5 research outputs found
A Survey and Refinement of Repairable Threshold Schemes
We consider repairable threshold schemes (RTSs), which are threshold schemes that enable a player to securely reconstruct a lost share with help from their peers. We summarise and, where possible, refine existing RTSs and introduce a new parameter for analysis, called the repair metric. We then explore using secure regenerating codes as RTSs and find them to be immediately applicable. We compare all RTS constructions considered and conclude by presenting the best candidate solutions for when either communication complexity or information rate is prioritised
Localised multisecret sharing
localised multisecret sharing scheme is a multisecret sharing scheme for an ordered set
of players in which players in the smallest sets who are authorised to access secrets are close
together in the underlying ordering. We define threshold versions of localised multisecret
sharing schemes, we provide lower bounds on the share size of perfect localised multisecret
sharing schemes in an information theoretic setting, and we give explicit constructions of
schemes to show that these bounds are tight. We then analyse a range of approaches to
relaxing the model that provide trade-offs between the share size and the level of security
guarantees provided by the scheme, in order to permit the construction of schemes with
smaller shares. We show how these techniques can be used in the context of an application
to key distribution for RFID-based supply-chain management motivated by the proposal of
Juels, Pappu and Parno from USENIX 2008