Aggregate Level Simulation Protocol - Basic Tenets

Basic Tenets

DARPA sponsored the design of a general interface between large, existing, aggregate-level combat simulations. Aggregate-level combat simulations use Lanchestrian models of combat rather than individual physical weapon models and are typically used for high-level training. Despite representational differences, several principles of SIMNET applied to aggregate-level simulations:

• Dynamic configurability. Simulations may join and depart an exercise without restriction.
• Geographic distribution. Simulations can reside in different geographic locations yet exercise over the same logical terrain.
• Autonomous entities. Each simulation controls its own resources, fires its own weapons and, when one of its objects is hit, conducts damage assessment locally.
• Communication by message passing. A simulation uses a message-passing protocol distribute information to all other simulations.

The ALSP challenge had requirements beyond those of SIMNET:

• Simulation time management. Typically, simulation time is independent of wall-clock time. For the results of a distributed simulation to be "correct," time must be consistent across all simulations.
• Data management. The schemes for internal state representation differ among existing simulations, necessitating a common representational system and concomitant mapping and control mechanisms.
• Architecture independence. Architectural characteristics (implementation language, user interface, and time flow mechanism) of existing simulations differed. The architecture implied by ALSP must be unobtrusive to existing architectures.