E VRT: Interactive television pilot in Flanders
The Flemish government also launched about 100 pages of its Internet site in a TV
centric form, including interactive applications like online requests for information
and searching for jobs. Also the local community of Schoten created a television
friendly website for its citizens, which makes all kinds of practical information
available with attractive and user friendly layout and navigation for the television
2.4. Content delivery processes
The DHP pilot uses the DVB T technology (Digital Video Broadcast Terrestrial). It
is a digital aerial transmission standard. The signals are transmitted in MPEG 2,
compressed thus, since the available frequency spectrum is limited (from 2 to 15
MB/s). Cable and satellite have a higher capacity but they allow only stationary
reception. DBV T is available everywhere. It is suited to mobile reception as well.
Many TV stations, in Europe and worldwide are implementing or experimenting with
Other advantages of DBV T are, according to Peter Suetens, related to lower
transmission costs. For one tenth of the price of upgrading the existing cable
network in Flanders, we are able to install enough DBV T transmitters to cover the
whole of Flanders and then we could watch high quality TV in the car. Moreover, as
a public broadcaster using DBV T, we are able to provide a real alternative to cable
and satellite transmission. We need to provide access for all. For this reason, I don t
understand why the BBC has sold its transmission installation. Now they need to
negotiate access to different platforms with various partners. By having your own
transmission network, you are more independent and that is what we value. Another
advantage is that each new user does not cost us anything more .
It is crucial to note that although the DHP is about interactive TV, the content
delivery process is still based on a push model. Broadcasters continue to push their
content (data, sound, video, text, etc.), but towards the hard drive of the set top
box rather than directly towards the viewers. The model is also described as local
storage . It is a way to create virtual bandwidth since the DBV T bandwidth is
smaller compared to cable and satellite. For users, local storage has the advantage
of instant play. Technically, this is not easy since everything needs to be tagged or
addressed, otherwise users can not re find the content .
Given the bandwidth restriction of DBV T, it takes time to download TV programmes
onto the set top box. Live programmes like the evening news can be viewed live but
are, at the same time, placed on the hard drive. About one hour after they are
broadcast live, they are available for viewing whenever you want. During the day
and the night, the VRT places different TV programmes on the hard drive. News
items can also be updated and/or enriched with additional content.
To deal with prime time transmission overload, it might be envisaged in the future
that the Electronic Program Guide (EPG) can be accessed on a mobile platform (e.g.
PDA). You could then, during lunch for instance, indicate the programmes you would
like to see during the evening, enabling the broadcaster to download them onto the
set top box hard drive in the afternoon, during off peak times .