Discrete-Event Simulation

In discrete-event simulation (DES), the operation of a system is represented as a sequence of events. Each event occurs at an instant in time and marks a change of state in the system. Simulation approaches are particularly well equipped to help users diagnose issues in complex environments.
In many organizations bottlenecks become hidden by excess inventory, overproduction, variability in processes and variability in routing or sequencing. By accurately documenting the system inside a simulation model it is possible to gain a bird’s eye view of the entire system.
Discrete Event Modeling techniques approximate continuous real-world processes with non-continuous events that you define.

Here are some examples of discrete event systems:

Screen shot 2012-11-23 at 12.51.36 PM


  • Manufacturing processes,
  • Simple and complex Service System ( bank, airport, hospitals)

A simulation model has a static structure and a dynamic structure. The static structure specifies the possible states of the model. The dynamic structure specifies how the state changes over time. When we develp a model using discrete event methodology, we define a sequence of operations being performed on entities (transactions) of certain types such as customers, documents, parts, data packets, vehicles, or phone calls. The entities are passive, but can have attributes that affect the way they are handled or may change as the entity flows through the process. Process-centric modeling is a medium-low abstraction level modeling approach.