Vehicular Ad Hoc Networks Essay Example for Free

vehicular Ad Hoc Networks EssayABSTRACT.Vehicular Ad Hoc Networks is a kind of special wireless ad hoc mesh, which has the characteristics of high node mobility and fast analysis situs changes. The Vehicular Networks can provide wide variety of services, ranges from safety and crash avoidance to internet entre and multimedia applications. Attacking and misusing such web could wee destructive consequences. It is therefore necessary to integrate certificate fates into the chassis of VANETs and defend VANET administrations against misdeed, in order to ensure correct and smooth operations of the network. In this paper, I propose a security body for VANETs to achieve privacy desired by vehicles and key faculty compulsory by law enforcement authorities, in addition to satisfying thorough security requirements including au sotication, nonrepudiation, message integrity, and confidentiality. Moreover, we propose a privacy-preserving defence reaction technique for network aut horities to handle misbehaviour in VANET access, considering the challenge that privacy provides avenue for misbehaviour. The proposed system employs an identitybased cryptosystem where certificates argon non needed for authentication. I show the fulfilment and feasibility of our system with respect to the security goals and efficiency.1 INTRODUCTION VEHICULARad hoc networks (VANETs) are receiving increasing attentions from academic and deployment efforts from industry, due to the various applications and potential tremendous benefits they offer for future VANET users. Safety culture exchange enables life-critical applications, such as the alerting functionality during hybridizing traversing and lane merging, and thus, plays a expose role in VANET applications. Valueadded services can enhance drivers traveling experience by providing convenient Internet access, navigation, toll recompense services, etc.Other applications are also possible including different warning messages for congestion avoidance, detour notification, road conditions (e.g., slippery), etc., and alarm signals disseminated by emergency vehicles (e.g., ambulance) for road clearance. The gentle features of VANETs inevitably incur higher risksif such networks do not take security into account prior to deployment. For instance, if the safety messages are modified, discarded, or delayed every intentionally or due to hardware malfunctioning, serious consequences such as injuries and even deaths may occur. This necessitates and urges the development of a functional, reliable, and efficientsecurity architecture to begin with all new(prenominal) implementation aspects of VANETs.Fundamentally,VANET security design should guarantee authentication, nonrepudiation, integrity, and in some specific application scenarios, confidentiality, to protect the network against attackers.Besides the fundamental security requirements, sensitive information such as identity and location privacy should be res erved from the vehicle proprietors perspective, against unlawful ghost and user profiling, since otherwise it is tricky to attract vehicles to join the network. On the contrary, castability is required where the identity information need be revealed by law enforcement authorities for liability issues, once accidents or crimes occur. In addition, privilege repeal is required by network authorities (e.g., network administrator) once misbehaviour is detected during network access. It is less nasty to prevent misbehavior of unauthorized users (i.e., outsiders)since legitimate users and roadside units (RSUs) can simply disregard communication requests from outsiders by means of authentication.Nevertheless, misbehaviour of legitimate users of VANETs (i.e., insiders) is more difficult and complex to prevent, the reason being that insiders possess credentials issued by the berth to perform authentication with peer vehicles or RSUs who canbeeasily tricked into trusting the insiders. C onsequently, the insiders misbehaviour impart slang much larger impact on the network and will be the focus of this paper. I proposed system in this paper and m either young proposals on VANET security provide the option of using anonymous credentials in authentication, rendering it even more complex to handle misbehaviour in VANETs, since the user identity is hidden and cannot be linked arbitrarily which curbs the punishment of misbehaving users. Contributions. Given the conflicting goals of privacy and traceability, and the challenges in designing a privacy-preserving defending team schema for VANETs,i motivated to propose a security system that can effectively and efficiently solve the conflicts and challenges.Specifically, my main contributions in this paper include 1. I propose a pseudonym-based intention to assure vehicle user privacy and traceability. 