Providing secure location-aware services for cooperative vehicular Ad Hoc networks

In homeland security, the transportation system built on vehicular ad hoc networks (VANETs) is one sector among key resource sectors for national infrastructure protection plan identified by the department of homeland security (DHS) of the United States. Thus, it is an essential aspect to develop a suit of elaborately designed VANET security mechanisms for a successful homeland security infrastructure. However, all prior privacy-preserving authentication protocols for secure vehicular communications have not satisfied the fulfillment of location assurance to develop secure location-aware service applications in VANETs. In this paper, we make up for the limitations and propose an efficient privacy-preserving authentication protocol with location assurance for secure location-aware services over VANETs. In particular, we introduce the notion of location-aware credential so as to guarantee the trustworthiness of geographic location in location-aware services while providing conditional privacy preservation which is a desirable property for secure vehicular communications. Furthermore, the proposed protocol provides efficient procedures that alleviate a burden of computation for location-aware signature generation and verification on vehicles in VANETs. In order to achieve these goals, we consider online/offline signature scheme based on "hash-sign-switch" paradigm and identity-based aggregate signature scheme as our building blocks. Comprehensive simulations are conducted to confirm the efficiency and effectiveness of the proposed protocol.