Research And Implementation On Grid-based Distributed Simulation System GDSS

The High Level Architecture (HLA) is a general purpose architecture for simulation reuse and interoperability. It is applied to various areas such as military, transportation, education and entertainment. However, it provides only key interfaces for collaborative operations during simulation stages, and has little considerations on dynamic management and allocations for simulation resources. Grid technology is an important information technology arising these years. It provides functions and mechanisms for large-scale resource sharing and collaboration. It shows its advantages in dynamic discovery, allocation and monitoring of resouces, which can solve the limitations of HLA simulations. Therefore, it is necessary to integrate Grid and HLA together to construct distributed simulation grid that takes advantages of both technologies to achieve scalability, fault tolerance performance and support large-scale simulation. Currently, there are lots of researches on distributed simulation grid in and out of China. However, most of them are application oriented or still at initial stages so that they are inferior in platform scalability, fault tolerance performance or dynamic deployment capabilities.This paper focuses on designing and implementing a Grid-based Distributed Simulation System (GDSS) by intergrating a Grid-based Visuallization system GVis and a highly scalable HLA-based simulation framework HIVE, both of which are developed in the State Key Lab of CAD&CG, Zhejiang University. GDSS provides realtime interaction capability for large-scale simulations, meeting requirements of dynamic scheduling and load balancing for HLA-based large-scale distributed simulation systems by providing grid services for simulation resource management.Another contribution of this paper is its design for platform scalability. GDSS is implemented in a three-layer architecture, which includes a runtime environment layer GRE, a grid portal layer GDSSPortal and a simulation framework GHIVE, which are established by extending the runtime supporting module and gird portal in GVis, HLA-based simulation framework HIVE, respectively. The three layers provide different functions and are independent of each other. GRE provides large-scale network environments for grid resource management, information management, simulation task management and data management, operating as a grid supporting environment. GDSSPortal provides users functions of accesing simulation services and interacting with them. GHIVE provides a highly scalable HLA-based simulation operation framework, an efficient communication and data filtering mechanism, and a Unified Object Model to intergrate with redering platforms. The three layers are indepent of each other and thus the architecture is scalable and cross-platform.By interactions among GRE, GHIVE, and GDSSPortal, GDSS solves critical problems for distributed simulation grid system, inclucing dynamic resource management and scheduling, dynamic task management and scheduling, automatic deployment of simulation environment. GDSS is a functional distributed simulation grid system. It is proved to be really practical and useful.