IPTV/VoD: The open fourth platform

Opening up a television platform is a profound step that can't be considered lightly – other than the technological steps, there are commercial barriers that make it a difficult process. It is television based on a new idea rather than a new infrastructure. The experience of IPTV is a radical change from what we have all known before, as it provides true personalisation and two-way interactivity. Viewing comes through interacting rather than passively sifting through a funnel of unordered material we didn’t opt in for.

The nature of on-demand content empowers the viewer and enables true freedom of choice that very few have had before, and the good news is that after the initial learning curve, it's extraordinarily compelling and easy to sell.

The infrastructure of most platforms in the UK is almost always proprietary and a closely-guarded trade secret. Each broadcaster uses their own systems that are fully customised, with suppliers falling over themselves to lock their clients into their technologies and controls. All share an implementation of the common MPEG-2 standard (for both compression and RF transport), but implement their scheduling, play-out, EPG, conditional access and middleware differently.

IPTV technologies generally tend to follow open standards that enable easy interoperability, unless of course you use products provided by Microsoft, Siemens, Alcatel or any other gorilla. The fundamental architecture of an IPTV platform is based on web standards that have been tweaked – mark-up languages like HTML, XML and others. Menus are web pages that are specially adapted for TV viewing.

To develop for Sky, you need to spend extortionate amounts of money buying into Open TV's proprietary middleware and/or their own WapTV microbrowser (which uses the ETSI-certified WTVML language derived from WML). NTL and Telewest use the Two Way TV "Arc" system twinned with the HTML-based TV Navigator software originally built by the now-dissolved Liberate Technologies (now SeaChange). Freeview/OnDigital comes closest with the open MHEG-5 standard, which is an absurd declarative language created for digital Teletext services that runs through a Pantalk virtual machine. Don’t even ask about Homechoice or KIT.

All of these wildly different interactivity engines are implemented differently and have helped a market for cross-platform publishing spring up in the iTV world.

IPTV as technological platform owes much to its formative precedent of streaming video over the web. Typical standards (again unless you use proprietary products like Microsoft Windows Media or On2) revolve around MPEG-4 (all 22 parts), SMIL, real-time streaming protocols like RTP/RTSP, signalling protocols like SAP/SDP, transactional messaging through XML-based web services (SOAP, WSDL, UDDI etc) and distribution systems like multicasting.

Today's IP set-top boxes are more compliant with the latest W3C standards (XHTML 2, CSS 3.0) than web browsers like IE, Firefox, Opera and/or Safari. Asynchronous communications like Web 2.0's AJAX (Asynchronous Javascript and XML done through the XMLHttpRequest object) has been a staple of the iTV environment for years.

Each piece of CPE has a different integration path because of differing hardware, but the most crucial point that underpins all this effort towards interoperation and compatibility is that the IPTV community has learnt from the lessons taught to us by the web and has opted to work within an open framework that tries its best to provide standardised abstraction when it comes to integrating proprietary systems.

Using open technology standards is commercially beneficial as it allows innovators to easily cross-train an already enormous pool of developer talent that is available on the market today. Graphic designers need a re-think course to learn about TV display, and developers need to learn TV-specific extensions of middleware and differences between PC and set-top box capabilities.

The barriers to building IPTV services are 1000 per cent lower than they are for TV platforms we have today. Almost anyone can set up a demonstration service literally within hours for negligible cost. Adapting existing web applications is incredibly easy as they use the same technologies.