Validating a simulation model of a large-scale operational telecommunications system.

摘要

This research meets a need for more practice of validation of simulation projects by presenting a case study of validating a simulation of a large-scale operational telecommunications system. Engineers responsible for the efficiency of an operational network commissioned an executable model of a telecommunications system to be built with the software package OPNET® Modeler, an application oriented simulation package specific to communications networks. This study documents the validation process of the simulation of that telecommunications system. The research focuses on the validation of the simulation by organizing the current techniques and methods available in the literature on simulation validation and applying those methods that are appropriate for this case study. Based on the actual validation reported in this case study, we propose a refined process that should facilitate validations of simulation projects of similar size and type.; The research highlights the importance of validation during the entire life cycle of the simulation project. It recommends several significant validation steps in the process before the development of the computer program begins. It suggests that it is important in the validation of a simulation to determine the track record of the modeling environment and the model developers' experience in order to establish the credibility of the model. It proposes that software verification should include ensuring that model developers' use standard software practices. Since the study is of an operational system, comparisons of model output with real system output are performed and model calibration is used to refine the model. Validation of this phase includes running a separate set of historical data through the simulation model after the calibration is complete.; This research produced a proposal for a refined set of methods appropriate for validating simulations of operational systems similar in type and size to the case study project. It proposes a validation process flow and outlines a set of techniques to use in the validation process. The study produced a validation of an executable model for an operational telecommunications system. That validation establishes credibility in the model so that decision makers will be confident in its results when it is used as a test bed for network engineering.