On the computational security of a distributed key distribution scheme

In a distributed key distribution scheme, a set of servers help a set of users in a group to securely obtain a common key. Security means that an adversary who corrupts some servers and some users has no information about the key of a non-corrupted group. In this work we formalize the security analy...

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Detalles Bibliográficos
Autores: Daza, Vanesa, Herranz, Javier, Saez, German
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2008
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/161146
Acceso en línea:http://hdl.handle.net/10261/161146
Access Level:acceso abierto
Palabra clave:Key distribution
Secret sharing schemes
Cryptography
Provable security
Descripción
Sumario:In a distributed key distribution scheme, a set of servers help a set of users in a group to securely obtain a common key. Security means that an adversary who corrupts some servers and some users has no information about the key of a non-corrupted group. In this work we formalize the security analysis of one of such schemes [11] which was not considered in the original proposal. We prove the scheme secure in the random oracle model, assuming that the Decisional Diffie-Hellman (DDH) problem is hard to solve. We also detail a possible modification of that scheme and the one in [24] which allows to prove the security of the schemes without assuming that a specific hash function behaves as a random oracle. As usual, this improvement in the security of the schemes is at the cost of an efficiency loss. © 2008 IEEE.