An efficient certificateless signature scheme without bilinear pairings

During these years, the research field of certificateless signature (CLS) scheme is promptly investigated as the key escrow problem in identity-based cryptography can be solved via CLS concept. However, due to the bandwidth limitation of mobile communication and the resource-constraint property of handheld mobile devices, most CLS schemes cannot fulfill the requirement of computation efficiency for mobile communication architecture. Hence, the design of lightweight CLS protocol refined from traditional cryptosystem technologies for existing mobile communication environment becomes one of the most important research trends. In this paper, we demonstrate a novel CLS scheme which is immune against bilinear pairings. Without the heavy computation of bilinear pairings, our proposed scheme is efficient and practical for mobile communication. Meanwhile, the proposed CLS scheme possesses strong security density owing to the adoption of point addition of elliptic curve cryptography. A formal security analysis is presented to guarantee the security robustness of our CLS protocol under the hardness of breaking elliptic curve discrete logarithm problem.