How will these new applications be implemented?
Contained with in the MHP standard is a proposed DVB-HTML which is based on XML but has it's own DOM and doctype declaration.
What does this mean for Content Providers, Web authors?
So as to obey the DVB commercial requirement on rejection of non-conformant content by MHP implementations, DVB-HTML requires the "validation" of any documents that are signalled (in the broadcast stream or the file itself) as being of the DVB-HTML application type.
Reading from the above this means that any internet documents accessed by the MHP system have to comply with and validate against the DVB-HTML DTD or they will be rejected. However the DVB-HTML language complies with the XHTML Modularisation W3C Recommendation, so the step for most should not be too great.
Because the adoption of a single standard world-wide for the application of interactive television has not been done, DVB-MHP is only one of the current standards being developed. This may mean that there will be regional differences in the standard used to display internet information on digital networks. If an application is to be developed (i.e. an e-commerce site) that requires a broad audience then it will require browser sniffing to identify if the user is using DVB-MHP, ATSC, DAVIC, or a standard internet browser. And subsequent redirection or dynamic writing of the page will be required.
The second article in this series will examine the DTD requirements and the modules included, excluded and added for DVB-HTML.