2. I design a wand spot-based scheme to achieve nonframeability in tracing law violators. In this scheme, an innocent vehicle cannot be framed by a corrupted law enforcement authority due to rolesplitting mechanism.3. A novel privacy-preserving defense scheme is proposed leveraging scepter authentication. It guarantees that any additional authentication beyond the threshold will result in the revocation of the misbehaving users. This defense scheme differs from others in the first place in that it yields flexibility in the revocation (i.e., not all types of misbehaviour should be punished). Moreover, the dynamic accumulators in the threshold authentication technique facilitates each user to place further restrictions (besides the threshold) on other communicating users, which is an attractive feature to service providers. 4. My design incorporates mechanisms that guarantee authentication, nonrepudiation, message integrity, and confidentiality.2 RELATED WORK at that place is a large body of research work related to the security and privacy in VANETs. The most related works are on the design of pr ivacypreserving schemes. Raya and Hubaux 1investigated the privacy issue by proposing a pseudonym-based approach using anonymous public keys and the public key bag (PKI), where the public key certificate is needed, with child(p) rise to extra communication and entrepot overhead. Theauthors also proposed three credential revocation protocols tailored for VANETs, namely RTPD,RC2RL, and DRP 5, considering that the certificate revocation list (CRL) needs to be distributed across the entire network in a timely manner. All the three protocols seem to work well under conventional public key infrastructure (PKI). However, the authors also proposed to use frequently updated anonymous public keys to fulfillusers requirement on identity and location privacy. If this privacy preserving technique is used in jointure with RC2RL and DRP, the CRL produced by the trusted authority will become huge in size, rendering the revocation protocols highly inefficient.A lightweight symmetric-key-based se curity scheme for equilibrateauditability and privacy in VANETs is proposed in 2. It bears the drawback that peer vehicles authenticate each other via a base station, which is unsui turn off for inter vehicle communications. Gamage et al. 6 adopted an identity-based (IDbased) ring signature scheme to achieve signer ambiguity and hence fulfill the privacy requirement in VANET applications. The disadvantage of the ring signature scheme in the mise en scene of VANET applications, is the unconditional privacy, resulting in the traceability requirement unattainable. Group signature-based schemes are proposed in 4 where signer privacy is conditional on the meeting manager. As a result, all these schemes have the problem of identity escrow, as a sort out manager who possesses the group master key can arbitrarily reveal the identity of any group member. In addition, due to the limitation of group formation in VANETs (e.g., too few cars in the vicinity to strengthen the group), the grou p-based schemes 4may not be applied appropriately.The preference of group leader will sometimes encounter difficulties since a trusted entity cannot be found amongst peer vehicles. There are also a cast of defense techniques against misbehaviour in VANET literature besides those in 1. An indirect approach via the aid of infrastructure is used in 4.The TA distributes the CRL to the infrastructure points which then take over the TAs responsibility to execute the revocation protocol. The advantage of this approach is that vehicles never need to download the entire RL. Unfortunately, the conditional anonymity claimed in 4. only applies to amongst peer vehicles, under the assumption that the infrastructure points are trusted.The infrastructure points can reveal the identity of any vehicle at any time even if the vehicle is honest. Recently, Tsang et al. 7proposed a blacklistable anonymous credential system for blocking misbehavior without the trusted third party (TTP).The blacklisting technique can be applied to VANETs as if the vehicle fails to prove that it is not on the blacklist of the currentauthenticator, the authenticator will ignore the messages or requests sent by this vehicle. Although not proposed specifically for VANETs, the proposal in 7 has a similar claim as the capability of a TTP (network authority in this paper) to recover a users identity in any case is too strong a punishment and highly undesirable in some scenarios.The downside of thistechnique is the lack of options to trace misbehaving users, since any user in the system(misbehaving or not)will by no means be place by any entity including the authorities. I proposed a privacy-preserving defense scheme against misbehavior in 8 leveraging threshold authentication technique. This scheme and the scheme in 3 both preserve user privacy, and simultaneously provide trace ability (i.e., tracing law violators by enforcement authorities in 3 and tracing misbehaving users by network authorities in 8). The major differences between these schemes are the different adept realizations of the privacy and traceability schemes, due to the different application 3 SYSTEM MODEL We describe the functionalities of our security system and define security requirements in this section. 