(k, n)-Consecutive access structures

We consider access structures over a set of n participants, defined by a parameter k with 1 <= k <= n in the following way: a subset is authorized if it contains at least k consecutive participants. Depending on whether we consider the participants placed in a line (that is, participant 1 is n...

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Detalles Bibliográficos
Autores: Herranz Sotoca, Javier|||0000-0001-5141-7234, Sáez Moreno, Germán|||0000-0002-7463-7173
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/431444
Acceso en línea:https://hdl.handle.net/2117/431444
https://dx.doi.org/10.1007/s10623-025-01651-7
Access Level:acceso abierto
Palabra clave:Information theory
Coding theory
Secret sharing schemes
Distributed cryptography
General access structures
Information ratio
Codificació, Teoria de la
Informació, Teoria de la
Classificació AMS::94 Information And Communication, Circuits::94A Communication, information
Àrees temàtiques de la UPC::Informàtica::Informàtica teòrica
Descripción
Sumario:We consider access structures over a set of n participants, defined by a parameter k with 1 <= k <= n in the following way: a subset is authorized if it contains at least k consecutive participants. Depending on whether we consider the participants placed in a line (that is, participant 1 is not next to participant n) or in a circle, we obtain two different families, that we call (k, n)-line-consecutive and (k, n)-circle-consecutive access structures, respectively. Such access structures can appear in real-life situations involving distributed cryptography, which makes it more interesting to look for the best secret sharing schemes that can realize them. For both families, we characterize which are the configurations (k, n) that admit ideal secret sharing schemes. For the non-ideal (k, n)-consecutive access structures, we give both upper and lower bounds on the information ratio of the best secret sharing schemes that can realize them. Some of these bounds are obtained after proving relations between the information ratios of access structures in the two considered families.