Research Of Data Management In HLA Distributed Simulation

Nowadays Distributed Interactive Simulation (DIS) is one of the focuses in the simulation field, and HLA is the main direction of DIS development in the future. High Level Architecture (HLA) is the main idea of developing the common mainframe of modeling and simulation, which was the first goal of Department of Defense (DoD) of USA's M&S Master Plan. It is designed to facilitate the interoperability of simulation application and reusability of simulation resource. Based on a series of modeling standards and developing rules, more flexible management mechanism of time, communication mechanism of the network and management mechanism of distributing data were provided. DIS based on HLA links simulation entities distributed widely. It is very important to transfer data between entities. So data management is the core content of the HLA simulation. HLA provides data distributed management, but it can't solve the condition in which there is too much data and many entities distributed widely. It is important to choose the effective method for data management and reduce the distributed information in the network. The article researches the data management in the HLA simulation, using the National Economic Mobilization Simulation and Practice as the background. First it introduces the purpose and significance of the National Economic Mobilization Simulation and Practice, and it bring forward the main problems of distributed data management. Then it introduces the HLA standard, the Run-Time Infrastructure and the course of developing HLA applications. After analyzing the capability demand of data management in the distributed simulation, the article introduces the three typical data management structure. According the condition of National Economic Mobilization, it builds the structure in which data is saved at home and is all managed by center server. Then it expatiates how to keep the coherence of the distributed data. The article analyses the theory of HLA data distributed management, and how to implement it in pRTI. It also brings forward the limitation of HLA data distributed when the data is too superfluous. The article transports data through entities by XML. It uses XML as the assistance of HLA. Then it researches how to use HLA data distributed management and XML technique together. At last, the article researches the data flow in entities, the management of pRTI interface and data interface. Then it analyses how to collect and save the simulation data, how to realize the time management in entities.