2024/03/15 by Rémi A. Chou, Chou, Remi A., Jörg Kliewer +1 · 3 citations
Computer Science · #Advanced Data Storage Technologies #Caching and Content Delivery #Cloud Data Security Solutions #Cryptography and Security (cs.CR) #FOS: Computer and information sciences #Information Theory (cs.IT)
paper · pdf · doi:10.48550/arxiv.2403.10676
openalex publication_date 2024/03/15 · openalex created_date 2024/03/20 · openalex updated_date 2026/07/28
Consider the problem of storing data in a distributed manner over T servers. Specifically, the data needs to (i) be recoverable from any τ servers, and (ii) remain private from any z colluding servers, where privacy is quantified in terms of mutual information between the data and all the information available at any z colluding servers. For this model, our main results are (i) the fundamental trade-off between storage size and the level of desired privacy, and (ii) the optimal amount of local randomness necessary at the encoder. As a byproduct, our results provide an optimal lower bound on the individual share size of ramp secret sharing schemes under a more general leakage symmetry condition than the ones previously considered in the literature.