VANET中隐私保护的格基异构签密方案

针对车载自组织网络(Vehicular Ad hoc Network,VANET)中车辆跨密码系统通信过程中的隐私泄露问题,提出了一种格基异构签密方案.首先,方案实现了无证书密码系统(Certificateless Cryptosystem,CLC)的车辆与基于身份密码系统(Identity-Based Cryptosystem,IBC)的车辆相互通信;其次利用签密的机密性和可认证性防止车辆用户在跨密码系统通信过程中发生隐私泄露,并实现了接收方对消息完整性以及发送方身份合法性的认证;最后在随机预言机模型下证明了方案在适应性选择密文攻击下具有不可区分性(Indistinguishability against adaptive Chosen Cipher Text Attack,IND-CCA2),在适应性选择消息攻击下具有存在性不可伪造性(Existential Unforgeability against adaptive Chosen Messages Attack,EUF-CMA).性能分析表明,与其他方案相比,本文方案在计算开销、通信开销和安全性方面具有一定优势,适用于车辆跨密码系统通信的场景.

Cybersecurity and Privacy Protection in Vehicular Networks (VANETs)

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.

A Review on the Recent Trends of Image Steganography for VANET Applications

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.

VANET随机部署环境下基于改进型共享最近邻密度峰聚类的快速分簇算法

针对车辆高速移动场景下,网络拓扑变化过大导致网络分簇结果不稳定的问题,提出一种基于改进型共享最近邻密度峰聚类的快速成簇算法SNNCA(shared nearest neighbor clustering algorithm);通过综合考虑节点的链路生存周期和移动相似性,提出一种全新的节点连接稳定程度评估指标,并将该评估指标应用于节点共享最近邻的计算过程,以组织网络节点为划分合理的多跳簇结构;为适应网络环境的动态变化,提出一种簇维护策略,其中每个层级的簇成员承担着维护下一层级簇成员的任务,该策略能够对簇成员进行批量分离或合并,从而实现了算法的分布式快速收敛;根据随机部署场景中进行的仿真实验结果显示,相比其他较新算法,SNNCA算法降低了74%的簇数量,并且簇成员的平均存活时间增加了近1倍,表现出更好的网络稳定性和健壮性。

Performance of beacon safety message dissemination in Vehicular Ad hoc NETworks (VANETs)

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.

基于区块链的VANET无证书聚合签名方案

车载自组网(VANET)中频繁的通信和海量数据交互更易泄露车辆身份、位置、行驶路线等信息,交互验证的过程中证书开销会越来越大而且更容易遭受恶意攻击。为了解决以上问题,提出了基于区块链的VANET无证书聚合签名方案,消除证书开销,使用假名保护用户身份隐私。使用椭圆曲线加密算法实现无证书聚合签名,结合区块链的分布式存储实现信息共享、道路信息透明以及对恶意参与者的追踪。搭建以太坊私有链进行仿真,利用智能合约实现访问控制和交易,实验结果表明,在实现强匿名性、不可链接性、消息完整性、不可否认、可追踪、防篡改的安全性能的同时,通信开销相比同类方案中使用双线性配对方法降低了至少85.8%。

A Combined Admission and Priority Control Mechanism for Assuring Communication Quality in VANETs integrated with Wireless Mesh Networks

In this paper, we introduce a new combined priority and admission control mechanism applying in the VCN （Vehicular Communication Network） which is designed with an integration of the Vehicular Ad-hoc Networks （VANETs） based on standard IEEE 802.11 p and IEEE 802.11 s WMNs （Wireless Mesh Networks）. Simulation experiments are intensively investigated to evaluate the novel combined priority and admission control mechanism to assure quality of the I2V （Infrastructure to Vehicle） emergency services occurred during the time video flows are being delivered between content servers and cars. The simulation results show effectiveness of proposed priority and admission control schemes in term of the minimized end-to-end delay as well as the increase of throughput and PDR （Packet Delivery Ratio） of the emergency data flow.

Review of the Security Issues in Vehicular Ad Hoc Networks (VANET)

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.

