Date Added: May 2011
Privacy & security are two essential security attributes of secure Vehicle-To-Vehicle (V2V) communications. To achieve the required security attributes, Public Key Infrastructure (PKI) and later Pseudonymous Public Key Infrastructure (PPKI), have been proposed. In PPKI, each vehicle is initially allotted a number of pseudonyms by the Certification Authority (CA). Each pseudonym is used to sign only a small number of messages in order to maintain privacy. The CA revokes misbehaving or malicious vehicles by publishing their pseudonyms. The CA periodically upgrades the pseudonyms of the revoked vehicles in a list known as the Certificate Revocation List (CRL). CRL in PPKI contains certificates for all the pseudonyms assigned to that revoked vehicle.