Balanced Oil and Vinegar signature schemes and the unbalanced Oil and Vinegar signature schemes are public key signature schemes based on multivariable polynomials. In this paper, we suggest a new signature scheme, which is a generalization of the Oil-Vinegar construction to improve the efficiency of the unbalanced Oil and Vinegar signature scheme. The basic idea can be described as a construct...

Before we address the question of which properties the proposed signature schemes lack, we enumerate desirable properties of any digital signature system: 1. Authenticity: A digital signature should be authentic, in that the signature will convince the recipient that the claimed author deliberately signed the document. It should be computationally infeasible for a third party to forge the autho...

According to the American National Science and Technology Council (NSTC), the first signature recognition system was developed in 1965. Then the research continued in 1970 focusing on the potential of geometric characteristic of a signature rather than dynamic characteristic. Nowadays, signature is a commonly used identification procedure. Everyone would be required having a signature for autho...

(Sequential) Aggregate signature schemes enable a group of users u1, . . . , uk with messages m1, . . . ,mk to produce a single signature Σ which states the integrity and authenticity of all the messages m1, . . . ,mk. The length of the signature Σ is thereby significantly shorter than a concatenation of individual signatures. Therefore, aggregate signatures can improve the efficiency of numero...

An aggregate signature is a useful digital signature that supports aggregation: Given n signatures on n distinct messages from n distinct users, aggregate signature scheme is possible to aggregate all these signature into a single short signature. This single signature, along with the n original messages will convince any verifier that the n users did indeed sign the n original messages respect...

Rapid development of data processing systems has made digital signatures an essential application. A digital signature basically associates a signer with the message. Its important characteristics are easy verification, unforgeability and undeniability. However, conventional digital signature schemes generally consider only single signer situations; this is impractical, because the authorized s...

Randomizable encryption allows anyone to transform a ciphertext into a fresh ciphertext of the same message. Analogously, a randomizable signature can be transformed into a new signature on the same message. We combine randomizable encryption and signatures to a new primitive as follows: given a signature on a ciphertext, anyone, knowing neither the signing key nor the encrypted message, can ra...

In 2004, Sekhar proposed a new signature scheme with message recovery. Based on this signature scheme with message recovery, they also proposed a designated verifier signature scheme with non-repudiation of origin and a convertible designated verifier signature scheme with non-repudiation of origin. This paper, however, presents a security analysis where Sekhar’s signature schemes are vulnerabl...

A fair blind signature is a blind signature with revocable anonymity and unlinkability, i.e., an authority can link an issuing session to the resulting signature and trace a signature to the user who requested it. In this paper we first revisit the security model for fair blind signatures given by Hufschmitt and Traoré in 2007. We then give the first practical fair blind signature scheme with a...

We introduce a new concept called convertible undeniable signature schemes. In these schemes, release of a single bit string by the signer turns all of his signatures, which were originally undeniable signatures, into ordinary digital signatures. We prove that the existence of such schemes is implied by the existence of digital signature schemes. Then, looking at the problem more practically, w...