An aggregate signature scheme is a digital signature that supports aggregation: Given n
signatures on n distinct messages from n distinct users, it is possible to aggregate all these …

A credential system is a system in which users can obtain credentials from organizations
and demonstrate possession of these credentials. Such a system is anonymous when …

A new public-key encryption scheme, along with several variants, is proposed and analyzed.
The scheme and its variants are quite practical and are proved secure against adaptive …

Byzantine agreement requires a set of parties in a distributed system to agree on a value
even if some parties are corrupted. A new protocol for Byzantine agreement in a completely …

Secure and reliable group communication is an active area of research. Its popularity is
fueled by the growing importance of group-oriented and collaborative applications. The …

This paper presents efficient off-line anonymous e-cash schemes where a user can
withdraw a wallet containing 2 ℓ coins each of which she can spend unlinkably. Our first …

This paper addresses the problem of designing practical protocols for proving properties
about encrypted data. To this end, it presents a variant of the new public key encryption of …

We present the first aggregate signature, the first multisignature, and the first verifiably
encrypted signature provably secure without random oracles. Our constructions derive from …

We present a new protocol that allows two players to exchange digital signatures over the
Internet in a fair way, so that either each player gets the other's signature, or neither player …

Many cryptographic tasks and protocols, such as non-repudiation, contract-signing, voting,
auction, identity-based encryption, and certain forms of secure multi-party computation …