3.1 Overview Major entities in a VANET environment are depicted in A VANET system diagram.As mentioned before, traceability is needed by law enforcement authorities (LEAs) who require the identity of a violating vehicle to be disclosed for investigating the cause of accidents or crimes. Due to the seriousness of liability issues, if a single authority (e.g., the police) is fully capable of uncover the vehicle identity, this privilege may be abused. It is desirable if two or more authorities (e.g., the police, judge, special agents, and other possible law enforcement authorities) are give distributed control over the identity retrieval process. One benefit in doing so is that corrupted authorities (the number being less than the threshold) cannot arbitrarily trace vehicle users to compromise their privacy. Another benefit is that malicious authorities cannot falsely accuse (or frame) honest users. Such role-splitting is not required for network authorities since the threshold authentication technique in our defense scheme prevents a network authority from falsely accusing honest users.The proposed security system primarily consists of techniques addressing the privacy, traceability, nonframeability, and revocation (only by network authorities) issues. Thelogic diagram of the entities interactions is depicted in logic diagram, where the arrowed lines indicate the direction of packet flow or physical communications, the bracketed numbers airless each line index the major events or roles between the connected entities. The vehicle users are split into access group owners and members, whereas the RSUs can only be accessgroup owners. The entities and events/ operations are described in what follows.3.2 Entities and Procedures The entities in this system are the regional transportation authorities (RTAs), law enforcement authorities (LEAs),network authorities, roadside infrastructure including border RSUs for pseudonym management and regular RSUs (simply RSUs) for Internet access, and vehicle users. Considering practical scenarios, the RSUs in this system are mainly responsible for providing infrastructure access and network services. The RSUs are assumed to be operated by third-party service providers (SPs) who have business contracts with the RTA to build access infrastructure in the RTAs region. The RSUs are thus not owned by the RTA and have no preestablished trust relationship with the RTA. On the other hand, borders RSUs are owned and operated by the RTA, and can be considered as the agents who are delegated with the RTAs authority.These entities are involved in the following proceduremay be caused by malfunctioning hardware and thus is incidental. These types of misbehavior share a common feature, i.e., their occurrence or frequency is low, specifically, lower than a predetermined threshold. Threshold authentication-based defense further consists of six sub-procedures Membership registration RSUs and vehicle users registry with the RTA to use VANETs. Upon successful registration, a member public/private key partner off (mpkmsk) is issued to each RSU and vehicles. The RTA associates the members credential with the issued public key and includes this pair of information into a credential list IDlist. Access group setup RSUs and vehicles setup their own access groups, the member of which is granted privilege to communicate with the access group owner. The group owner adds members to the group and updates related public information.Each added member obtains an access key mak for the group. Access group revoking The access group owner revokes the granted privilege when deciding to stop communications with a member, due to some decision criteri a for misbehaviour. The access group owner removes the member from the access group and updates related public information. Threshold authentication This procedure is executed between an RSU and a vehicle, or between peer vehicles. We call the authenticator in this procedure Alice who announces the threshold k possibly different for each user being authenticated. Theauthentication succeeds if and only if the following conditions are met simultaneously the user Bob authenticating with Alice is a registered member of the VANET system, Bob is a legitimate member of Alices access group (if Alice is an access group owner) whose member privilege has not been revoked, and the authentication threshold has not been exceeded.Alice records the authentication transcripts in AUTHlog Tracing This procedure is used by Alice to trace a misbehaving member Mn who attempts to authenticate more than k times. Alice relies on the AUTHlog and public information, and obtains Mns credential n as the procedu re yield which is reported to the RTA.Revocation/recovery Upon receiving the complaints from other entities in the system as the output of Tracing, the RTA decides if the misbehaving members credential needs to be revoked. The RTA then performs the identity recovery by looking up the same pseudonym lookup table PLT (cf.System setup above) which also records the correspondence between the credential n and identity IDn. Note that for the ease of presentation, we assume the RTAs to act as network authorities for the defense