In this paper, first presented at SIW 2023, Karl Söderbäck, Oscar Bergman, and Björn Löfstrand present a solution for achieving persistent task state in federated simulations through a standardized approach. Focus is put on the ETR (Entity Tasking and Reporting) module of the NATO FOM (Federation Object Model) where the authors propose extensions to represent the state of tasks in the federation.
By representing the task state in the federation, it can be stored and restored as part of the federation state from a central component, removing the need for each federate to handle the task state internally. This simplifies the restoration process and removes the responsibility of task persistence from individual federates.
Additionally, a pattern for (re-)initializing federates is suggested. The pattern uses HLA services for Object and Ownership Management, to utilize the federation state when restoring after a federate loss.
In conclusion, the proposed extensions to the NATO FOM and pattern for (re-)initializing federates provide a standardized approach for persistent task state in federated simulations, which can be easily adapted by future federates. Future work will focus on developing the extensions further to be integrated into future official versions of the FOM to represent the task state in the common standard.
If you’re interested in learning more about our approach and the NATO FOM extensions we proposed, we invite you to download the full paper on the link below.