车联网隐私保护自主管理身份方案

针对车联网(VANETs)环境下车辆用户数字身份管理问题,该文提出基于区块链的去中心化可撤销隐私保护自主管理身份(SSI)方案。经可信机构(TA)授权后,路侧单元(RSU)组成委员会负责车辆用户身份注册、数字身份凭证颁发及维护。基于门限BLS签名和实用拜占庭容错(PBFT)共识机制实现数字身份凭证创建,解决凭证颁发机构去中心化问题;集成秘密共享和零知识证明技术,解决数字身份凭证颁发和验证过程中隐私保护问题;基于密码学累加器技术,解决分布式存储环境数字身份凭证撤销问题。最后,对该方案安全属性进行了详细分析,证明方案能够满足所提出的安全目标,同时基于本地以太坊私有链平台使用智能合约对所提方案进行了实现及性能分析,实验结果表明了设计的可靠性、可行性和有效性。

车联网中基于阈值的边缘辅助身份认证方案

车联网中的身份认证方案是解决车联网许多安全和隐私问题的有效途径之一。然而,现有认证方案多数没有关注单点故障问题或者存在信息泄露。针对上述问题,提出了一种车联网中基于阈值的边缘辅助身份认证方案。该方案在保护车辆真实身份信息的前提下,由多个边缘节点协同认证车辆,避免了单点故障问题。同时,在初始合作认证阶段生成令牌用于快速切换认证阶段的身份认证,在不与多个边缘节点交互下实现基于身份认证的快速切换,有效减少了认证延迟。若认证过程中出现异常,云计算中心也可以对恶意车辆进行追踪,还原其真实身份并进行撤销。安全性分析和仿真实验表明,所提方案是安全有效的。最后对提出方案进行了总结,并对未来工作作出展望。

基于区块链的车载自组网车与基础设施快速切换认证方案

针对车载自组网(VANET)中车辆通信面临的安全风险挑战以及车辆进入新的基础设施覆盖范围时需要进行复杂的身份重新认证问题,提出基于区块链的车载自组网V2I(Vehicle-to-Infrastructure)快速切换认证方案。该方案利用区块链去中心化、分布式和防篡改的特性,实现车辆认证信息的存储与查询;使用令牌机制,减少区块链查询次数,简化路边单元(RSU)切换认证阶段的认证过程,在后续的认证过程中只需检查令牌的有效性,实现了RSU的快速切换认证;采用了批量认证方法,能有效减少认证过程中的计算开销,提高消息认证效率;另外,可以实现对恶意车辆的追溯与撤销,并及时更新车辆的匿名身份,保证车辆的匿名性。相较于匿名批量认证方案、全聚合认证方案、无证书聚合签名方案、基于区块链的认证方案,所提方案在消息认证耗时上缩短了约51.1%、77.45%、77.56%和76.01%。实验结果表明,该方案能够有效降低车载自组网中的计算开销和通信开销。

基于链路预测的VANET路由算法

在车载自组织网络(VANET)中,AODV路由算法存在控制开销大、路由发现和修复时间长等不足。为此,对AODV算法进行局部优化,提出一种改进的路由算法,利用节点位置、运动速度等信息预测链路失效时间。在路由发现阶段,将链路失效时间最大的路径作为传输路径;在路由维护阶段,设置定时器并提前触发路由寻路,减少路径搜寻时间。仿真结果表明,与AODV算法相比,该算法在数据包端到端延迟、传输吞吐率及报文投递率等方面性能较好。

车载自组织网络中格基签密的可认证隐私保护方案

针对车载自组织网络(VANET)中用户的隐私泄露和信息传输过程中的安全认证问题,提出一种VANET中格基签密的可认证隐私保护方案。首先,消息发送方利用接收方的公钥对消息进行签密,只有拥有私钥的接收车辆才能解密出消息,以保证消息内容在传输过程中只对授权用户可见;其次,车辆接收方解密出消息后,利用单向安全的哈希函数计算消息的哈希值,并判断是否与签密过程中的哈希值相等,实现对消息的认证;最后,采用快速数论变换(NTT)算法降低格中环上多项式乘法的计算开销,提高方案的计算效率。在随机预言机模型下证明了所提方案在适应性选择密文攻击下具有不可区分性,在适应性选择消息攻击(IND-CCA2)下具有强不可伪造性。此外,所提方案的安全性基于格上困难问题,可以抵抗量子算法攻击。仿真实验结果表明,与同类具有消息认证功能的隐私保护方案以及基于格上困难问题的签名方案相比,所提方案的通信时延至少减少了10.01%,消息丢失率至少减小了31.79%,通信开销至少减少了31.25%。因此,所提方案更适用于资源有限的VANET环境。

