Middleware Explained

Middleware is an increasingly used buzzword -but what exactly does it mean? There have been many interpretations of the term ‘middleware’ since it was first coined around a decade ago. In the past, popular interpretations have usually been concerned with remote database access software and transactional systems. More recently, the term has most often been applied to distributed systems platforms such as DCE and CORBA although it has also been applied to systems as diverse as workflow support environments and the Web! Perhaps the best we can do by way of a general definition is to say that middleware refers to any software layer that is placed above the distributed systems infrastructure (e.g. the operating system APIs offered by workstations and PCs connected via the Internet) and below the application. One thing we can state clearly about middleware: it is something which OS network designers think is part of the application, and something which application designers think is part of the OS or network. The essential role of middleware is to abstract over the complexity and heterogeneity of distributed infrastructures and thereby provide a simpler, cleaner and value-added programming environment for the developers of distributed applications.