Dynamic Pivot for Layer Partition-based Matching Algorithm of DDM based on Regions Distribution

High Level Architecture (HLA) is architecture for reuse and interoperation of simulations. In HLA paradigm, the Runtime Infrastructure (RTI) provides a set of services. Data Distribution Management (DDM) service reduces message traffic over the network. DDM aims to control and limit the data exchanged between federates during federation. Each federate may inform the RTI about its intention to publish some data or it may subscribe to receive a subset of the published data. DDM services are used to reduce the transmission and receiving of irrelevant data and aimed at reducing the communication over the network. These services rely on the computation of the intersection between “update” and “subscription” regions. When calculating the intersection between update regions and subscription regions, the higher computation overhead can occur. Currently, there are several main DDM filtering algorithms. This paper proposes a dynamic pivot choosing to use in the layer partition-based matching algorithm for DDM in the HLA-based large-scale distributed simulations. The new algorithm chooses the dynamic pivot based on regions distribution in the routing space. The binary partition-based algorithm is fundamentally based on a divide and conquers approach. This algorithm always chooses the midpoint as the pivot point of routing space. This approach promises low computational overhead, since it does not require unnecessary comparisons within regions in different partitions. The proposed algorithm firstly calculates the regions distribution. Then, the partitioning among regions performs based on the result of choosing pivot based on region detection and defines the matching area that entirely covers all regions which need to match with regions at pivot point. The proposed algorithm provides the more definite matching area between update region and subscription region during matching process. This algorithm guarantees low computational overheads for matching process and reduce the irrelevant message among federates