Anzeige
Erschienen in:
2007 | OriginalPaper | Buchkapitel
Knowledge-Binding Commitments with Applications in Time-Stamping
verfasst von : Ahto Buldas, Sven Laur
Erschienen in: Public Key Cryptography – PKC 2007
Verlag: Springer Berlin Heidelberg
Aktivieren Sie unsere intelligente Suche, um passende Fachinhalte oder Patente zu finden.
Wählen Sie Textabschnitte aus um mit Künstlicher Intelligenz passenden Patente zu finden. powered by
Markieren Sie Textabschnitte, um KI-gestützt weitere passende Inhalte zu finden. powered by
We prove in a non-black-box way that every bounded list and set commitment scheme is
knowledge-binding
. This is a new and rather strong security condition, which makes the security definitions for time-stamping much more natural compared to the previous definitions, which assume
unpredictability
of adversaries. As a direct consequence, list and set commitment schemes with partial opening property are sufficient for secure time-stamping if the number of elements has an explicit upper bound
N
. On the other hand, white-box reductions are in a sense strictly weaker than black-box reductions. Therefore, we also extend and generalize the previously known reductions. The corresponding new reductions are
$\Theta(\sqrt{N})$
times more efficient, which is important for global-scale time-stamping schemes where
N
is very large.