Lewis/ACTS/Boeing Experiment Demonstrates Gigabit Application Using ACTS

Layout of Lewis/ACTS/Boeing experiment.

The objective of this project was to demonstrate a satellite-based gigabit application using the Advanced Communications Technology Satellite (ACTS).

To achieve this objective, a series of numerical experiments were conducted to develop an engine inlet control system for the High Speed Research (HSR) Program. An inlet simulator was run on the NASA Lewis Research Center's Cray YMP supercomputer but wascontrolled by Boeing Corporation in Seattle, Washington. Flow visualization information was transported via ACTS to the remote site for display on a high-performance, three-dimensional graphics workstation. This enabled control system design parameters to be varied for rapid evaluation of the integrated inlet/control system performance. The experimental ACTS network allowed remote access of NASA's distributed engine simulation application to aerospace manufacturers.

Synchronous optical networks (SONET)/asynchronous transfer mode (ATM) traffic studies were performed on this unique experimental network to evaluate the network performance. The experimental SONET/ATM network's performance for this and other applications was characterized experimentally.

Accomplishments

• This was the first high-data-rate experiment to use ACTS.
• It was the first experiment to provide end-to-end ATM connectivity across the United States.
• Computational fluid dynamics simulation results were used to validate experimental data from Lewis' 10- by 10-Foot Supersonic Wind Tunnel. Computational fluid dynamics simulations and windtunnel tests at Lewis were evaluated and controlled simultaneously from the same room at Boeing Corporation in Seattle.
• Reportedly, Lewis was the first site in the United States to deploy the high-performance gigabit router ("GigaRouter") from NETSTAR.
• Lewis was the first site to use the Bus Based Gateway (BBG) developed by Cray Research, Inc. The BBG, which was designed and developed for this experiment, is now commercially available from Cray Research, Inc., as a high-performance parallel interface (HiPPI)-ATM/SONET adapter.
• Bellcore designed and developed the traffic processor for this experiment. This processor can collect ATM cell-level statistics and shape traffic on the basis of specific algorithms. A more refined version that supports OC48 speeds is being built for the NECTAR project.

Significance of the Work

• Reduced the amount of wind tunnel test time required to develop inlet control systems for high-speed engines
• Supported the High Speed Research Project inlet downselect milestone at the end of 1995
• Assessed the effect of the propagation delay on the performance of distributed computing applications
• Identified key issues in developing reliable, high-speed communication transfer protocols for aerospace applications