ABSTRACT
Digital Twin (DT) technology and the creation of intelligent virtual replicas of physical systems have gained much attention from industry and academia in recent years. Its adoption in different scenarios, but mainly in the industry 4.0 area, has driven its development, particularly in Cyber Physical Systems (CPS), Industrial Internet of Things (IIoT), and smart manufacturing. DT is defined extensively in the literature as a system that continuously integrates data from the physical world into a virtualized logical environment that allows different types of analysis to be performed in this environment. Possible changes in the physical world are previously validated in the virtual world, automatically generating actions to be performed in the real environment. Although device virtualization, device simulation, and emulation techniques are well known in the context of networking, the adoption of DT principles in the fields of computer networks and distributed systems is still at an early stage of development and standardization. The contributions of this chapter revolve around the definition, characterization, and status of DTs in computer networks. We present the software technologies enablers of the Network Digital Twin (NDT) concept and discuss ongoing approaches to deploy the DT digital counterpart along with their adoption challenges. In addition, we categorize recent NDT works based on their definitions and main properties.
