Core-Edge design of storage area networks—A Single-edge formulation with problem-specific cuts

Optimization and heuristic methods for the design of medium to large storage area networks (SANs) are in the early stages of development, but are required if large clustered storage systems are to become a viable alternative to expensive monolithic storage. We present here a new mixed-integer formulation for optimal design of a storage area network. Our formulation models the Single-edge Core-Edge topology. Using a testbed of medium to large problems, we compare the solution times for our new formulation to the current benchmark in the literature—our formulation solves in significantly less time with an off-the-shelf optimization software package. We also generate problem-specific cuts to further reduce the solution time for our formulation. An algorithm, which includes an integer programming subproblem, is described for generating some of these cuts. For all test problems, the cuts yield a further reduction in the solution time.