What is 'Middleware'

Middleware is computer software that connects software components or applications. It is used most often to support complex, distributed applications.

In simple words, the software which helps bring the TV environment into an interactive mode is called a middleware.

In case of interactive TV, the interactivity is supplied by the manipulation of the API of the particular software installed on a set-top box. The middleware can be in the form of a native application or an application such as a "browser"

Examples of commonly-found middleware software include:

• DVB-MHP (Java) - Global standard widely deployed in Europe and Asia
• OCAP (Java) - US cable industry standard based on DVB-MHP
• BD-J (Java) - Interactivity layer for Blu-ray Disc based on DVB-MHP
• OpenTV (ANSI C) - BSkyB, UPC, Viasat, TPS
• Mediahighway (Java, MHEG-5, Pantalk) - UK terrestrial, Canal+
• Liberate (HTML/JavaScript) - NTL, Telewest
• ICTV (HTML/JavaScript) - NTL, VNL
• MHEG-5 (used in UK DTT)
• Alcatel Open Media Suite - Sasktel, BBTV, Kingston
• Microsoft TV (XHTML)
• BML - Standard used on ISDB platforms in Japan
• Espial - Escape (Browser) & Evo (Native C++ based middleware)

The current challenge faced by these companies is limited capacity of set-top-boxes* which process content through this middleware. Large amounts of testing is required to ensure that the speed and performance of the 'User Experience' is not affected. Almost all of these middleware are proprietary and subject to heavy licensing restrictions.

* - More about STB's in later posts.
References: www.wikipedia.org