210 likes | 323 Vues
A Web-based Distributed Simulation System. Christopher Taewan Ryu Computer Science Department California State University, Fullerton. Overview. Project background HLA A web-based distributed simulation Implementation approach Future work. Project Background.
E N D
A Web-based Distributed Simulation System Christopher Taewan Ryu Computer Science Department California State University, Fullerton
Overview Project background HLA A web-based distributed simulation Implementation approach Future work
Project Background • Telecommunication Forecaster Predictor (TFP) • Performs analysis on communications between DSN sites and spacecrafts • Web-TFP (Web version of TFP) • No program installation or upgrade • No data updating and reconfiguration • No license • TFP anywhere and anytime with a browser
Architecture of Web-TFP Linux or Solaris Server Client Apache Matlab Web Browser PHP/ JAVA Matlab CGI or DWR Matlab Server TFP
5 • Input • Parameters, data files, and program files • Operation • Select a mission Interface Run Receive output
Computer Simulation • Importance of Computer Simulation • For significant cost saving, better control and understanding of given objects and phenomenon • Defense, medical, entertainment, etc. • Important in building many mission-critical systems such as space mission and defense applications--high cost and reliability. • Challenges • Developing a realistic complex simulation system requires tremendous amount of time and effort • Many simulation systems in different organizations (e.g., DoD, NASA have developed various simulation systems in the past). • Interoperability among different systems • Reusability
High Level Architecture (HLA) • First developed by the DoD • To support interoperability and reuse • HLA has been standardized for distributed computer simulations under IEEE Standard 1516. • Any system that conform to the standard can work with any HLA implementation based on the same standard • Several open-source implementations of HLA such as Open HLA (OHLA) and Portico are available (in Java, C++). • Portico fully conform to IEEE Standard 1516.
HLA Framework … • RTI is the fundamental component of HLA • Provides a set of software services that are necessary to support federates to coordinate their operations and data exchange during a runtime execution. • Simulations don’t communicate with each other directly. All communications among simulations are managed by RTI • providing high scalability, interoperability, and reusability of components.
GUI (Java Web Start) HLA Simulation Monitor (Java 3D) Web Service Proxy Federate RTI Simulation Controller Federate Architecture • Proxy federate is to support Web service (implementation of SOA) • Web service and HLA provides different levels of interoperability • Scalability and performance
Environment Setup • Portico for RTI • Can run on Windows, Linux, or Mac platforms. • Apache Tomcat • Apache Axis • Java 3D • Target simulations, Internet, Browser
Interfaces Simulation objects are be added using the console
Advantages and Disadvantages of Web Services in HLA • Advantages • Substantially larger set of development environment and languages (that can be supported by HLA) • Easier to deploy HLA federates in WAN environment using HTTP protocol (stateless) • Larger scale of interoperability • Can you web browser as interface (all advantages of web browser)—particularly important to our project • Disadvantages • Lower performance than C++ or Java API • May require additional knowledge on Web service and HTTP
Future Work Migrate the Web-TFP or other related systems to the HLA-based platform Provide 3D interfaces for users for better interaction