Network in the loop using HLA, distributed OPNET simulations, and 3D visualizations

Networks are playing an ever-increasing role in our world. Network size and capacity continues to increase, and consequently, become more complicated. They become so large, in fact, that the only viable test method is to use a modeling and simulation approach to analyze the effects that various inputs have on network performance, e.g., network traffic, weather effects, etc. While this may work well, it is still only an approximation to the true performance. Only a real network, with real hardware will provide real results. General Dynamics C4 Systems has been working collaboratively with the U.S. Army's CERDEC on a network in the loop architecture to combine a real network with a simulated one. This will allow a real network to be fully integrated with a simulated network such that any and all simulated nodes will pass a Turing test with respect to the real nodes. The proposed network in the loop implementation, while effective, is only proof-of-concept, handling only ICMP messages. Using OPNET Modeler 10.5, a successful implementation is demonstrated by means of passing a Turing test. This allows for multiple simulation subnets to interact with a real network. HLA 1.3 is used as a means for converting between IP traffic and simulated IP traffic. Furthermore, a 3D visualization of the entire network has been developed representing both real and simulated nodes, including effects on their communications. Future improvements may include streaming data between real and simulated nodes, full TCP and UDP traffic, and multiple routing protocol interaction