5. Verification and Validation
• The stated above, given that this is a single server
queuing system, with negative exponential
distribution for the inter-arrival time and service
time, the exact performance of the system can be
determined using queuing theory.
• As such, black-box validation is carried out by
comparing the simulation results to the results of an
alternative (queuing theory) model.
• This illustrates one test that could be performed on
the model, but obviously much more testing should
be carried out to give confidence in the model for
use in decision-making.
5.1 Queuing Theory Result
• Under the assumption of negative exponential interarrival
and service times for a single server queuing
system, the average time that a customer waits can
be computed as: