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1.
In most safety applications within vehicle ad-hoc networks (VANETs), vehicles need to periodically broadcast messages with information of their precise positions to others. These broadcast messages, however, make it easy to track vehicles and will likely lead to violations of personal privacy. Unfortunately, most of the current location privacy enhancement methodologies in VANETs suffer some shortcomings and do not take driving safety into consideration. In this paper, we propose a safe distance based location privacy scheme called SafeAnon, which can significantly enhance location privacy as well as traffic safety. By simulating vehicular mobility in a cropped Manhattan map, we evaluate the performance of the proposed scheme under various conditions. The mean entropy, warning broadcast ratio, and mean silent period of SafeAnon scheme are increasing 58%, 281%, and 50% respectively than the random silent period (RSP) scheme. The total broadcast ratio is also 33% less than that in the RSP scheme.  相似文献   

2.
李国建  陈莹 《通信技术》2015,48(7):855-859
随着车联网的发展,车辆通信将在提高行车安全,驾驶效率和舒适度方面发挥重要作用。车辆将访问多种应用,考虑到现有行车安全应用面临的严峻威胁,加之对用户验证、授权和计费的需求,攻击防护安全对于车载自组网来说尤为重要。在车辆使用基于位置的服务或行车安全服务时,攻击者可能会窃听通信内容,获取用户身份信息和位置隐私。为了提高车载自组织网安全,提出了一种采用分布式车辆公钥基础设施(VPKI)对车辆通信安全、位置隐私和身份匿名进行保护的方案。该方案采用票据为应用服务提供匿名访问控制和认证,并且可以解析和撤销不法车辆身份。最后,通过实验分析方案的效率来证明VPKI的可实施性。  相似文献   

3.
Vehicular Ad Hoc Network (VANET) has been a hot topic in the past few years. Compared with vehicular networks where vehicles are densely distributed, sparse VANET have more realistic significance. The first challenge of a sparse VANET system is that the network suffers from frequent disconnections. The second challenge is to adapt the transmission route to the dynamic mobility pattern of the vehicles. Also, some infrastructural requirements are hard to meet when deploying a VANET widely. Facing these challenges, we devise an infrastructure‐less unmanned aerial vehicle (UAV) assisted VANET system called V ehicle‐D rone hybrid vehicular ad hoc Net work (VDNet), which utilizes UAVs, particularly quadrotor drones, to boost vehicle‐to‐vehicle data message transmission under instructions conducted by our distributed vehicle location prediction algorithm. VDNet takes the geographic information into consideration. Vehicles in VDNet observe the location information of other vehicles to construct a transmission route and predict the location of a destination vehicle. Some vehicles in VDNet equips an on‐board UAV, which can deliver data message directly to destination, relay messages in a multi‐hop route, and collect location information while flying above the traffic. The performance evaluation shows that VDNet achieves high efficiency and low end‐to‐end delay with controlled communication overhead. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

4.
Advances in mobile networks and positioning technologies have made location information a valuable asset in vehicular ad-hoc networks (VANETs). However, the availability of such information must be weighted against the potential for abuse. In this paper, we investigate the problem of alleviating unauthorized tracking of target vehicles by adversaries in VANETs. We propose a vehicle density-based location privacy (DLP) scheme which can provide location privacy by utilizing the neighboring vehicle density as a threshold to change the pseudonyms. We derive the delay distribution and the average total delay of a vehicle within a density zone. Given the delay information, an adversary may still be available to track the target vehicle by some selection rules. We investigate the effectiveness of DLP based on extensive simulation study. Simulation results show that the probability of successful location tracking of a target vehicle by an adversary is inversely proportional to both the traffic arrival rate and the variance of vehicles’ speed. Our proposed DLP scheme also has a better performance than both Mix-Zone scheme and AMOEBA with random silent period.  相似文献   

5.
Service-oriented vehicular networks support diverse infrastructure-based commercial services including Internet access, real-time traffic concerns, video streaming, and content distribution. The success of service delivery in vehicular networks depends on the underlying communication system to enable the user devices to connect to a large number of communicating peers and even to the Internet. This poses many new research challenges, especially in the aspects of security, user privacy, and billing. In this article we first identify the key requirements of authentication, privacy preservation, and billing for service delivery in vehicular networks. We then review the existing industrial and academic efforts on service- oriented vehicular networks. We also point out two security challenges, minimizing vehicleto- infrastructure authentication latency and distributed public key revocation, which are considered among the most challenging design objectives in service-oriented vehicular networks. A novel fast vehicle-to-infrastructure authentication based on a vehicle mobility prediction scheme and an infrastructure-based short-time certificate management scheme are then proposed to address these two challenges.  相似文献   

