We present a non-interactive chosen ciphertext secure threshold encryption system. The proof of security is set in the standard model and does not use random oracles. Our construction uses the recent identity based encryption system of Boneh and Boyen and the chosen ciphertext secure construction of Canetti, Halevi, and Katz.

Over the past two decades in Australia, the field of gifted education has expanded considerably. The term ‘giftedness’ has effectively entered mainstream discourse. The field of gifted education, which nowadays operates as a compensatory function of mass education, is comprised of groups of people who broadly share in the concept of giftedness but contest, through discourse, its meanings and pr...

Geometric modelers typically define surfaces as images of closed polygonal regions under polynomial or rational maps, called patches. The images, also called patches, do not overlap but join along curves in lR . Differential topologists define surfaces as domains of invertible maps, also called patches, from lR to open sets in lR . The patches cover the surface by overlapping in open subsets. T...

Early research on online self-presentation mostly focused on identity constructions in anonymous online environments. Such studies found that individuals tended to engage in role-play games and anti-normative behaviors in the online world. More recent studies have examined identity performance in less anonymous online settings such as Internet dating sites and reported different findings. The p...

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What people are, to themselves and others, is a product of a lifetime of interpersonal interactions superimposed over a very general ethological endowment (Harré, & van Langenhove, 1999). According to Eckert (2000) an individual is a linguistic agent building social meaning in their mutually-engaged community. Individual identity is constructed with group identities, and engagement in the world...

The concept of signcryption, introduced to the public by Zheng [19], is a primitive that combines the functions of both digital signature and public key encryption. The efficiency of signcryption is higher than sequential composition of digital signature and public key encryption. Identity-based signcryption is a specific type of signcryption, in which each user’s public key can be a string ide...

To minimize the damage caused by key-exposure in ID-based signatures, in ISPEC’06 Zhou et al (2006) proposed an ID-based key-insulated signature (IBKIS) scheme. However, their scheme is not strong key-insulated, i.e, if a user’s helper is compromised, the adversary can derive all of this user’s secret keys for any time period. Moreover, in practice, to alleviate the damage in case of key-exposu...

In ACM CCS 2008, Boldyreva et al. proposed an elegant way of achieving an Identity-based Encryption (IBE) with efficient revocation, which we call revocable IBE (RIBE). One of the significant benefit of their construction is scalability, where the overhead of the trusted authority is logarithmically increased in the number of users, whereas that in the Boneh-Franklin naive revocation way is lin...