An OPNET-based 3-tier network simulation architecture

Simulation is an indispensable technique to evaluate the performance of computer networks, and along with the continuous growth of network scale and diversity, the simulation systems become more enormous and complex. In this paper, we present an approach to create a distributed and Web-based 3-tier simulation architecture based on the external model access (EMA) library of OPNET. With this architecture, we can partition modeling and simulation tasks efficiently, and synchronously access the system functions regardless of the location. And at the same time we can share the extremely expensive simulation resources, including the OPNET platform and the hardware devices, among a potentially large number of users. The extensible markup language (XML) is also adopted to describe network simulation scenarios that can be automatically translated into simulation scripts. This technology is especially predominant when focusing on large-scale network simulations.