HF radio network simulation based on automatic link establishment (ALE) and distributed routing policies

The application of the automatic link establishment (ALE) procedures of MIL-STD-188-141A, combined with improved signal processing technology found in advanced modems, provides the basic elements to create adaptive high frequency (HF) radio networks. Dynamic changes in ionospheric conditions and noise fluctuations make the HF network a hostile one, where links between nodes are subject to frequent failure. The addition of adaptive routing and information management enhances network robustness in this environment. This suggests the use of a distributed routing algorithm in which convergence to the shortest path is of primary concern. However, routing decisions derived from such distributed processes exhibit an inherent uncertainty due to the randomness of link failures and the latency of network performance information. The authors describe predictions of a computer simulation of a wide area HF radio network that invokes ALE procedures, adaptive routing, and information management protocols. Aspects include the impact of modem interleaver delay time, encryption synchronization delay, management overhead, and message handling on throughput and network latency. Recommendations are presented with respect to the application of statistical neural processing to improve network management in this environment