Aggregation of Trustworthy Announcement Messages in Vehicular Ad Hoc Networks

Vehicular ad hoc networks (VANETs) allow vehicle-to-vehicle communication and, in particular, vehicle-generated announcements. Vehicles can use such announcements to warn nearby vehicles about road conditions (traffic jams, accidents). Thus, they can greatly increase the safety of driving. However, their trustworthiness must be guaranteed. A new system for vehicle-generated announcements is presented that is secure against external and internal attackers attempting to send fake messages. Internal attacks are thwarted by using an endorsement mechanism based on multisignatures. Besides, this scheme ensures that vehicles volunteering to generate and/or endorse trustworthy announcements do not have to sacrifice their privacy.