On Publicly Verifiable Tokens in Group Signatures with Message-Dependent Opening
Keita Emura
Group signatures (GSs; Chaum and van Heyst, EUROCRYPT 1991) are digital signatures that allow a signer to anonymously prove group membership, while still enabling a special authority, called the opener, to identify the signer when necessary. Group Signatures with Message-Dependent Opening (GS-MDO; Sakai et al., Pairing 2012) weaken the power of the opener by introducing another authority, the admitter, who issues a message-dependent token. In previous GS-MDO schemes, these tokens can be viewed a