System redundancy in power substation retrofitting applications can be deployed using either decentralized or centralized system architectures. In a decentralized architecture, network redundancy is ensured by multiple physical computers where each computer only runs a single operating system or application. In a centralized architecture, on the other hand, network redundancy is achieved by running multiple operating systems and multiple applications on the same physical server (i.e., server virtualization).
Although both decentralized and centralized architectures can be used effectively to provide retrofitted power substations with system redundancy, system integrators still need to be mindful of protecting against a number of control and management issues.