Preserving location-privacy in vehicular networks is a challenge. On one hand, under Public Key Infrastructure (PKI) realm, changing pseudonyms has been the state-of-the-art; however, to avoid being tracked, the vehicle has to change the pseudonym when it is within a fixed or a dynamic mix zone, created using encryption or silent periods. On the other hand, under the group signature realm, super anonymity is afforded for vehicles but at the expense of slow signature verification. To benefit from the super anonymity of an optimized hybrid group signature authentication, we suggest the idea of altering authentication to form the dynamic mix crowd for an originating vehicle that needs to change its pseudonym. Our scheme has neither silent periods nor encryption; it simply utilizes the new authentication as a dynamic hiding cover for the pseudonyms changing; once the pseudonym is altered, the vehicle watches for at least one other change by any cooperative neighbor in the formed zone before it automatically demolishes the group by reverting back to the baseline authentication. Our analysis shows the easiness of forming and demolishing the dynamic groups, it proves the validity of the model by satisfying the needed vehicular security requirements, and shows acceptable performance in comparison with the baseline authentication scheme.
['Sarah Al-Shareeda', 'Füsun Özgüner']
Preserving location privacy using an anonymous authentication dynamic mixing crowd