Performance experiments with the high level architecture and the total airport and airspace model (TAAM)

HLA is a mechanism for interconnecting disparate simulations over a network. Its main application has been distributed wargaming, where simulations prepared by different organizations are combined in a virtual environment for a specific training exercise or study objective. The individual simulations are called federates in the HLA world, while the collection of federates, that interoperate in the virtual world is called a federation. We investigate an alternate use of the HLA. It is possible to imagine that the federates are not disparate simulations, but a single simulation that has been partitioned along some logical axis and federated with itself. Such a self-federation has many attractive features. First, the data structures are identical among the various federates. Secondly, there are no problems with common definitions of data elements, messages, interactions, or algorithms, as the federates all derive from the same source code. Finally, the mechanism can be viewed as a lightweight parallel simulation engine, as all of the details of synchronization, time management, message passing, and monitoring have already been well thought out and implemented in the HLA system. The Total Airport and Airspace Model (TAAM) is a large air traffic simulation that is a worldwide standard for aviation analysis. Traditionally it has been used for regional studies, consisting of a small subset of airports and airspace. Recently, there has been interest in using TAAM for much larger scenarios, such as simulations of traffic throughout the entire United States. It is possible, but not practical, to run such simulations with TAAM.