Robust Dynamic Coded Distributed Storage with Partially Storage Constrained Servers

Abstract

We consider the problem of Robust Dynamic Coded Distributed Storage (RDCDS) with partially storage constrained servers where the goal is to enable robust (resilient to server dropouts) and efficient (as measured by the communication costs) read and update operations, subject to the constraint that the storage at $S$ out of $N$ servers is limited by $1/K_c$ the size of the message. Building upon previously established converse arguments and achievability schemes by Jia et al., in this work we develop a set of new converse arguments and coding designs that enable us to completely characterize the fundamental limits of RDCDS with partially storage constrained servers, i.e., the minimum number of available servers for feasible update operation and the minimum communication costs for read and update operations across various server dropout scenarios.