SSH EN 300 708 V1.2.1:2003

Television systems; Data transmission within Teletext

Scope

The present document describes the various ways in which Teletext may be used to carry non-Teletext services. It
should be used in conjunction with EN 300 706 [1]. An example is fully described in EN 300 707 [2]. The present
document includes additional practical information on implementing a data service of this type.
Hooks into existing Teletext services may be provided from within the application which is carried as a non-Teletext
service. A data broadcast application may be pointed to from the Magazine Inventory Page (MIP) or it may be allocated
a specific page number. A Code of Practice (CoP) shall ensure that services destined for the consumer may be found
quickly by "low-end" Teletext decoders but this is outside the scope of the present document.
There are two methods available for carrying data services. The first method carries the data within Teletext pages. The
data in these pages is not suitable for direct display by a Teletext decoder and shall normally be allocated a special page
number and/or have the display inhibited. The second method carries the data within Independent Data Lines (IDL) and
these are independent of the page service.
With both Page and IDL formats there exist versions which offer Conditional Access (CA).
There are other specific IDL data services which have been defined but it is beyond the scope of the present document
to cover all of these.