CORBA - Common Object Request Broker Architecture
Published: 2023-10-30 08:37:02

CORBA, which stands for Common Object Request Broker Architecture, is a middleware technology used for building distributed and object-oriented systems. It enables different software components, written in different programming languages, to communicate and interact with one another in a distributed network. Here are some key concepts and aspects of CORBA:

1. **Objects and Components**: CORBA is based on the concept of objects and components. Software components, known as CORBA objects, can be written in various programming languages (e.g., C++, Java, Python). These objects encapsulate functionality and data.

2. **IDL (Interface Definition Language)**: CORBA uses IDL as a language-neutral interface definition mechanism. IDL allows you to define the interfaces and methods that CORBA objects expose. These IDL definitions act as a contract between different parts of the distributed system.

3. **ORB (Object Request Broker)**: The ORB is a central component in CORBA. It serves as a middleware layer responsible for managing the communication between distributed objects. The ORB handles object creation, method invocation, and data marshaling/unmarshaling.

4. **Location Transparency**: One of the key features of CORBA is location transparency. Clients can invoke methods on remote objects without needing to know their physical location. The ORB handles the low-level details of object location and communication.

5. **Language Interoperability**: CORBA promotes language interoperability, allowing objects written in different programming languages to communicate seamlessly. This is achieved through language bindings that map IDL definitions to specific programming languages.

6. **Object References**: CORBA objects are accessed through object references. These references are used by clients to invoke methods on remote objects. Object references can be passed as parameters and returned as results.

7. **Dynamic Invocation**: CORBA supports dynamic invocation, allowing clients to discover and invoke methods on objects at runtime without prior knowledge of their interfaces. This dynamic behavior is facilitated by the ORB.

8. **Security**: CORBA provides security mechanisms for authentication, authorization, and data encryption to ensure secure communication between objects.

9. **Scalability**: CORBA can be used to build scalable distributed systems. It supports features like load balancing, object activation, and dynamic object location.

10. **IDL Compiler**: To use CORBA, you typically write IDL interfaces and then use an IDL compiler to generate language-specific stubs and skeletons that facilitate communication between clients and servers.

11. **CORBA Services**: CORBA includes a set of standard services (e.g., Naming Service, Event Service, Transaction Service) that can be used to address common distributed computing challenges.

12. **History**: CORBA was developed by the Object Management Group (OMG) in the 1990s. It has gone through several versions and implementations over the years.

CORBA has been used in various domains, including telecommunications, finance, and enterprise software. However, it's important to note that while CORBA was once very popular, newer technologies like RESTful web services and gRPC have become more prevalent for building distributed systems. Nevertheless, CORBA still has a presence in legacy systems and specialized domains.