specifies how the trigger messages defined in IEC 62297-1 are transmitted. A trigger is defined as information sent from a service provider as part of a data broadcasting transmission that initiates an application in a receiver. Additional information in the trigger message allows filtering or prioritization techniques to be applied at the receiver. Examples of possible use include the forcing of the display of information to warn of severe weather conditions and advising of extreme content in the TV programme. In an interactive system, a message or icon might be displayed inviting on-line access to vote, to register an interest in an advertised product, or to browse programme-related content