The Research On DDM Algorithm In HLA

As the combination of simulation technology and computer network technology, Distributed Interactive Simulation (DIS) has experienced several periods: SIMNET, DIS, ALSP, and a new technology framework, called HLA, has been recently proposed in order to solve the interoperability and reusability among various kinds of simulation applications. HLA has become a standard of IEEE in 2000.With the increase of the size and complexity of DIS systems, how to effectively reduce the data quantity transmitted in the network and to save the width of the network in order to improve the system's scalability has become a very important issue in recent years. Data Distribution Management (DDM) is one of the most important functions in HLA/RTI. According to the supply-demand relationship of simulation entities, DDM can perform data transmission among the simulation platforms, and in the meantime realize data filtering to satisfy the scalability of the simulation system.The contents of the thesis are listed below.(1) An introduction to the content, architecture and function of HLA and RTI.(2) The implementation of DDM is described and some limitations of classical algorithms for DDM are analyzed.(3) A dynamic DDM algorithm based on weight function is proposed. For improving DDM, by increasing the precision of region matching the data quantity and consumption of multicast address in the network are reduced in our method.(4) The efficiency of each DDM algorithm is greatly depended on the characteristics of problems. In order to provide a suitable algorithm for different simulation missions, an algorithm selection strategy based on coverage and extent is proposed.