The term interactive television, Interactive Television (ITV), is used for services that require consumer interaction at the home television set. In interactive television such as Enhanced TV( ETV), the consumer interacts with the broadcaster. For such interaction, a transmission channel must be created from the consumer to the broadcaster, since television is broadcast, namely from the broadcaster to the consumer.
The telephone and the telephone network can be used as a transmission channel from the consumer to the broadcaster. This makes it possible, for example, to call the broadcasting station for business TV. More modern concepts of digital TV provide for digital return channels.
In the case of distribution services on television, a distinction is made between services with interaction and call services. The first group of interactive services includes all demand services, such as tele-commerce, teleshopping, telelearning, telebanking, video games, video-on-demand or information-on-demand. Call services include video services such as pay-per-view, pay-per-channel or near-video-on-demand.
Interactive television uses a television with a set-top box as the end device. Interaction takes place via the return channel, which, depending on the concept, can be implemented via the telephone, a modem or, in the case of digital TV, via the system-specific return channels DVB-RCC, DVB-RCS and DVB-RCT.