### Industry 4.0 IIoT, Cloud, and Edge Computing for Next-Generation Offshore Wind Farms
At the vPAC node, virtual intelligent electronic device (vIED) docker-based containers, designed using relay technology, are configured and deployed in the docker engine. The Kalkitech's virtual protection relay (VPR) reference system affirms that using vIEDs in a dockerized environment meets and exceeds the vIED to vIED performance and time requirements [11]. Additionally, the environment facilitates redundancy, resiliency through container migration, and ease of deployment [61]. These vIEDs subscribe to the SVs and process the data. The vIEDs send the processed SVs to the disturbance recorder (a containerized or VM instance) to determine the power quality by detecting transients or short-duration voltage variations in the electrical network under observation. Additionally, these vIEDs exchange IEC 61850 Generic Object-Oriented Substation Events (GOOSE) messages -- according to the GOOSE protocol, as described at [[https://www.typhoon-hil.com/documentation/typhoon-hil-software-manual/References/iec_61850_goose_protocol.html](https://www.typhoon-hil.com/documentation/typhoon-hil-software-manual/References/iec_61850_goose_protocol.html)]([https://www.typhoon-hil.com/documentation/typhoon-hil-software-manual/References/iec_61850_goose_protocol.html](https://www.typhoon-hil.com/documentation/typhoon-hil-software-manual/References/iec_61850_goose_protocol.html)) (accessed on 4 June 2024) -- with each other through a virtual switch and with external process-levelequipment such as circuit breakers through the process bus network [62]. Lastly, these vIEDs communicate with other station-level equipment by sending IEC 61850 Manufacturing Message Specification (MMS) signals to the historian database in the enterprise network or other energy management systems in the cloud control center. Software-Defined Networking (SDN) and Network Function Virtualization (NFV) for Next-Generation Offshore Wind Farms  
Central to the next-generation offshore wind farm's IIoT-Edge data-acquisition system (shown in Figure 3) is a communication network that leverages SDN and NFV technologies to facilitate critical, latency-sensitive data transfer [63; 64]. There is a need to model robust communication frameworks to guarantee seamless offshore wind farm operations [65]. Conventionally, wind farm developers source their networking equipment from one or more vendors to support various network functions [66]. These communication networks, referred to as traditional networks in this paper, run distributed architectures to support industrial OT network operations. While these traditional networks have dominated the current designs of large-scale communication networks in offshore wind farms and other industrial OT networks, they face several technical and logistical challenges. These traditional network architectures incur huge cost implications and are quite complex to manage when more devices, users, and network traffic volumes increase [67]. Further, configuring and managing these networks involves individual-component manual configurations of individual devices, increasing the risk of configuration errors as the network enlarges [68]. These networks face vendor lock-in for cases where the wind farm developer relies heavily on proprietary hardware and software from a single vendor. Additionally, this vendor lock-in limits innovation such that network administrators cannot customize the network functionalities to suit their business intents outside the provisions of the vendor [69; 70]. Given the siloed network management approach, there is limited global network visibility and control; hence, it is challenging to troubleshoot issues or optimize network resources [71]. Most importantly, these networks have a longer convergence time, referring to the time the network takes to recover and resume normal operations after a fault such as a link or a device failure [67]. Table 2 shows a feature-based comparison between the traditional communication networks and the software-defined networks.