Managing and Complementing Public Key Infrastructure for Securing Vehicular Ad Hoc Networks

Recently, vehicular ad-hoc network (VANET) has emerged as an excellent candidate to change the life style of the traveling passengers along the roads and highways in terms of improving the safety levels and providing a wide range of comfort applications. Due to the foreseen impact of VANETs on our lives, extensive attentions in industry and academia are directed towards bringing VANETs into real life and standardizing its network operation. Unfortunately, the open medium nature of wireless communications and the high-speed mobility of a large number of vehicles in VANETs pose many challenges that should be solved before deploying VANETs. It is evident that any malicious behavior of a user, such as injecting false information, modifying and replaying the disseminated messages, could be fatal to other legal users. In addition, users show prime interest in protecting their privacy. The privacy of users must be guaranteed in the sense that the privacy-related information of a vehicle should be protected to prevent an observer from revealing the real identities of the users, tracking their locations, and inferring sensitive data. From the aforementioned discussion, it is clear that security and privacy preservation are among the critical challenges for the deployment of VANETs. Public Key Infrastructure (PKI) is a well-recognized solution to secure VANETs. However, the traditional management of PKI cannot meet the security requirements of VANETs. In addition, some security services such as location privacy and fast authentication cannot be provided by the traditional PKI. Consequently, to satisfy the security and privacy requirements, it is prerequisite to elaborately design an efficient management of PKI and complementary mechanisms for PKI to achieve security and privacy preservation for practical VANETs. In this thesis, we focus on developing an efficient certificate management in PKI and designing PKI complementary mechanisms to provide security and privacy for VANETs. The accomplishments of this thesis can be briefly summarized as follows. Firstly, we propose an efficient Distributed Certificate Service (DCS) scheme for vehicular networks. The proposed scheme offers a flexible interoperability for certificate service in heterogeneous administrative authorities, and an efficient way for any On-Board Units (OBUs) to update its certificate from the available infrastructure Road-Side Units (RSUs) in a timely manner. In addition, the DCS scheme introduces an aggregate batch verification technique for authenticating certificate-based signatures, which significantly decreases the verification overhead. Secondly, we propose an Efficient Decentralized Revocation (EDR) protocol based on a novel pairing-based threshold scheme and a probabilistic key distribution technique. Because of the decentralized nature of the EDR protocol, it enables a group of legitimate vehicles to perform fast revocation of a nearby misbehaving vehicle. Consequently, the EDR protocol improves the safety levels in VANETs as it diminishes the revocation vulnerability window existing in the conventional Certificate Revocation Lists (CRLs). Finally, we propose complementing PKI with group communication to achieve location privacy and expedite message authentication. In specific, the proposed complemented PKI features the following. First, it employs a probabilistic key distribution to establish a shared secret group key between non-revoked OBUs. Second, it uses the shared secret group key to perform expedite message authentication (EMAP) which replaces the time-consuming CRL checking process by an efficient revocation checking process. Third, it uses the shared secret group key to provide novel location privacy preservation through random encryption periods (REP) which ensures that the requirements to track a vehicle are always violated. Moreover, in case of revocation an OBU can calculate the new group key and update its compromised keys even if the OBU missed previous rekeying process. For each of the aforementioned accomplishments, we conduct security analysis and performance evaluation to demonstrate the reliable security and efficiency of the proposed schemes

Security and Privacy Issues in Wireless Mesh Networks: A Survey

This book chapter identifies various security threats in wireless mesh network (WMN). Keeping in mind the critical requirement of security and user privacy in WMNs, this chapter provides a comprehensive overview of various possible attacks on different layers of the communication protocol stack for WMNs and their corresponding defense mechanisms. First, it identifies the security vulnerabilities in the physical, link, network, transport, application layers. Furthermore, various possible attacks on the key management protocols, user authentication and access control protocols, and user privacy preservation protocols are presented. After enumerating various possible attacks, the chapter provides a detailed discussion on various existing security mechanisms and protocols to defend against and wherever possible prevent the possible attacks. Comparative analyses are also presented on the security schemes with regards to the cryptographic schemes used, key management strategies deployed, use of any trusted third party, computation and communication overhead involved etc. The chapter then presents a brief discussion on various trust management approaches for WMNs since trust and reputation-based schemes are increasingly becoming popular for enforcing security in wireless networks. A number of open problems in security and privacy issues for WMNs are subsequently discussed before the chapter is finally concluded.Comment: 62 pages, 12 figures, 6 tables. This chapter is an extension of the author's previous submission in arXiv submission: arXiv:1102.1226. There are some text overlaps with the previous submissio

A Survey on Wireless Sensor Network Security

Wireless sensor networks (WSNs) have recently attracted a lot of interest in the research community due their wide range of applications. Due to distributed nature of these networks and their deployment in remote areas, these networks are vulnerable to numerous security threats that can adversely affect their proper functioning. This problem is more critical if the network is deployed for some mission-critical applications such as in a tactical battlefield. Random failure of nodes is also very likely in real-life deployment scenarios. Due to resource constraints in the sensor nodes, traditional security mechanisms with large overhead of computation and communication are infeasible in WSNs. Security in sensor networks is, therefore, a particularly challenging task. This paper discusses the current state of the art in security mechanisms for WSNs. Various types of attacks are discussed and their countermeasures presented. A brief discussion on the future direction of research in WSN security is also included.Comment: 24 pages, 4 figures, 2 table

Longitude : a privacy-preserving location sharing protocol for mobile applications

Location sharing services are becoming increasingly popular. Although many location sharing services allow users to set up privacy policies to control who can access their location, the use made by service providers remains a source of concern. Ideally, location sharing providers and middleware should not be able to access users’ location data without their consent. In this paper, we propose a new location sharing protocol called Longitude that eases privacy concerns by making it possible to share a user’s location data blindly and allowing the user to control who can access her location, when and to what degree of precision. The underlying cryptographic algorithms are designed for GPS-enabled mobile phones. We describe and evaluate our implementation for the Nexus One Android mobile phone

State of The Art and Hot Aspects in Cloud Data Storage Security

Along with the evolution of cloud computing and cloud storage towards matu- rity, researchers have analyzed an increasing range of cloud computing security aspects, data security being an important topic in this area. In this paper, we examine the state of the art in cloud storage security through an overview of selected peer reviewed publications. We address the question of defining cloud storage security and its different aspects, as well as enumerate the main vec- tors of attack on cloud storage. The reviewed papers present techniques for key management and controlled disclosure of encrypted data in cloud storage, while novel ideas regarding secure operations on encrypted data and methods for pro- tection of data in fully virtualized environments provide a glimpse of the toolbox available for securing cloud storage. Finally, new challenges such as emergent government regulation call for solutions to problems that did not receive enough attention in earlier stages of cloud computing, such as for example geographical location of data. The methods presented in the papers selected for this review represent only a small fraction of the wide research effort within cloud storage security. Nevertheless, they serve as an indication of the diversity of problems that are being addressed