HMAC AUTHENTICATION USING DSDV IN VANET

Vehicular Adhoc Network (VANET) is a part of MANET where the nodes pass on to vehicles. HMAC authentication scheme based on secretcryptography key technique for VANETs. Even though secretkey is extensively used in VANETs to realize unidentified verification, the presented schemes based on public key suffer from long computation delay in the certificate revocation list (CRL) checking and in the key verification method, significant to high message thrashing(lose). As a result, they cannot meet the requirement of verifying hundreds of messages per second in VANETs. In this scheme, first divide the precinct into several domains, in which roadside units (RSUs) are responsible for distributing group private keys and managing vehicles in a localized manner. Then, use a hash message authentication code (HMAC) to avoid time consuming CRL checking and to ensure the integrity of messages before batch group certification. HMAC may be used to simultaneously verify both the data integrity and the authentication of a message. As a final point, adopt cooperative message authentication among entities, in which each vehicle only needs to verify a small number of messages, thus greatly alleviating the authentication burden. The security and performance analysis show that scheme is more efficient in terms of authentication speed, while keeping conditional privacy in VANETs.