Object Management Group
The Object Management Group was founded in 1989 as a non-profitable corporation of eleven companies. Today the group has hundreds of members and the board of directors boasts prominent companies such as Sun Microsystems, Oracle Corporation, Borland Corporation, Hewlett-Packard Co. and Hitachi, Ltd. “The OMG Object Model is based on a small number of basic concepts: objects, operations, types, and sub-typing. An object can model any kind of entity, for example a person, a ship, a document, a department, a tuple, a file, a window manager, or a lexical scanner. A basic characteristic of an object is its distinct identity” (Soley, R. M. , 1992).
One of the OMG’s specifications is CORBA (Common Object Request Broker Architecture). CORBA is the “OMG’s open, vendor-independent architecture and infrastructure that computer applications use to work together over networks” (OMG, 2003). “Using the standard protocol IIOP, a CORBA-based program, will work on almost any computer, programming language, operating system and network, can interoperate with a CORBA-based program from the same or another vendor, on almost any other computer, operating system, programming language, and network” (OMG, 2003).
Real time system users, such as Telecoms, European Air traffic control and finance are major subscribers of CORBA, as it copes well with servers that handle a large number of clients, at high hit rates, with high reliability. CORBA is found in the computer rooms of many of the world’s largest websites. Thousands of sites rely on CORBA, including: UBS AG, Raytheon Company, Thames Water, American Airlines, Federal Express, Nike, and UK Data Collection Service.
CORBA can also be used by smaller companies, running specialized versions of it in real-time systems, and small-embedded systems. CORBA however has dwindled in popularity over the last few years. Companies have embraced the Internet, with Java and Enterprise JavaBeans (EJB) becoming the dominant enterprise middleware choice, as well as XML (Extensible Markup Language) which is now used extensively, for Internet messaging. Microsoft’s DCOM (Distributed Component Object Model) and dotNet is also favoured by smaller companies and as such has become a competing middleware contender.
The main reason for this is that CORBA cannot solve all the distributed middleware problems and companies have had to make further arrangements in an ever expanding and complex integrating workplace. In September 2001 the OMG responded to this with a new approach called MDA (Model Driven Architecture), which is based on UML (Unified Modelling Language(tm)). UML is a third-generation method for specifying, visualizing, and documenting the artefacts of an object-oriented system under development. UML represents the unification of the Booch, Objectory, and OMT methods, and additionally incorporates ideas from a number of other methodologists.
Companies can generate platform-specific UML models, from which the same companies can automatically generate code for any specific type of middleware the company requires. The OMG is effectively asking companies and the ‘open source’ groups to describe their applications in a neutral, declarative language (UML) and then to generate any APIs (Application Programming Interface) needed from UML diagrams. To make this happen, the OMG has committed itself to developing standards and profiles to support the conversion of UML to code.