An efficient certificateless ring signature scheme

To overcome the drawbacks such as high computational cost, unreasonable security model and long signature length in existing certificateless ring signature schemes, we propose an efficient certificateless ring signature scheme in this paper. Our construction is inspired by some efficient ID-based ring signature schemes, and uses bilinear pairings as a basic tool. Using a reasonable security model, the unforgeability of the proposed scheme is proven based on the intractability of the computational Diffie-Hellman (CDH) problem. The signature length of the new scheme is only |G ₂|+n|G ₁| (|G _i | is the bit length of an element in group G _i , i =1, 2). Compared with other existing certificateless ring signature schemes, the newly proposed scheme has a shorter signature length and is more efficient and practical. Foundation item: Supported by the National Natural Science Foundation of China (60673070) and the Natural Science Foundation of Jiangsu Province (BK2006217)