Efficient Certificateless Signature Scheme without Bilinear Pairings

This paper has compared two certificateless signature scheme without bilinear pairings, which pointed out that the He's scheme had higher efficiency, simpler algorithm and shorter signature length, but it had lower security. Compared with the He's scheme, the Chen's scheme had higher security, but it had higher calculation cost, lower efficiency and longer signature length, which was not practical in wireless network environment that requiring low bandwidth. In order to overcome the disadvantages of the two schemes, we propose a new improved certificateless signature scheme, which had simple calculation, high efficiency and short signature length. We prove the scheme to be secure based on the discrete logarithm problem.