网格环境下的Web-Enabled RTI研究

在网格环境下进行基于HLA的分布仿真时,本地RTI组件(LRC)和核心RTI组件(CRC)之间必须采用SOAP协议来通信,这使得联邦大使回调的实现成为Web-Enabled RTI的关键问题。虽然XMSF和DS-Grid都实现了基于SOAP协议的联邦大使回调,但这种回调很难穿过网格环境中的防火墙。故在本地RTI组件中引入一个接收网格服务和收发守护进程,并把核心RTI组件封装为一个网格服务。这样本地RTI组件和核心RTI组件之间建立了两条基于Http协议的链接,将其中一条用于完成联邦大使回调就可解决上述问题。实验证明了这种以SOAP加HTTP协议实现的Web-Enabled RTI可以支持仿真在网格环境下运行,而且核心RTI可作为一个网格服务被用户所共享。

Research on Web-enabled RTI under Grid Condition

The realization of the federate ambassador callback becomes a key problem of Web-Enabled RTI,because the local RTI and the central RTI component must communicate with SOAP protocol when they are used by HLA-based Simulations in the grid environment. Although the federate ambassador callback based on SOAP protocol has been realized by XMSF and DS-Grid,it can hardly pass through firewalls in grid. In order to solve this problem,a receiving grid service and a dispatching demon process were added to each local RTI component,and the central RTI component was encapsulated into a grid service. So two links based on HTTP protocol were set up between the local RTI component and the central RTI component,and the callback problem could be solved by allocating one of the two links to the federate ambassador. A benchmark experiment indicates that this kind of Web-Enabled RTI based on SOAP and HTTP protocol can not only support simulation under grid condition,but also be shared as a grid service resource.