Fig. 16: Detail of the different stages of the transaction level modelling, with the addition of the Neural Network and transistor (circuit) level simulation.

Modelling approaches are arranged based on how accurately (untimed, approximate, cycle-accurate) the timing of the computation and communication aspects are captured. Transaction level models then expand from B to G, with B being the specification models (which uses considers the communication and computation to be untimed) and G the implementation models (which considers both cycle-accurate timing for both computation and communication). As we approach B, the model can be regarded as a System Level Simulation, while if it approaches G, it is regarded as an architecture-level simulation. Outside this group, we find those models simulated in Python or similar tools which focus on the network topology (A) and the circuital models which materializes the implementation models (G) in the transistor or register transfer level.