6.
Data aggregation is used to combine correlated data items from different vehicles before redistributing to other vehicles in the vehicular ad hoc networks (VANET). The number of retransmissions and the communication overhead can be reduced considerably by using aggregation. It is a prerequisite for applications that require periodic dissemination of information into a large region so that, drivers can be informed well in advance and can take alternative route in case of traffic congestion. Dissemination of information to vehicles through broadcasting creates a broadcast storm problem in VANET. In this paper a novel framework is proposed for handling the local broadcast storm problem using probabilistic data aggregation which reduces the bandwidth consumption and hence improves the information dissemination. This system exploits the knowledge base and stores the decisions for aggregation and is based on a flexible and extensible set of criteria. These criteria’s can be application specific and can enable a dynamic fragmentation of the road according to the various application requirements. The framework is evaluated for VANET based traffic information system through simulation for strictly limited bandwidth and local broadcast problem. The results demonstrate that completely structure-free probabilistic data aggregation reduces the bandwidth consumption by eliminating the local broadcast problem.  相似文献   

7.
To solve the problem of security and efficiency of anonymous authentication in the vehicle Ad-hoc network(VANET), a conditional privacy protection authentication scheme for vehicular networks is proposed based on bilinear pairings. In this scheme, the tamper-proof device in the roadside unit (RSU) is used to complete the message signature and authentication process together with the vehicle, which makes it more secure to communicate between RSU and trusted authority (TA) and faster to update system parameters and revoke the vehicle. And this is also cheaper than installing tamper-proof devices in each vehicle unit. Moreover, the scheme provide provable security proof under random oracle model (ROM), which shows that the proposed scheme can meet the security requirements such as conditional privacy, unforgeability, traceability etc. And the results of simulation experiment demonstrate that this scheme not only of achieves high efficiency, but also has low message loss rate.  相似文献   

8.
Sampath  V.  Karthik  S.  Sabitha  R. 《Wireless Personal Communications》2021,117(4):2955-2971

The seamless data delivery is essential in VANET for application such as autonomous vehicle, intelligent traffic management and for the road safety and emergency applications. The incorporation of named data networking (NDN) with VANET, intended to frame intelligent traffic flow and seamless data delivery. Such integration of vehicular ad hoc networks (VANET) with NDN is termed as vehicular named data networks (VNDN). Because of the continuous node/vehicle mobility, it is a tedious process to build constant and consistent communication between vehicles. With that concern, for enhancing the performance of VNDN and solving the issues such as frequent cluster formation on heavy loaded data transmissions, position-based adaptive clustering model (PACM) is developed. The major intention of PACM is to form clusters based on trajectory. Besides, PACM performs efficient data caching by collecting significant data from vehicles to establish consistent data communication with all nodes in the network. Efficient data caching is done with the elected cluster heads among the framed clusters based on its positions and mobility models. For handling the vehicles at higher mobility speed, mutual data caching process is also designed that makes vehicles to perform on-demand data gathering from cluster heads. Further, the model is simulated and the obtained results are compared with the existing models based on the metrics such as packet delivery ratio, mean delay, cache hit rate and mean hop distance. The comparative analysis shows that the proposed model outperforms the available techniques.

  相似文献   

9.
Existing location privacypreserving methods,without a trusted third party,cannot resist conspiracy attacks and active attacks.This paper proposes a novel solution for location based service(LBS) in vehicular ad hoc network(VANET).Firstly,the relationship among anonymity degree,expected company area and vehicle density is discussed.Then,a companion set V is set up by k neighbor vehicles.Based on secure multi-party computation,each vehicle in V can compute the centroid,not revealing its location to each other.The centroid as a cloaking location is sent to LBS provider(P)and P returns a point of interest(POI).Due to a distributed secret sharing structure,P cannot obtain the positions of non-complicity vehicles by colluding with multiple internal vehicles.To detect fake data from dishonest vehicles,zero knowledge proof is adopted.Comparing with other related methods,our solution can resist passive and active attacks from internal and external nodes.It provides strong privacy protection for LBS in VANET.  相似文献   

