minimizing visual quality loss.According to simulations in literature and real-world studies,Image steganography proved to be an effectivemethod for secure communication on VANETs,even in difficult network conditions.In this research,we also explore a variety of steganography approaches for vehicular ad-hoc network transportation systems like vector embedding,statistics,spatial domain(SD),transform domain(TD),distortion,masking,and filtering.This study possibly shall help researchers to improve vehicle networks’ability to communicate securely and lay the door for innovative steganography methods.
文摘Wireless technology is transforming the future of transportation through the development of the Internet of Vehicles(IoV).However,intricate security challenges are intertwinedwith technological progress:Vehicular ad hoc Networks(VANETs),a core component of IoV,face security issues,particularly the Black Hole Attack(BHA).This malicious attack disrupts the seamless flow of data and threatens the network’s overall reliability;also,BHA strategically disrupts communication pathways by dropping data packets from legitimate nodes altogether.Recognizing the importance of this challenge,we have introduced a new solution called ad hoc On-Demand Distance Vector-Reputation-based mechanism Local Outlier Factor(AODV-RL).The significance of AODVRL lies in its unique approach:it verifies and confirms the trustworthiness of network components,providing robust protection against BHA.An additional safety layer is established by implementing the Local Outlier Factor(LOF),which detects and addresses abnormal network behaviors.Rigorous testing of our solution has revealed its remarkable ability to enhance communication in VANETs.Specifically,Our experimental results achieve message delivery ratios of up to 94.25%andminimal packet loss ratios of just 0.297%.Based on our experimental results,the proposedmechanismsignificantly improves VANET communication reliability and security.These results promise a more secure and dependable future for IoV,capable of transforming transportation safety and efficiency.