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The transition to Industry 4.0 and the need for IT and OT to converge on the same physical network infrastructure has introduced new challenges in providing dependable and secure networks. The common set-up in Distributed Control Systems (DCS) to increase availability and reliability uses redundancy solutions, which can be deemed as a controller-centric approach. The IT/OT convergence is aiming towards a transition to a more network-centric approach and this thesis work is concerned with making the first steps towards these solutions. The first essential steps encompass network topology discovery and management at Layer 2.In this approach, the aim is to provide solutions for challenges that are created when replacing redundancy links, which often limit deployment, with general-purpose communication links. Due to some issues that arise with these solutions, this work is focused on investigating the possibilities of replacing the highly customized link.  Introducing the "hardware-neutral software" has a consequence of the responsibilities shifting, and having software be in charge for detection of failure and similar roles redundancy links previously provided. This work proposes a method for employing the Link Layer Discovery Protocol (LLDP) and the Simple Network Management Protocol (SNMP) for discovering the network topology between two controllers and having real-time data about the state and connectivity of switches in the network. The method was extensively investigated and evaluated for relevant industrial use cases, and a prototype was implemented and experimentally validated. The results suggest that the proposed method is a viable approach for potential use and future application.