“…This system redundancy policy just gives the bottom line of the redundancy ratio for achieving the target requirement. The system redundancy ratio and the system positioning policy that we considered in this paper will be utilized in computing the quantity of the control system that has limited capacity to support several services in network design (Choi et al, 2009). Network designers or planners should have a holistic view on long-term network planning strategy including economic efficiency, service level agreement, network operation and maintenance, and so on.…”