Trajectory as an Identity: Privacy-Preserving and Sybil-Resistant Authentication for Internet of Vehicles

With the advancement of the 5G network, the Internet of Vehicles (IoV) is becoming more and more attractive for academic researchers and industrial. A main challenge of IoV is to guarantee the authenticity of messages and protect drivers’ privacy simultaneously. The majority of privacy-preserving authentication schemes for IoV adopt pseudonyms or group signatures to achieve a balance between security and privacy. However, defending the Sybil attacks in these schemes is challenging. In this work, we propose a novel privacy-preserving authentication scheme for announcement messages, which utilizes the trajectories of vehicles as their identities. When an authenticated message is verified, the verifier is convinced that the message is generated by a vehicle that has a unique masked trajectory. Meanwhile, the real trajectories of vehicles are kept private. In particular, our scheme achieves Sybil attack resistance without the limitation of trajectory length even when the attacker is allowed to use cloud services.

An Improved Group Signature Scheme with VLR over Lattices

For group signatures (GS) supporting membership revocation, verifier-local revocation (VLR) mechanism is the most flexible choice. As a post-quantum secure cryptographic counterpart of classical schemes, the first dynamic GS-VLR scheme over lattices was put forward by Langlois et al. at PKC 2014; furthermore, a corrected version was shown at TCS 2018. However, both designs are within Bonsai trees and featuring bit-sizes of group public-key and member secret signing key proportional to log N where N is the group size; therefore, both schemes are not suitable for a large group. In this paper, we provide an improved dynamic GS-VLR over lattices, which is efficient by eliminating a O log N factor for both sizes. To realize the goal, we adopt a more efficient and compact identity-encoding technique. At the heart of our new construction is a new Stern-type statistical zero-knowledge argument of knowledge protocol which may be of some independent cryptographic interest.

A Survey on Proxy Re-Signature Schemes for Translating One Type of Signature to Another

Proxy Re-Signature (PRS) complements well-established digital signature service. Blaze-Bleumer-Strauss discussed PRS in 1998 for translating a signature on a message from Alice into a signature from Bob on the same message at semi-trusted proxy which does not learn any signing-key and cannot produce new valid signature on new message for Alice or Bob. PRS has been largely ignored since then but it has spurred considerable research interest recently for sharing web-certificates, forming weak-group signatures, and authenticating network path. This article provides a survey summarizing and organizing PRS-related research by developing eight-dimensional taxonomy reflecting the directional feature, re-transformation capability, re-signature key location, delegatee involvement, proxy re-signing rights, duration-based revocation rights, security model environment, and cryptographic approach. Even though multi-dimensional categorization is proposed here, we categorize the substantial published research work based on the eighth dimension. We give a clear perspective on this research from last two-decades since the first PRS-protocol was proposed.

Smart Parking with Fair Selection and Imposing Higher Privacy Constraints in Parking Owner and Driver Information

The use of private cars has enhanced the comfort of travel of individuals, but has proven to be a challenge for parking in congested downtown areas and metropolitans. This hike in the vehicle count has led to difficulty among the drivers to find a parking spot, exploiting resources and time. On the other hand, there are many idle private parking spots that remain inaccessible because of multiple reasons like unavailable owners, different open timings and so on. In order to prevent parking issues as well as to enable the use of private parking spots, smart parking applications that are easy to use by the drivers will prove to be highly effective. However, most parking lot owners and drivers face the threat of privacy which affects their willingness to participate while many others are located in a centralized location where the presence of malicious users is in plenty. In this proposed work, we have introduced a smart-parking system that is based on blockchain exhibiting qualities of privacy protection, reliability and fairness. To protect the privacy of users, vector-based encryption, bloom filters and group signatures are also insisted. This has helped us establish a more reliable smart parking system coupled with fair operation for smart contact. Experimental analysis of the real-world dataset indicates that the proposed work operates with high efficiency, establishing privacy protection, reliability and fairness.

A Privacy-Preserving Key Management Scheme with Support for Sybil Attack Detection in VANETs

Vehicular ad hoc networks (VANETs) face two important and conflicting challenges with regards to security: preserve the privacy of vehicles in order to prevent malicious entities from tracking users and detect and remove bad actors that attempt to game the system for their own advantage. In particular, detecting Sybil attacks, in which one node attempts to appear as many, seemingly conflicts with the goal of privacy preservation, and existing schemes fail on either one or both accounts. To fill this gap, we present a hierarchical key management system which uses short group signatures to preserve member privacy at lower levels while allowing mid-level nodes to detect Sybil attacks and highly trusted nodes at the top of the hierarchy to completely reveal the real identities of malicious nodes in order to prevent them from rejoining the system and for use by legal authorities. In addition, we present an argument for relaxing the requirement of backward secrecy in VANET groups in the case when no malicious activity has been detected.