10.
Searching for and locating a certain destination in a vehicular ad-hoc network (VANET) are fundamental issues to ensure routing and data dissemination under high mobility and lack of fixed infrastructure. However, naive-flooding searching is too expensive and takes a considerable amount of valuable bandwidth in the network. To overcome this, GPS information of the vehicles can be exploited, which can aid searching and routing in VANETs. In this paper, we present a novel position-based searching algorithm—called Fireworks—that can be used as a location discovery algorithm in VANETs. The proposed scheme is purely reactive and has a limited usage of beacons. Fireworks algorithm provides the position of the destination vehicle without having a Location Information System infrastructure or a proactive mechanism. We show that the method is efficient and reliable while greatly reducing the searching overhead. The simulations show that the algorithm covers as many nodes as naive-flooding with less than one-fifth of the broadcast messages and with less than one-third of the Dynamic Source Routing (DSR). It also performs better than Acknowledgement-Based Broadcast Protocol (ABSM) in terms of total number of broadcast messages, node coverage speed and query success rate.  相似文献   

11.
张键红  甄伟娜  邹建成 《通信学报》2014,35(Z2):191-195
在车载自组网(VANET)中许多服务和应用需要保护数据通信的安全,为提高驾驶的安全性和舒适性,一些与交通状况有关的信息就要被周期性地广播并分享给司机,如果用户的身份和信息没有隐私和安全的保证,攻击者就会通过收集和分析交通信息追踪他们感兴趣的车辆,因此,匿名消息身份验证是VANET中不可或缺的要求。另一方面,当车辆参与纠纷事件时,证书颁发机构能够恢复车辆的真实身份。为解决车载通信这一问题,郭等人在传统方案的基础上提出一种基于椭圆曲线的变色龙散列的隐私保护验证协议。虽然此方案较之前方案具有车辆身份可追踪性和高效率性,但分析表明此方案不满足匿名性。对郭等人的方案进行安全性分析并在此基础上做出改进。  相似文献   

12.
In vehicular Ad-hoc network(VANET), many multi-hop broadcast schemes are employed to widely propagate the warning messages among vehicles and the key is to dynamically determine the optimal relay vehicle for retransmission. In order to achieve reliable and fast delivery of warning messages, this paper proposes a delay-aware and reliable broadcast protocol(DR-BP) based on transmit power control technique. First, a comprehensive model is derived to evaluate the transmission in vehicle-to-vehicle communications. This model considers the wireless channel fading, transmission delay and retransmissions characters occurring in the physical layer/medium access control(PHY/MAC) layer. Then, a local optimal relay selection mechanism based on the above model is designed. In DR-BP scheme, only the vehicle selected as the optimal relays can forward warning messages and the transmit power is time-varying. Finally, extensive simulations verify the performance of DR-BP under different traffic scenarios. Simulation results show that DR-BP outperforms the traditional slotted 1-persistence(S1P) and flooding scheme in terms of packets delivery ratio and transmission delay.  相似文献   

13.
In vehicular ad hoc networks (VANET), the medium access control (MAC) protocol was of crucial importance to provide time-critical multihop broadcast. Contemporary multihop broadcast protocols in VANET usually choose the farthest node in broadcast range as the forwarder to reduce the number of forwarding hops. However, it was demonstrated that the farthest forwarder may experience long contention delay in case of high vehicle density. An IEEE 802.11p-based multihop broadcast protocol vehicle density based forwarding (VDF) was proposed, which adaptively chose the forwarder according to the vehicle density. The evaluation results in safety warning and online game applications show that, VDF could shorten broadcast delay by achieving the proper trade-off between the contention delay and coverage speed.  相似文献   

14.
It is well recognized that security is vital for reliable operation of vehicular ad-hoc networks (VANETs). Location privacy is one of the main security challenges in VANETs, which is concerned with preventing an attacker from tracking a specific vehicle. In this paper, we propose a novel location privacy preservation scheme for VANETs using random encryption periods (REP). REP is based on a privacy preserving group communication protocol, which has a conditional full statelessness property. In addition, REP ensures that the requirements to track a vehicle are always violated. By conducting detailed analysis and simulation, REP is demonstrated to be reliable, efficient, and scalable.  相似文献   

15.
Integration of vehicular ad hoc network and fixed IP network is important to provide Internet connection and mobile data service for vehicles. However, the unique characteristics of vehicular networks, such as linear topology and constrained movements of vehicles, are not considered in the conventional mobility management schemes. Using conventional schemes, unnecessary management messages are generated and the connections to roadside-installed base stations are not fully utilized. As the results, bandwidth is wasted and data delivery ratio is not maximized. In this paper, we propose a novel mobility management scheme to integrate vehicular ad hoc network and fixed IP networks more efficiently. The proposed scheme manages mobility of vehicles based on street layout as well as the distance between vehicles and base stations. Utilizing the unique characteristics of vehicular networks, the proposed scheme has substantially less mobility management overhead and higher data delivery ratio. The proposed scheme is simulated by SUMO (a vehicular traffic simulator) and QualNet (a data network simulator). The simulation results show that the proposed scheme reduced the mobility management overhead up to 63% and improved the data delivery ratio up to 90%.  相似文献   

