H. A. Bahr and R. F. DeMara, 
"Data Bandwidth Reduction for Embedded Simulation using Concurrent Behavior 
Models," submitted to Simulation on December 31, 2004.

Abstract:
Maintaining coherence between the independent views of multiple participants at 
distributed locations is essential in an Embedded Simulation environment. 
Currently, the Distributed Interactive Simulation (DIS) protocol maintains 
coherence by broadcasting the entity state streams from each simulation station. 
In this dissertation, a novel alternative to DIS that replaces the transmitting 
sources with local sources is developed, validated, and assessed by analytical 
and experimental means.
The proposed Concurrent Model approach reduces the communication burden to 
transmission of only synchronization and model-update messages. Necessary and 
sufficient conditions for the correctness of Concurrent Models in a discrete 
event simulation environment are established by developing Behavioral Congruence 
¦·B(EL, ER) and Temporal Congruence ¦·T(t, ER) functions. They indicate model 
discrepancies with respect to the simulation time t, and the local and remote 
entity state streams EL and ER, respectively. Performance benefits were 
quantified in terms of the bandwidth reduction ratio BR=N/I obtained from the 
comparison of the OneSAF Testbed Semi-Automated Forces (OTBSAF) simulator under 
DIS requiring a total of N bits and a testbed modified for the Concurrent Model 
approach which required I bits. In the experiments conducted, a range of 100 ?¨¹ 
BR ?¨¹ 294 was obtained representing two orders of magnitude reduction in 
simulation traffic.