A New Level 3 Trust Hierarchal Certificateless Public Key Cryptography Scheme in the Random Oracle Model

Despite the fact that the traditional public key infrastructure provides Level 3 trusted authority, but its two major problems of scalability and certificate management raised the need to an alternative security infrastructure. That motivated the appearance of new technologies to replace the traditional PKI, such as the Identity based encryption, the certificateless encryption, etc. But all those new technologies are yet immature and could not introduce a trust level more than Level 2, except few trials at the level of the authority. This paper aims at introducing an integrated hierarchal certificateless scheme with a Level 3 trust authority. This is done through merging the traditional PKI hierarchy and the certificateless technology in one scheme. The new scheme employs the X509 certificate format and is free of the scalability and certificate management problems of the PKI. We also describe how our new hierarchal certificateless PKC, can be integrated with a traditional PKI through a bridge model.