CORBA, OpenDoc, Fresco and OpenStep Beginner's Page
This page is intended to be a starting point for learning about CORBA, OpenDoc, Fresco and OpenStep...technologies that probably need to be integrated in order to produce large-scale, truly interoperable, component based, multimedia applications.
To participate in the integration and free implementation of these technologies, please join the FSLU (Free Software Lovers Union) at http://www.ied.com/~honza/fslu/
CORBA - Common Object Resource Broker Architecture
CORBA is a generic system for implementing communication between "objects".
The "objects" in a CORBA system can be separate objects in the same application, completely separate programs, database objects, or pretty much anything else. They can be written in a variety of common programming languages, and adapting existing programs to a CORBA interface for IPC is not excessively difficult.
OpenDoc
OpenDoc can best be described as a set of defined interfaces (implementable on top of CORBA, or conceivably in other object systems) that provide functionality for multimedia applications built from independent vendor components. It supports embedding components inside other applications, much like Microsoft's proprietary OLE.
OpenStep
OpenStep is the specification for the API of the NeXT system. It is an operating-system independent API for programs written in the Objective-C language. It provides GUI, postscript display, event ("notification") handling, distributed objects, and advanced programming functionality.
Fresco
Fresco is an existing free system which achieves many of the same goals of OpenDoc and OLE...embedding of multiple graphical parts in a single application "page". In general, it provides a lower-level programmer's interface than OpenDoc, and a few powerful features not seen in OpenDoc.
Be sure to also see my many links to CORBA, OpenDoc, etc resources for a very extensive list.
CORBA Free Implementations
From Bill Janssen at Xerox:
I believe that our ILU system would provide a solid base for communicating applications, and will eventually also provide interoperability with all existing RPC and distributed object systems. It currently supports CORBA, ONC RPC, and HTTP. See ftp://ftp.parc.xerox.com/pub/ilu/ilu.html for more information.
Electra
is a free CORBA V2 Object Request Broker (ORB) supporting the
implementation of reliable distributed applications. An application is
said to be reliable if its behavior is predictable in spite of partial
failures, network partitions, and in spite ob objects joining and
leaving the system dynamically. Optionally, Electra objects can be
replicated to achieve fault tolerance.
DOME -
commercial ORB. Free binary available for Linux -
http://www.oot.co.uk
CHORUS/COOL ORB -
commercial ORB. Evaluation binaries for download. -
http://www.chorus.com
OpenDoc Free Implementations
Arguably, the CILabs source (the "definitive" implementation used by Apple and IBM") is free to some degree. The FSLU is looking into exactly what strings are attached. Currently (and probably indefinitely) the IBM and Apple development libraries are also free.
OpenStep Free Implementations
The GNUStep project has ported most of the OpenStep functionality.
See http://www.gnustep.org
If you find this useful or just have questions, please contact the author Braddock Gaskill, or visit his web pages.
First written on 29 August 1996
CVS Version: $Id: corbainfo.html,v 1.7 1996/11/16 14:37:35 braddock Exp $