An efficient and provably-secure certificateless signature scheme without bilinear pairings

SUMMARY Certificateless public key cryptography simplifies the complex certificate management in the traditional public key cryptography and resolves the key escrow problem in identitybased cryptography. The certificateless signature scheme is studied widely as an important primitive. Following the pioneering work done by Al‐Riyami et al., many certificateless signature schemes using bilinear pairings have been proposed ever since. However, the relative computation cost of the pairing is approximately 20 times higher than that of the scalar multiplication over the elliptic curve group. To improve the performance we propose a certificateless signature scheme without bilinear pairings. With the running time being reduced greatly, our scheme is more practical than the previous related schemes for practical application. Copyright © 2011 John Wiley & Sons, Ltd. The key findings presented in the paper is described as follows. (1) We proposed an efficient certificateless signature scheme without pairings. (2) We also show the proposed scheme is secure in the random oracle. (3) The experimental results show the proposed scheme has better performance than the related schemes.