We construct the first several efficient threshold ring signatures (TRS) without random oracles. Specializing to a threshold of one, they are the first several efficient ring signatures without random oracles after the only earlier instantiation of Chow, Liu, Wei, and Yuen [22]. Further specializing to a ring of just one user, they are the short (ordinary) signatures without random oracles summ...

Known practical blind signature schemes whose security against adaptive and parallel attacks can be proven in the random oracle model either need five data exchanges between the signer and the user or are limited to issue only logarithmically many signatures in terms of a security parameter. This paper presents an efficient blind signature scheme that allows a polynomial number of signatures to...

Consumer approval of the online auction paradigm is demonstrated by rapidly expanding transaction volumes. Bidders can access a wider variety products, and sellers reach larger audience through platforms. However, privacy concerns have reduced users’ trust in platforms, complicated disputes led consumers to lose faith auctions, negatively impacting market growth. The emergence blockchain techno...

The increasing demand for secure and anonymous transactions raises the popularity of ring signatures, which is a digital signature scheme that allows identifying group possible signers without revealing identity actual signer. This paper presents efficient supersingular isogeny-based linkable schemes will find potential applications in post-quantum technologies. We develop by applying Fiat-Sham...

In this paper, we suggest solutions to the key exposure problem in ring signature. In particular, we propose the first forward secure ring signature scheme and the first key-insulated ring signature schemes. Both constructions allow a (t, n)-threshold setting. That is, even t secret keys are compromised, the validity of all forward secure ring signatures generated in the past is still preserved...

In threshold ring signature schemes, any group of t entities spontaneously conscript arbitrarily n − t entities to generate a publicly verifiable t-out-of-n signature on behalf of the whole group, yet the actual signers remain anonymous. The spontaneity of these schemes is desirable for ad-hoc groups such as mobile ad-hoc networks. In this paper, we present an identity based (ID-based) threshol...

In this paper, we propose a forward secure ring signature scheme without random oracles. With forward security, if a secret key of a corresponding ring member is exposed, all previously signed signatures containing this member remain valid. Yet the one who has stolen the secret key cannot produce any valid signature belonged to the past time period. This is especially useful in the case of ring...

Proxy signatures are very useful tools when one needs to delegate his/her signing capability to other party. After Mambo et al.’s first scheme was announced, many proxy signature schemes and various types of proxy signature schemes have been proposed. Due to the various applications of the bilinear pairings in cryptography, there are many IDbased signature schemes have been proposed. In this pa...