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Secret sharing schemes for (k, n)consecutive access structures
(Springer, 20180901)
Article
Restricted access  publisher's policyWe consider access structures over a set P of n participants, defined by a parameter k with 1 = k = n in the following way: a subset is authorized if it contains participants i, i + 1,...,i + k  1, for some i ¿ {1,...,nk+1}. ... 
On the information ratio of nonperfect secret sharing schemes
(20171201)
Article
Open AccessA secret sharing scheme is nonperfect if some subsets of players that cannot recover the secret value have partial information about it. The information ratio of a secret sharing scheme is the ratio between the maximum ... 
An algebraic framework for DiffieHellman assumptions
(201701)
Article
Open AccessWe put forward a new algebraic framework to generalize and analyze Di eHellman like Decisional Assumptions which allows us to argue about security and applications by considering only algebraic properties. Our D`;kMDDH ... 
Equivalences and blackbox separations of Matrix DiffieHellman problems
(201702)
Article
Open AccessIn this paper we provide new algebraic tools to study the relationship between different Matrix DiffieHellman (MDDH) Problems, which are recently introduced as a natural generalization of the socalled Linear Problem. ... 
Attributebased encryption implies identitybased encryption
(20171101)
Article
Open AccessIn this study, the author formally proves that designing attributebased encryption schemes cannot be easier than designing identitybased encryption schemes. In more detail, they show how an attributebased encryption ... 
On the optimization of bipartite secret sharing schemes
(20120501)
Article
Open AccessOptimizing the ratio between the maximum length of the shares and the length of the secret value in secret sharing schemes for general access structures is an extremely difficult and longstanding open problem. In this ... 
Ideal hierarchical secret sharing schemes
(20120124)
Article
Open AccessHierarchical secret sharing is among the most natural generalizations of threshold secret sharing, and it has attracted a lot of attention since the invention of secret sharing until nowadays. Several constructions of ideal ... 
Finding lower bounds on the complexity of secret sharing schemes by linear programming
(20130501)
Article
Open AccessOptimizing the maximum, or average, length of the shares in relation to the length of the secret for every given access structure is a difficult and longstanding open problem in cryptology. Most of the known lower bounds ... 
Signcryption schemes with threshold unsigncryption, and applications
(201403)
Article
Open AccessThe goal of a signcryption scheme is to achieve the same functionalities as encryption and signature together, but in a more efficient way than encrypting and signing separately. To increase security and reliability in ... 
On the efficiency of revocation in RSAbased anonymous systems
(20160801)
Article
Open AccessThe problem of revocation in anonymous authentication systems is subtle and has motivated a lot of work. One of the preferable solutions consists in maintaining either a whitelist LW of nonrevoked users or a blacklist ... 
Efficient cryptosystems from 2kth power residue symbols
(201704)
Article
Open AccessGoldwasser and Micali (J Comput Syst Sci 28(2):270–299, 1984) highlighted the importance of randomizing the plaintext for publickey encryption and introduced the notion of semantic security. They also realized a cryptosystem ... 
The Kernel Matrix DiffieHellman Assumption
(201612)
Article
Open AccessWe put forward a new family of computational assumptions, the Kernel Matrix DiffieHellman Assumption. Given some matrix A sampled from some distribution D, the kernel assumption says that it is hard to find “in the exponent” ...