Identity-based Proxy Multi-signature Scheme Research Articles

Secure and Efficient Identity-based Proxy Multi-signature Using Cubic Residues

The term ＂proxy multi-signature＂ refers to the situation in which a proxy signer is authorized to sign a message on behalf of a group of original signers. Combined with identity-based cryptography, we proposed an efficient identity-based proxy multi-signature scheme using cubic residues without bilinear pairing. Our scheme is secure against existential forgery on adaptive chosen-message and identity attacks under the hardness of integer factorization assumption. Compared with elliptic curve or bilinear pairing, the integer factorization assumption is more reliable and easier to use because it has been developed 2500 years ago. Furthermore, our scheme is more efficient than previous schemes based on bilinear pairing.

An ID-Based Proxy Multi-Signature Scheme

Proxy multi-signature is an extension of the basic proxy signature primitive, and permits two or more entities to delegate their signing capabilities to the same other entity. Combining proxy multi-signature with identity based cryptography, in this paper, We construct a concrete identity based proxy multi-signature scheme by using bilinear pairings. Analysis shows that the scheme is capable of resisting forgery attack and can satisfy all the required security properties of a proxy signature. Furthermore, the new scheme is very simple and efficient computationally. It has the property that the size of a proxy multi-signature is independent of the number of the original signers.

On the security of an identity-based proxy multi-signature scheme

In 2000, Yi et al. proposed two proxy multi-signature schemes which enable two or more original signers to delegate their signing power to a proxy signer. Combining proxy multi-signature with identity-based cryptography, Wang et al. proposed an identity-based proxy multi-signature scheme in 2007. Their scheme is claimed to be secure in the random oracle model. However, in this study, the author shows that Wang et al.'s scheme is vulnerable to a forgery attack described in this study.

Improvement of identity-based proxy multi-signature scheme

A proxy signature scheme allows a proxy signer to sign messages on behalf of an original signer, a company or an organization. A proxy multi-signature scheme is an extension of the basic proxy signature scheme, and permits two or more original signers to delegate their signing powers to the same proxy signer. Recently, Wang and Cao proposed an identity-based proxy multi-signature scheme. This scheme is very simple and efficient since it is an extension of the identity-based aggregate signature scheme due to Gentry and Ramzan. Though the identity-based aggregate signature scheme of Gentry and Ramzan is secure in the random oracle model, in this paper, we find that the identity-based proxy multi-signature scheme of Wang and Cao is not secure unless each proxy secret key can only be used to generate at most one proxy signature. Finally, we propose an improvement to overcome this weakness, which is more simple and efficient than the identity-based proxy multi-signature scheme of Wang and Cao. We show that the improvement is existentially unforgettable in the random oracle model under the computational Diffie–Hellman assumption.

A secure identity-based proxy multi-signature scheme

In a proxy multi-signature scheme, a designated proxy signer can generate the signature on behalf of a group of original signers. To our best knowledge, most of existing proxy multi-signature schemes are proposed in public key infrastructure setting, which may be the bottleneck due to its complexity. To deduce the complexity, several proxy multi-signature schemes are proposed in the ID-based setting. However, no formal definitions on ID-based proxy are proposed until now. To fill the gap, this paper proposes the formal definition. Furthermore, we present a proven secure ID-based proxy multi-signature scheme, which is more efficient than existing schemes in term of computational cost.

Cryptanalysis of an Identity Based Proxy Multi-Signature Scheme

In a proxy multi-signature scheme, a designated proxy signer can generate the signature on behalf of a group of original signers. Recently, Wang and Cao proposed an identity based proxy multi-signature scheme along with a security model. Although they proved that their scheme is secure under this model, we disprove their claim and show that their scheme is not secure.

Identity based proxy multi-signature

As a variation of ordinary digital signature scheme, a proxy signature scheme enables a proxy signer to sign messages on behalf of the original signer. Proxy multi-signature is an extension of the basic proxy signature primitive, and permits two or more entities to delegate their signing capabilities to the same other entity. Combining proxy multi-signature with identity based cryptography, in this paper, we define security notions for identity based proxy multi-signature schemes. We also construct a concrete identity based proxy multi-signature scheme which is provably secure in the random oracle model under the computational Diffie–Hellman assumption over pairing-friendly groups. Furthermore, the new scheme is very simple and efficient computationally. It has the property that the size of a proxy multi-signature is independent of the number of the original signers.

ID-based multi-proxy signature, proxy multi-signature and multi-proxy multi-signature schemes from bilinear pairings

In electronic world, proxy signature is a solution of delegation of signing capabilities. Proxy signatures can combine other special signatures to obtain some new types of proxy signatures. Due to the various applications of the bilinear pairings in cryptography, many identity based signature schemes have been proposed. In this paper, we propose an identity based multi-proxy signature scheme and an identity based proxy multi-signature scheme from bilinear pairings. Both of them can be regarded as a special case of corresponding variants of identity based threshold signature scheme. Based on these two schemes, we propose an identity based multi-proxy multi-signature scheme.