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About OPNET

OPNET is a commercial simulation product that was developed by the MIL3 Company, Arlington, VA. It employs a Discrete Event Simulation approach that allows large numbers of closely-spaced events in a sizable network to be represented accurately and efficiently.

The representation of each level of a network in OPNET is highly structured, so the simulation process of designing, implementing, analyzing and revising the network is significantly simplified. You can design a network from the top down, using the original nodes and protocol models, or you can build from the bottom up, designing your own models and integrate with other models smoothly.

To provide useful data, network models must combine accurate descriptions of topology, data flow, and control flow. OPNET utilizes separate model formats for each. The Network Model defines the position and interconnection of communicating entities, or nodes. Each node is described by a block structured data flow diagram, or Node Model, which typically depicts the interrelation of processes, protocols, and subsystems. Each programmable block in a Node Model has its functionality defined by Process Model which combines the graphical power of a state-transition diagram with the flexibility of a standard programming language and a broad library of pre-defined modeling functions.

The behavior in each state is described by a program in the C language. Using a powerful graphical user interface (GUI) based on X Windows and multi-platform-support (DEC, HP, IBM, SUN and SGI) policy, we believe the OPNET-based models are relatively easy to port to other modeling environments.

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