The enforcement of reusability and shareability of products or components based on new technology standards for simulation and modeling is of paramount importance. In this thesis we first utilize DMSO HLA as the basic fundamental to design a customization environment for Web-based modeling and simulation. The environment is able to offer the interoperability framework between a broad spectrum of simulation paradigms, including both real-time and logical time models and to support a huge number of participants. To fulfill the goal we proposed three main tasks to be done. First, we proposed the mechanism to reduce the communication overhead and to balance the information consistency among large participants by incorporating a three-level control mechanism and Dynamic Filtering Strategy (DFS) within HLA RTI. In the second task, we proposed a load balancing algorithm to efficiently utilize the resource over the network environment. At the last task we use Java 3D to build a virtual reality application on the environment.