CORBA (Common Object Request Broker Architecture) is a distributed object computing infrastructure that allows applications to communicate with one another regardless of programming language, operating system, or location. It uses an Interface Definition Language to specify object interfaces and an Object Request Broker to handle requests and responses between client objects and server objects. The Object Management Group developed CORBA to establish industry standards for distributed object computing.

1. Common Object Request Broker
Architecture
- PURUSHOTHAMAN N

2. WHAT IS CORBA?

3. WHAT IS CORBA?
CORBA (Common Object Request Broker Architecture) is a
distributed Object-oriented client/server platform.
It includes:
➤ An object-oriented Remote Procedure Call (RPC) mechanism
➤ Object services (such as the Naming or Trading Service)
➤ Language mappings for different programming languages
➤ Interoperability protocols
➤ Programming guidelines and patterns
CORBA uses an object-oriented model to enable collaboration
between systems on different operating systems, programming
languages, and computing hardware.

4. WHO DEVELOPED CORBA?

5. THE OBJECT MANAGEMENT GROUP (OMG)
➤ The OMG was formed in 1989 with 8 members.
➤ The OMG is the world’s largest software consortium with
more than 800 member organisations.
➤ Specifications published by the OMG are free of charge.
Vendors of CORBA technologies do not pay a royalty to the
OMG.
➤ Established to create specifications for open Distributed
computing. Its mission is to "... Establish industry guidelines
and object management Specifications to provide a common
framework for distributed Application development."

6. HISTORY OF CORBA

7. CORBA HISTORY
➤ CORBA 1.0 was introduced and adopted in December 1990.
➤ It was followed in early 1991 by CORBA 1.1, which defined the
Interface Definition Language (IDL) as well as API for applications
to communicate with an ORB.
➤ But it’s chief limitation was that it did not specify a standard
protocol through which ORBs could communicate with each other.
➤ CORBA 2.0 was adopted in December 1994. The primary
accomplishment was to define a standard protocol by which ORB
from various CORBA vendors could communicate.
➤ The IIOP ensured true interoperability among products from
numerous vendors, thus enabling CORBA applications to be more
vendor-independent.

8. CORBA
…allows applications and their objects to communicate with
each other no matter where they are and or who designed them!!

9. CORBA
…it even has its own “hello world”!!
The first thing we must do is define the interface to the
serving object in OMG IDL:
#ifndef _HELLOWORLD_IDL
#define _HELLOWORLD_IDL
module HelloWorld {
interface SimpleHelloWorld {
string sayHello();
};
};
#endif
import HelloWorld.*;
public class HelloWorldImpl
implements SimpleHelloWorldServant
{
private final java.lang.String
myString = "Hello World!";
public synchronized
java.lang.String sayHello()
throws
sunw.corba.SystemException
{
return myString;
}
}

10. COMPONENTS OF CORBA

11. ➤ CORBA uses an interface definition language (IDL) to specify
the interfaces that objects will present to the outside world.
➤ CORBA then specifies a “mapping” from IDL to a specific
implementation language such as C++ or Java.
➤ Standard mappings exist for Ada, C, C++, Lisp, Smalltalk,
Java, COBOL, PL/I and Python.
➤ There are also non-standard mappings for Perl, Visual Basic,
Ruby, Erlang, Tcl and even VHDL implemented by object
request brokers (ORBs) written for those languages.
CORBA

12. The major components that make up the CORBA architecture include
the:
➤ Interface Definition Language (IDL), which is how CORBA interfaces
are defined.
➤ Object Request Broker (ORB), which is responsible for all interactions
between remote objects and the applications that use them.
➤ The Portable Object Adaptor (POA), which is responsible for object
activation/deactivation, mapping object ids to actual object
implementations.
➤ Naming Service, a standard service in CORBA that lets remote clients
find remote objects on the networks, and
➤ Inter-ORB Protocol (IIOP).
CORBA

13. ORB
Based on client/server model of distributed computing, CORBA
inserts a “broker” between client and server
ORB is “middleware”
CLIENT
SERVER/OBJECT
IMPLEMENTATION
ORB
request
ORB
Result/
error

14. ➤ Intercepts calls
➤ Finds object
➤ Invokes method
➤ Passes parameters
➤ Returns results or error messages
ORB
…regardless of the object’s location, it’s
programming language, or even the operating
system involved.

15. ELEMENTS OF CORBA

16. ORB
➤ The Object Request Broker dispatches operation calls to the right server object.
Stub
➤ The stub is a component that connects the client object to the ORB.
Skeleton
➤ The skeleton is a server-side component that, like the client stub, connects the
server object to the ORB.
GIOP/IIOP
➤ GIOP: General Inter ORB Protocol.
➤ IIOP: Internet Inter ORB Protocol.
➤ Communication between ORBs uses a standard protocol. GIOP is a general
interoperability protocol while IIOP, a variant of GIOP, is used in TCP/IP based
networks.
CORBA ELEMENTS

17. ADVANTAGES AND DISADVANTAGES OF CORBA

18. ➤ CORBA supports many existing languages (alone/mixed).
➤ CORBA supports distribution and Object Orientation.
➤ CORBA provides out-of-the-box multi-vendor interoperability
and portability.
➤ CORBA is well-suited for request/response applications over
lower-speed networks(eg: Ethernet and Token Ring).
➤ CORBA is backed by over 700 companies : hardware,
software, cable and phone companies, banks, etc.
CORBA ADVANTAGES

19. ➤ CORBA is still growing, and not fully mature.
➤ The standard lacks many features required for putting large scale
applications. Though specific vendor implementations provide
some of these features, they are not part of the standard today.
➤ The security aspects have not been sufficiently addressed in
CORBA 2.0 These have been the major obstacles to serious and
mission-critical applications development, esp. those who still
employ legacy systems.
➤ Conventional implementations of CORBA are very good for slow
networks like ethernet, but incur considerable overhead when
used for performance sensitive applications over high speed
networks.
CORBA DISADVANTAGES

20. CONCLUSION
The main conclusion is that CORBA provides interoperability
between vendors and languages (e.g. objects developed in one
programming language like C++ may call operations on objects
developed in another language like Java).
However, there is a substantial performance cost. As a result,
current CORBA technology is not suitable for implementing
high performance group communication services.

21. SOME MAJOR PROJECTS USING CORBA
➤ Distributed Object Management Integration System(DOMIS)
➤ Information Sharing System (ISS)
➤ The ANSA project ( CORBA/WWW integration )
➤ The Web Broker
➤ The Motorola Iridium project Tools for use with CORBA
➤ METEOR multi-paradigm Workflow management system