Secure Clustered Distributed Storage Against Eavesdroppers

摘要

This paper considers the security issue of practical distributed storagesystems (DSSs) which consist of multiple clusters of storage nodes. Noticingthat actual storage nodes constituting a DSS are distributed in multipleclusters, two novel eavesdropper models - the node-restricted model and thecluster-restricted model - are suggested which reflect the clustered nature ofDSSs. In the node-restricted model, an eavesdropper cannot access theindividual nodes, but can eavesdrop incoming/outgoing data for $L_c$compromised clusters. In the cluster-restricted model, an eavesdropper canaccess a total of $l$ individual nodes but the number of accessible clusters islimited to $L_c$. We provide an upper bound on the securely storable data foreach model, while a specific network coding scheme which achieves the upperbound is obtained for the node-restricted model, given some mild condition onthe node storage size.