## 4 Results: State-of-the-Art Approaches
### Simulation of Cybersecurity and Interoperability in IoUT
Our plans include this extension, in order to be able to represent packet flows during communications, as well as their protocols and the integration of the SLAM (simultaneous localization and mapping) ontology [120]. In addition, a plethora of co-simulation tools exist across various domains. Open Simulation Platform (OSP, [[https://opensimulationplatform.com/](https://opensimulationplatform.com/)]([https://opensimulationplatform.com/](https://opensimulationplatform.com/)), accessed on 20 November 2022) is an open-source initiative for co-simulation of the maritime industry. The motivation of this project is the constant growth of complexity of systems and software of ships, and other maritime/offshore assets, resulting in several difficulties in their designing. Another co-simulation method, which utilizes a bunch of tools, is presented in related work of [PERSON] et al. [121]. By combining cyber-physical components, as well as cybersecurity scenarios, it evaluates the impact of security threats of a communication network. In this procedure, a combination of network and power system simulation tools is established. In another related work [115], a co-simulation framework, called GridAttackSim is proposed, to simulate various cyber threats and their consequences in a smart grid infrastructure. The simulation output can be visualized and compared to recognize malicious behaviors and strategies of adversaries. The framework uses three different simulation tools. Finally, the upcoming trend of our era cannot be omitted. Above IoT lies a new technology, the digital twin [122], which emerged to replace most of the simulation tools that delimited solely in the prediction functionality. New generation platforms can manage any type of virtual and physical entities interoperating in the Internet of Everything (IoE), replicate any kind of processes, predict how they will perform, and act based on these predictions towards optimizing performance and available resources. This new kind of simulation platform (sense, analyze, act) is introduced in the era of the digital twin. \begin{table}
\begin{tabular}{c c c c c} \hline
**Tool** & **Attack Variety** & **Realism** & **Advantages** & **Disadvantages** \\ \hline GridAttack Sim [115] & Medium & Medium & Co-simulation with NS-3, detailed report analysis, simple GUI & Designed mainly for surface smart grid topologies \\  & & & Powerful visualization, detailed analysis report and probabilistic feature which recommends implementation of security mechanisms & Two licenses, commercial one has limited features \\  & & & Design of complex network topologies, real-time packet capture, connection of the simulated world to the real world & Two licenses, commercial one has limited features \\ HackIt [109; 110] & High & High & Variety of protocols integration Autonomous adversary emulation and incident response, choice of defender or attacker & Difficult configuration \\ NeSSi2 [113; 114] & Medium & Medium & Manual creation of network with variety of devices Visualization of adversary moves, analysis from well-known databases (MITRE ATT\&CK, Zero Trust, etc.) & Anticipated variety of attacks \\ BloodHound [119] & High & Medium & Integrated function for queries & Developed mainly for Active Directory (AD) and Azure environment \\ \hline \end{tabular}
\end{table} 
Table 5: Comparison of security simulation tools.