A utility model for timely state update in distributed wargame simulations

ABSTRACT

In distributed wargame simulations, the states of simulation entities need to be updated and sent to other simulation nodes in a timely manner, which may incur high overhead on the network. Thus, how to efficiently use the limited bandwidth of the network is very important to the performance of distributed wargame simulations. In this paper, a utility model is proposed to evaluate the relative importance of a simulation entity. In our proposed utility model, the utility of an entity is determined by the number of entities on which this entity may have influence and the distances between this entity and the entities within its area of influence. Based on the utility model, we may devise some flexible updating mechanisms which can utilize the bandwidth more efficiently. For example, the state updates of an important entity which may have nodes with a high frequency; on the other hand, the state updates of an entity with little importance may be sent to other simulation nodes with a low frequency. In this paper, we will focus on the utility computation of a simulation entity rather than the flexible state updating mechaisms for the simulation entities. Our proposed utility computation mechanism is general and can be easily implemented using the HLA services. Experimental results show that the utility computation mechanism incurs little overhead.

References

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