scheme in this paper. In reality, when the roles of RTA and network authoritySystem setup This procedure is executed by the RTA for initial VANET system setup including domain statement publication, public/private key assignment for entities in the system to perform desired tasks, and database creation for storing necessary records (i.e., the pseudonym lookup table PLT). Pseudonym contemporaries and authentication for privacy RTA and border RSUs execute this proce dure to assign pseudonym/private key pairs to both vehicles traveling in their home domain and vehicles from other RTAs domains, so that these vehicles are able to authenticate with RSUs and other vehicles to obtain services and useful messages.Threshold signature for nonframeability This procedure is invoked by LEAs to share the secret information for recovering a guilty vehicles identity. Meanwhile, it prevents corrupted authorities from gathering full power to accuse an innocent vehicle. The functional component of this procedure is the threshold signature. Threshold-authentication-based defense Designed for the network authorities, this procedure is used to revoke a misbehaving vehicles credential, refraining the vehicle from further disrupting system operations. As the sum total of this procedure, the threshold authenticationtechnique provides a mechanism to allow certain types of misbehavior that should not result in revocation. For instance, the misbehaviorare separate, the network authority can simply take charge as the RTA in the above sub procedures. Nonetheless, in the execution of Revocation/recovery, the network authority needs to establish trust with or be delegated by the RTA in order to access the PLT.When we mention network authorities in what follows, we implicitly refer to RTAs in the network authority role. 3.3 Security Requirements I define the security requirements for a VANET security system, and will show the fulfillment of these requirements after presenting the design details. 1. Privacy The privacy requirement states that private information such as vehicle owners identity and location privacy is preserved against unlawful tracing and user profiling. 2. Traceability It is required where the identity information of violators need be revealed by law enforcement authorities for liability purposes. The traceability requirement also indicates that a misbehaving user will be identified and the corresponding credential revoked, if necessar y, by network authorities, to prevent this user from further disrupting system operations. Certain criteria have to be met for the traceability of a misbehaving user as explained in the next section.3. Nonframeability Nonframeability requires that no entity in the system can accuse an honest user for having violated the law or misbehaved. 4. Other requirements A secure VANET system should satisfy several fundamental requirements, namely, authentication, nonrepudiation, message integrity, and confidentiality where sensitive information is being exchanged, to protect the system against unauthorized-message injection, denial of message disseminations, message alteration, and eavesdropping, respectively. Nonrepudiation also requires that violators or misbehaving users cannot get across the fact that they have violated the law or misbehaved. 4 CONCLUSIONS AND FUTURE WORK I have presented the VANET security system mainly achieving privacy, traceability, nonframeability, and privacy-prese rving defense against misbehaviour and reducing traffic in the network. These functionalities are realized by thepseudonym-based technique, the threshold signature, and the threshold authentication based defense scheme. The ID-based cryptosystem facilitatesus to design communication and storage efficient schemes. Our future work consists of simulating the proposed security system and experimenting it in real VANET settings.REFERENCES1 M. Raya and J-P. Hubaux, Securing Vehicular Ad Hoc Networks, J. Computer Security, special issue on security of ad hoc and sensor networks, vol. 15, no. 1, pp. 39-68, 2007. 2 J.Y. Choi, M. Jakobsson, and S. Wetzel, Balancing Auditability and Privacy in Vehicular Networks, Proc. First ACM Intl WorkshopQoS and Security for Wireless and Mobile Networks (Q2SWinet 05), pp. 79-87, Oct. 2005. 3 J. Sun, C. Zhang, and Y. Fang, An Id- base Framework Achieving Privacy and Non-Repudiation in Vehicular Ad Hoc Networks, Proc. IEEE Military Comm. Conf., pp. 1-7, Oct. 2007. 4 X. Lin, X. Sun, P.-H. Ho, and X. Shen, GSIS A Secure and Privacy-Preserving Protocol for Vehicular Communications,IEEE Trans. Vehicular Technology, vol. 56, no. 6, pp. 3442-3456, Nov. 2007. 5 M. Raya, P. apadimitratos, I. Aad, D. Jungels, and J.-P. Hubaux,Eviction of Misbehaving and Faulty Nodes in Vehicular Networks, IEEE J. Selected Areas Comm., vol. 25, no. 8, pp. 15571568,Oct. 2007. 6 C. Gamage, B. Gras, B. Crispo, and A.S. Tanenbaum, An Identity Based Ring Signature Scheme with Enhanced Privacy, Proc.Second Intl Conf. Security and Privacy in Comm. Networks (SecureComm 06), Aug. 2006. 7 P. Tsang, M.H. Au, A. Kapadia, and S.W. 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