1. A method of network topology determination for at least one Control & Instrumentation (C&I) system in an industrial facility (IF), comprising: discovering a network type, and all nodes and interconnecting networking devices including switches in said C&I system; collecting additional connectivity information including a connection of said nodes to a specific port; determining network relationships of said nodes and said interconnecting networking devices in said C&I system, and generating a network topology diagram of said C&I system from said nodes and said interconnecting networking devices, said additional connectivity information, and said network relationships, wherein said discovering, said collecting, said determining, and said generating are all automatically implemented.