Now showing items 1-8 of 8

  • Extending Brickell-Davenport theorem to non-perfect secret sharing schemes 

    Farràs Ventura, Oriol; Padró Laimon, Carles (2015-02)
    Article
    Open Access
    One important result in secret sharing is the Brickell-Davenport Theorem: every ideal perfect secret sharing scheme de nes a matroid that is uniquely determined by the access structure. Even though a few attempts have been ...
  • Ideal hierarchical secret sharing schemes 

    Farràs Ventura, Oriol; Padró Laimon, Carles (Springer, 2010)
    Conference report
    Open Access
    Hierarchical secret sharing is among the most natural generalizations of threshold secret sharing, and it has attracted a lot of attention from the invention of secret sharing until nowadays. Several constructions of ideal ...
  • Ideal hierarchical secret sharing schemes 

    Farràs Ventura, Oriol; Padró Laimon, Carles (2012-01-24)
    Article
    Open Access
    Hierarchical 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 ...
  • Multipartite secret sharing schemes 

    Farràs Ventura, Oriol (Universitat Politècnica de Catalunya, 2010-07-27)
    Doctoral thesis
    Open Access
    This thesis is dedicated to the study of secret sharing schemes, which are cryptographic methods to share information in a secure way. The topics that are considered in the thesis are two of the main open problems in secret ...
  • Natural generalizations of threshold secret sharing 

    Farràs Ventura, Oriol; Padró Laimon, Carles; Xing, Chaoping; Yang, An (2014-01-14)
    Article
    Open Access
    We present new families of access structures that, similarly to the multilevel and compartmented access structures introduced in previous works, are natural generalizations of threshold secret sharing. Namely, they admit ...
  • On the information ratio of non-perfect secret sharing schemes 

    Farràs Ventura, Oriol; Hansen, Torben; Kaced, Tarik; Padró Laimon, Carles (2017-12-01)
    Article
    Open Access
    A secret sharing scheme is non-perfect 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 ...
  • On the optimization of bipartite secret sharing schemes 

    Farràs Ventura, Oriol; Metcalf-Burton, Jessica Ruth; Padró Laimon, Carles; Vázquez González, Leonor (2012-05-01)
    Article
    Open Access
    Optimizing 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 long-standing open problem. In this ...
  • Optimal non-perfect uniform secret sharing schemes 

    Farràs Ventura, Oriol; Hansen, Torben; Kaced, Tarik; Padró Laimon, Carles (Springer, 2014)
    Conference report
    Open Access
    A secret sharing scheme is non-perfect if some subsets of participants 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 ...