Efficient Certificateless Online/Offline Signature with Tight Security
Since public key cryptography is usually build using computationally expensive operation, it has been out of reach for resource constrained and low power devices. Today there are a large number of low power devices in use and they perform complex tasks. In this paper, the authors show a view of the how Certificateless schemes are constructed. Then, they present a Certificate-Less Online/Offline Signature (CLOOS) Scheme and give a tight security reduction to the Gap Diffie-Hellman problem in the random oracle model. Even though other schemes exist that are constructed using less number computational steps, if they take into account the size of keys their scheme will be more efficient. Thus, their scheme is light weight and has a low communication overhead.