Villiappan talks MHEG and broadcast/IP debate
Press release from Well Above
Giri Valliappan, Director of Market Development, IMPALA (International MHEG Promotion Alliance) recently discussed the ‘MHEG Interaction Channel – broadcast and IP combined.’ Here follow his view and conclusions:
One of the great debates occupying the broadcast world at the moment – a debate that is set to intensify – is how broadcast network services are going to combine with those delivered via IP networks. The potential for such hybrid broadcast broadband scenarios via a single receiver device is clear for all to see. The popularity of over- the-top (OTT) video services like Hulu in the USA and the BBC’s iPlayer in the UK clearly indicate a high level of consumer demand for quality TV content that can be downloaded or streamed on-demand by the user.
The major challenge in hybrid networks is to allow broadcasters and content providers to be able to maintain control both of their content and brand in such an environment, while providing viewers with the flexibility of seamless access to content that they are interested in watching.
This requirement forms the basis of recent work to enhance the MHEG-5 public standard interactive TV with the development of the MHEG-5 Interaction Channel (MHEG-IC).
MHEG-5 – as used by Freeview and Freesat in the UK, FreeView NZ, TVB in Hong Kong and recently specified by Freeview Malaysia and South Africa’s DTT platform – is a low-cost, high performance solution for interactive TV services including hybrid broadcast broadband operation. MHEG-5 facilitates the development of successful ‘horizontal’ or retail receiver markets using country-specific profiles and effective conformance test suites to ensure interoperability between different receiver implementations. 2010 will see the deployment of MHEG-5 within some new digital media platforms across the Asia Pacific region. This will initially support the rollout of a platform EPG that will provide listings information on all channels regardless of the channel being watched. The platform EPG will also allow channel and the services’ branding onscreen as well as integrated PVR support including series links and accurate recording control.
MHEG-5 Interaction Channel (MHEG-IC)
Recent work by the DTG in the UK has lead to the development of the MHEG-5 Interaction Channel (MHEG-IC), which enables an extension of broadcast interactive services to be delivered via an IP connection.
In order to address the finite capacity of the broadcast network to carry interactive content, set-top boxes, integrated digital TVs (iDTVs) and PVRs conforming to the MHEG-5 IC specification can be connected to a broadband connection through the home network and public internet using a standard ISP connection. Interactive applications, streamed AV content and associated data can be accessed either via the broadcast carousel transmission or via the IP connection.
The principles behind the MHEG-IC are to provide a seamless viewer experience of broadcast delivered content augmented with content delivered over IP as an extension of the channel or network. Broadcasters have full editorial control of the user experience. The MHEG-IC gives access to streamed on-demand video content in addition to traditional text and graphics as well as the ability to support secure transactions.
Whilst there is strong consumer demand for on-demand services such as catch-up TV, the widespread deployment of the MHEG-IC will be dependent upon the availability of fast, good quality of service and uncapped broadband connections. Most consumer devices are not professionally installed and the ease of connection to the home network is paramount in the success of any broadband content. For this reason, the MHEG-IC uses the same standard protocols used to deliver web content to PCs: TCP-IP, HTTP and HTTPS. This means that no special configuration of the home network is needed – if it’s possible to browse the web from your home PC, then the MHEG-IC will also work when connected to the same network.
The MHEG-IC can access content (applications, text, graphics and streaming media) from either the broadcast network or the IP connection. The MHEG-IC uses a sophisticated ‘Hybrid File System’, where the user in not aware whether the content is delivered via broadcast or over IP. This enables broadcasters to create common applications that can work on both IP-connected and unconnected receivers in a seamless and user-friendly way. The MHEG-IC allows the application to determine whether or not an IP connection is possible (i.e. the receiver is equipped with the appropriate hardware and software) and whether or not it is actually available (i.e. has the user actually connected the receiver to the home network?).
MHEG-IC and streaming media
MHEG-5 can access and control video and audio streams; these can be delivered either via the usual broadcast methods or with the MHEG-IC extension, via the IP connection. Streamed video at up to at least 2Mbits/sec is delivered to the receiver using industry-standard IP protocols and MPEG-4 H.264 encoding identical to that used in the broadcast environment. This approach simplifies the development of receivers and ensures a minimum cost solution to the end user. In addition, relying on standard protocols and encoding methods ensures that the technology will have a suitably long product lifetime demanded for consumer electronics devices and will not be made obsolete by new technology as so often happens in the PC environment.
The MHEG-5 application has full control over the presentation of any streaming media and can provide control of the video either via on-screen controls using the basic remote control or through the playback keys on the remote control if they are present.
The MHEG-IC employs a number of levels of security, all relying on a “Broadcaster Trust” model. Certificates for secure HTTP connections are delivered over the broadcast transmission and can easily be updated. Applications delivered via the IP connection must be digitally signed and checked with a certificate delivered over-the-air to the receiver, protecting users from inappropriate content in the event of the internet server being hi-jacked. In addition, an approved server list provided in the broadcast carousel identifies which servers may be accessed by the receiver. The MHEG-IC does not support standard web browsing using HTML and Java Script, but provides a TV-centric presentation of content with a standard TV remote control user interface.
With the availability of the MHEG-IC in both set-top boxes, iDTVs and PVRs, broadcasters and content owners are now able to offer a whole new range of interactive services based on both the “push” and/or “pull” service models. Receivers with storage capacity (i.e. PVRs, iDTVs with built-in HDDs) potentially enable content to be pushed and stored onto the receiver via the broadcast/IP connection. Additional content can be requested by the consumer via the “pull” mechanisms offered by the IP connection. Broadcasters are now able to deploy applications such as home shopping, voting, enhanced programme guides, pushVoD, CatchUp TV (streaming-based or storage-based), targeted advertising etc.