Minimization of Storage Cost in Distributed Storage Systems with Repair   Consideration
  In a distributed storage system, the storage costs of different storage nodes, in general, can be different. How to store a file in a given set of storage nodes so as to minimize the total storage cost is investigated. By analyzing the min-cut constraints of the information flow graph, the feasible region of the storage capacities of the nodes can be determined. The storage cost minimization can then be reduced to a linear programming problem, which can be readily solved. Moreover, the tradeoff between storage cost and repair-bandwidth is established. 
Quan Yu, Kenneth W. Shum, Chi Wan Sung
cs.IT cs.DC math.IT