VANET中安全信息的快速可靠广播路由算法

为了满足VANET中交通安全信息实时可靠传输的需求,文中提出了一种基于自适应认证重传机制的多跳广播路由算法(ACR-BA).首先,为了节省网络资源,ACR-BA算法设计了两种短控制包,有效地抑制了传输冗余;其次,为了降低竞争信道的碰撞概率,基于地理位置划分了候选节点集,并结合控制包认证机制在一个候选节点集中仅确定出唯一的转发节点;然后,根据网络负载状况设计了一种基于单位基准时隙的自适应机制,设置尽量小的退避等待时间,提高信息广播的实时性;最后,设置了针对短控制包和数据包的超时重传保障机制,在保证算法实时性的基础上最大限度地提高可靠性.理论分析和仿真结果表明,与传统洪泛算法和时隙1坚持算法相比,ACR-BA算法有效地降低了网络中的冗余数据量,在实时性和可靠性两方面均有较大的性能提高.

面向VANET的声誉模型研究

车载自组织网络是一个典型的开放式分布系统,其网络构成具有高度动态性和很强的临时性.这些特性导致车辆与合作节点之间缺乏相互了解与信任,并且可能面临各类攻击的威胁.针对上述问题,提出在VANET中建立面向应用的车辆节点声誉模型(简称VASRep),用于量化评估节点的声誉.VASRep充分融合车辆节点上丰富的数据类型,使得声誉数据更加准确地表现出节点的可信程度;VASRep依靠权威单元对节点进行评价的方法更好地适应高移动性的VANET环境.通过分析及仿真表明,VASRep较现有模型在性能表现、遏制更广泛类型的恶意节点攻击的能力等方面都有较大的提高.

基于速度向量的VANET位置预测路由协议

针对车辆自组网(VANET)中车辆快速移动引起的网络拓扑快速变化及路由路径频繁切换引起的网络性能下降问题,提出一种适用于城市环境的基于速度向量的位置预测路由协议(VPRP)。该协议根据行驶方向将车辆分组,根据速度和当前位置预测下一步位置,选择路径中所有节点总的方向差异最小且总的距离变化最小的路径作为路由路径。仿真实验结果表明,VPRP比AODV和VHRP在吞吐量、分组投递率、平均传输延迟、控制开销等方面均有改进。

VANET场景下的GPSR-R路由算法

路由选择是实现VANET的关键技术之一,没有合适而高效的路由选择算法,VANET就无法工作。由于路由在长距离通信时多跳易断裂,通信链路只需满足通信需求即可。文章对GPSR路由协议进行了改进,提出了VANET场景下的GPSR路由算法:GPSR-R。GPSR-R根据移动节点间链路建立的网络需求进行综合考虑,充分利用不稳定但满足需求的路由完成信息的传递。分析结果表明,GPSR-R在数据包传递率、丢包率方面优于GPSR和GPSR-AD。

VANETs路由综述

针对车载自组织网络拓扑结构高动态性,阐述了路由协议研究的重要性;分析并比较了在车载自组织网络中各种路由协议的优缺点,并将现有的路由协议分为基于连通的、基于移动的、基于基础设施的、基于概率的以及基于地理位置的路由五类;根据每一类路由分析其研究现状及特性;最后展望了车载自组织网络路由技术的未来研究方向。

一种解决VANETs空洞问题的限时携带贪婪前传方法

针对车辆节点快速移动和非均匀分布导致的车联网网络空洞问题,以及空洞节点采用SCF(store carry forward)方法长期携带过时交通信息导致浪费存储资源的问题,提出一种先应式空洞发现策略以及一种限时携带的贪婪前传广播(CGFB,limited time carry and greedy forward broadcast)方法.CGFB结合了GF(greedy forward)算法和SCF算法的优点,可以提高建立路径的成功概率并降低存储消耗.仿真结果表明,当平均邻居节点数大于4时,CGFB算法成功建立路径的概率可达97%以上;相比SCF算法,当平均邻居节点数为2时,可节省90%以上的存储资源.

车载移动通信网(VANET)物理层安全问题

基于Ad Hoc网络的车载移动通信网(VANET)由于网络基础的原因,以及VANET自身的特点,带来了很多安全的问题。根据VANET的特点,对VANET进行自顶向下的分层,并针对物理层的攻击进行总结和归纳,再利用现有技术对其中一些攻击给出应对措施。底层的物理层安全的保证对整个VANET的安全至关重要。