The blind signature schemes are useful in some applications where the anonymity is a big issue. Examples include the online voting systems and the electronic cash systems. Since the first identity-based blind signature scheme was proposed by Zhang et al., many identity-based blind signature schemes using bilinear pairings have been proposed. But the relative computation cost of the pairing is a...

Reputation systems help users evaluate information quality and incentivize civilized behavior, often by tallying feedback from other users such as “likes” or votes and linking these scores to a user’s long-term identity. This identity linkage enables user tracking, however, and appears at odds with strong privacy or anonymity. This paper presents AnonRep, a practical anonymous reputation system...

User Controlled Identity Management Systems have the goal to hinder the linkability between the different digital identities of a user. We perform a theoretical and an experimental study of the following information leakage problem: given a consistent view on the actions of a strong identity management system (e.g. Idemix ) where k users pseudonymously issue and show some credentials, do these ...

Smart card based authentication schemes are used in various fields like e-banking, e-commerce, wireless sensor networks, medical system and so on to authenticate the both remote user and the application server during the communication via internet. Recently, Karuppiah and Saravanan proposed an authentication scheme which is based on password and one-way cryptographic hash function. They have us...

A social identity approach to the investigation of group-based reactions to a merger is outlined, in which a merger is analyzed in terms of the continuation or change of the pre-merger group identity. In two experiments, the relationship between pre-merger identification, post-merger identification, and ingroup bias was investigated using a minimal group paradigm. Results from both studies show...

In this paper, we propose to replace the national identity card, currently used in many countries, by a personal device that allows its user to prove some binary statements about himself while minimizing personal information leakage. The privacy of the user is protected through the use of anonymous credentials which allows him to prove binary statements about himself to another entity without h...

Many Chinese websites (relying parties) use OAuth 2.0 as the basis of a single sign-on service to ease password management for users. Many sites support five or more different OAuth 2.0 identity providers, giving users choice in their trust point. However, although OAuth 2.0 has been widely implemented (particularly in China), little attention has been paid to security in practice. In this pape...

User Controlled Identity Management Systems have the goal to hinder the linkability between the different digital identities of a user. We perform a theoretical and an experimental study of the following information leakage problem: given a consistent view on the actions of a strong identity management system (e.g. Idemix ) where k users pseudonymously issue and show some credentials, do these ...

Undeniable signature schemes are not publicly verifiable. Therefore, in order to prove the validity/invalidity of a message-signature pair, the signer needs to provide a proof for the rightful verifier. Since the introduction of undeniable signature schemes, various proof systems with different properties and features have been introduced to be incorporated in the structure of such schemes. Amo...

The successive overrelaxation (SOR) and the symmetric SOR (SSOR) iteration matrices are connected with the Jacobi iteration matrix in case these operators are associated with a (9, p 9)-generalized consistently ordered matrix through certain matrix identities. The validity of these identities has been proved in the last couple of years. Very recently an analogous matrix identity was shown to ho...