16.
With the development of intelligent vehicles, the research on road condition monitoring has attracted much attention in the vehicular ad hoc network (VANET). The combination of VANET, cloud computing, and fog computing provides on-demand computational resources while creating a lot of new challenges. In this paper, we propose an efficient privacy-preserving cloud-fog–based traceable road surface condition monitoring scheme. We use certificateless aggregate signcryption technology to implement multiple messages aggregation verification, which greatly saves computing resources and bandwidth. Moreover, we also use a traceable vehicle pseudo identity generated by a trace authority (TRA) to achieve identity privacy protection. To ensure the privacy of the fog and cloud server, the road condition information is reported in ciphertext format. In addition, the cloud server can perform ciphertext equivalence test operation to distinguish different road condition information of the same area without compromising the confidentiality. The ciphertext, which exceeds the set threshold, is uploaded to the blockchain. It can be stored permanently and never be tampered with or deleted. Finally, we demonstrate the correctness of the proposed scheme and show that the proposed scheme has higher efficiency.  相似文献   

17.
This paper proposes transmission power control for vehicular ad hoc network (VANET) using fuzzy system. Despite the potential advantages of VANET especially for safety and intelligent transportation system, some challenges are discovered during the implementation of VANET. Main challenges emerge because of the dynamic environment and high mobility of vehicle. Furthermore, the interference due to the shared‐spectrum usage can significantly decrease the quality of signal. Fuzzy system is implemented to control the transmission power based on the signal to interference and noise ratio (SINR) difference with the targeted value of the receiver vehicle and the interference inflicted by the transmitter vehicle. The algorithm of fuzzy power control for VANET is proposed, and the performance is evaluated through the simulations. The results of simulations show that the proposed algorithm can increase SINR of vehicles especially the vehicles with SINR value below the target. Thus, the average of SINR and the throughput of the system can be increased as well.  相似文献   

18.
To move packets among the vehicles mobility pattern of vehicles in a vehicular network performs an imperative factor for creating competent routing protocol. To reproduce the movement features of vehicles in VANET is the main purpose of the mobility model. Manhattan mobility model is conversed by a lot of researchers. Merely very limited research study is prepared on highway and freeway mobility models. In this document Cluster scheme, different routing protocols are used to the freeway mobility based vehicular architecture. The Ns2.34 simulation effect illustrates the effort of cluster scheme over different protocols and standard 802.11p. The competence of the routing protocols in the vehicular communication by means of freeway movement pattern is estimated by different network parameters.  相似文献   

19.
With the increase in user mobility the most challenging issues are data scheduling which premises its users high quality of service in the context of the interoperability for microwave access in WiMAX for vehicular ad-hoc network (VANET). There is no complete proof of existing techniques accessible to provide better quality as there is a starvation problem due to the uncertainty in decision process with imprecise data. In VANET for the sake of interest while vehicles started increasing more and more in network traffic this paper devised a two stage Optimized priority scheduling scheme known as Evolving Intuitionistic Fuzzy Priority Classifier with Bio-inspiration Based Scheduling Scheme. This work takes into account the hesitation degree of each factor for priority and the bio-inspiration based classification. Through our simulation, it is shown that the projected proposal can work to acclimatize and make competent to improve the existing VANET approaches in terms of high spectrum effectiveness and low outage probability.  相似文献   

20.
Quick and accurate message transmission is an important research topic for vehicular ad hoc networks (VANET). Most studies assume that the periodic broadcast of beacon frames between vehicles increases the safety of the driver. In particular, there has been a lot of research into broadcasting based on carrier sense multiple access with collision avoidance (CSMA/CA) algorithms for medium access. However, the CSMA/CA algorithm is not an optimum technique for the VANET system, due to the transfer delay that occurs in inducing frequent collisions on transmission signals. In this paper, we propose a collision-avoidance directional medium access (CADMA) protocol and infrastructure-utilized clustering method for VANET to support reliable data transfer. In the proposed scheme, the CADMA protocol uses non-competitive transmission methods and cluster heads (CHs) to manage access by allocating the nodes resources. In addition, the roadside unit (RSU) helps with the clustering process. The simulation results indicate that the CADMA can reduce transmission delays and the collision rate of the broadcasting signal, and have shown that the CADMA can be effectively utilized for the VANET systems.  相似文献   

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