Given by W. Furmanski, H.T. Ozdemir, G. Fox at Alliance 98 NCSA Illinois on April 27-29 98. Foils prepared 3 May 98
Outside Index
Summary of Material
Current Status of JWORB and its application to Modelling/Simulation and HPCC |
Outside Index
Summary of Material
G. C. Fox, W. Furmanski and H. T. Ozdemir |
Northeast Parallel Architectures Center, Syracuse University |
Presented at Alliance'98, NCSA, April 1998 |
JWORB is an extensibe multi-protocol network server written in Java |
Current JWORB prototype at NPAC supports HTTP (+CGI+Servlets) and IIOP protocols i.e. it can act as Web Server and CORBA Broker |
IIOP and HTTP requests are distinguished by magic headers (GIOP vs GET, POST, HEAD etc.) |
New protocols can be added via JWORB extensibility framework (one such natural extension could be RTP protocol support for streamlined media) |
JWORB runs on UNIX, Windows NT, Windows95 |
JWORB is an NPAC proposal for Object Web middleware within a 3-tier distributed object model called Pragmatic Object Web (Page 3) that integrates Java, CORBA, DCOM and WOM (i.e. XML+DOM+RDF). |
JWORB will be soon used as middleware in several Object Web applications under development at NPAC (see next pages) |
The following pages illustrate a set of JWORB testing and early prototyping activities at NPAC, starting from performance benchmarks (Pages 4, 5) |
We are replacing NPAC WebFlow middleware, initially based on JavaSoft's Java Web Servers by a mesh of JWORB servers (Page 6) |
We also intend to use JWORB as the core infrastructure technology for WebHLA - an Object Web based implementation of DMSO HLA standard for Modeling and Simulation (Pages 3,7,8,9) |
WebHLA includes communication bus given by Object Web RTI (Page 8) and CORBA Wrappers for C/C++ legacy codes (Page 9) |
Our eventual goal is WebHLA based support for Virtual Prototyping and Simulation Based Design/Acquisition systems in the High Performance FMS/IMT domains (Page 7) |
Illustration of Pragmatic Object Web concepts |
POW integrates Java, CORBA, DCOM, HPC |
JWORB itself integrates HTTP and IIOP |
Next, it links to DCOM via CORBA/COM bridge, to HPJava via RMI, to SIO via CORBA enterprise services, and to WOM via DOM |
WebHLA - an example of JWORB based 3-tier system in DoD M&S domain |
Simulation specific modules (HLA federates) plug in as CORBA objects into JWORB bus and can be accessed via Web browser front-ends |
A set of NPAC/IWT projects in the figure is involved in developing WebHLA components |
We compare here performance of several Java (and C++) ORBs; JWORB performance is satisfactory as for an early prototype |
Differences in Figs.1 and 2 are related to the use (or not) of (slow) object serialization |
C++ ORB (omniORB2 in Fig. 3) is order of magnitude faster than all Java ORBs so Java ORBs useful mainly for middleware control |
This simple demo illustrates the interplay between HTTP and IIOP protocols inside JWORB |
A Netscape4 applet connects as ORBlet to JWORB and displays real-time ping performance |
During this benchmark, client connects to JWORB also via HTTP channel by downloading a page (left frame above) - this results in transient performance loss (spike) in the IIOP channel |
WebFlow is a Web/Java based visual dataflow system with applet based visual graph editor and servlet based management of distributed computational modules |
Initial WebFlow prototype at NPAC was based on a mesh of Java Web Servers from JavaSoft (former name Jeeves) |
We are currently switching to JWORB based WebFlow middleware. |
In parallel, we are addressing WebFlow integration with Globus in the backend and with UML authoring tools in the front-end |
WebHLA is NPAC recommendation for High Performance FMS/IMT within the DoD Modernization Program |
Our roadmap shown above places WebHLA at the convergence point of CORBA, Web, M&S and HPC commodity standards |
Such Virtual Prototyping Environments for Simulation Based Acquisition are currently operated only by large industry (e.g. Boeing) |
Within WebHLA, they become affordable via integration of Defence, Enteprise, Desktop and open Web standards |
We build WebHLA in a sequence of tasks, starting from JWORB based Object Web RTI (Run-Time Infrastructure) illustrated above. |
In JWORB model, communication objects: RTIAmbassador and FederateAbmassador become Java CORBA remote objects and hence naturally accessible from Web frontends |
Since JWORB integrates CORBA and the Web, Object Web RTI enables World-Wide scalable HLA Federations. |
In our FMS PET projects within the DoD Modernization Program, we start addressing such large scale simulations involving several HPC DoD Labs (MSRCs and DCs) |
HLA/RTI provides distributed object model and software bus. |
JWORB offers smooth integration with Web and Enterprise Computing |
The actual simulation modules come from the existing C, C++, Fortan, Ada etc. legacy codes in the DoD M&S area. |
Examples of such codes we currently work with include ModSAF (above) and CMS (left). |
These codes are being now parallelized and suitably encapsulated as CORBA components or Enterprise JavaBeans within the JWORB model. |
Such wrapper technology will allow these codes to interoperate in the next generation World-Wide scalable federations |