Interactive television (iTV) can be defined as the result of the process of convergence between television and the new interactive digital technologies (Pagani, 2000a; 2000b; 2003). Interactive television is basically domestic television boosted by interactive functions that are usually supplied through a ‘back channel.’ The distinctive feature of interactive television is the possibility that the new digital technologies give the user to interact with the content that is on offer (Flew, 2002; Owen, 1999; Pagani, 2000a; 2000b; 2003). The evolution towards interactive television has not an exclusively technological, but also a profound impact on the whole economic system of digital broadcaster—from offer types to consumption modes, and from technological and productive structures to business models. This article attempts to analyze how the addition of interactivity to television brings fundamental changes to the broadcasting industry. The article first defines interactive transmission systems and classifies the different services offered according to the level of interactivity determined by two fundamental factors such as response time and return channel band. After defining the conceptual framework and the technological dimension of the phenomenon, the study analyzes the new types of interactive services offered. The Interactive Digital Television (iDTV) value chain will be discussed to give an understanding of the different business elements involved.
A Definition Of Interactivity
The term interactivity is usually taken to mean the chance for interactive communication among subjects (Pagani, 2001, 2003). Technically, interactivity implies the presence of a return channel in the communication system, going from the user to the source of information. The channel is a vehicle for the data bytes that represent the choices or reactions of the user (input). This definition classifies systems according to whether they are diffusive or interactive (Figure 1).
The classification of communication systems
Diffusive systems are those which only have one channel that runs from the information source to the user (this is known as downstream);
Interactive systems have a return channel from the user to the information source (this is known as upstream).
There are two fundamental factors determining performance in terms of system interactivity: response time and return channel band.
The more rapidly a system’s response time to the user’s actions, the greater is the system’s interactivity. Systems can thus be classified into:
Indirect interactive systems when the response time generates an appreciable lag from the user’s viewpoint;
Direct interactive systems when the response time is either very short (a matter of a few seconds) or is imperceptible (real-time).
The nature of the interaction is determined by the bit-rate that is available in the return channel (Rawolle & Hess, 2000). This can allow for the transfer of simple impulses (yes–no logic), or it can be the vehicle for complex multimedia information (i.e., in the case of video conferencing). From this point of view, systems can be defined as asymmetrically interactive when the flow of information is predominantly downstream. They can also be defined as symmetrical when the flow of information is equally distributed in the two directions (Huffman, 2002).
Based on the classification of transmission systems adopted above, multimedia services can be classified into diffusive (analog or digital) and interactive (Table 1).
Key Terms in this Chapter
Interactive Television: Defined as domestic television boosted by interactive functions, made possible by the significant effects of digital technology on television transmission systems. It supports subscriber-initiated choices or actions that are related to one or more video programming streams.
Value Chain: As made explicit by Porter in 1980 a value chain can be defined as a firm’s co-coordinated set of activities to satisfy customer needs, starting with relationship with suppliers and procurement, going through production, selling and marketing, and delivering to the customer. Each stage of the value chain is linked with the next stage, and looks forward to the customer’s needs, and backwards from the customer too. Each link of the value chain must seek competitive advantage: it must be either a lower cost than the corresponding link in competing firms, or add more value by superior quality or differentiated features (Koch, 2000).
Interactivity: Usually taken to mean the chance for interactive communication among subjects. Technically, interactivity implies the presence of a return channel in the communication system, going from the user to the source of information. The channel is a vehicle for the data bytes that represent the choices or reactions of the user (input).
Set-Top Box: The physical box that is connected to the TV set and the modem/cable return path. It decodes the incoming digital signal, verifies access rights and security levels, displays cinema-quality pictures on the TV set, outputs digital surround sound, and processes and renders the interactive TV services.
Decoder: See Set-top Box.
Multimedia Service: A type of service which includes more than one type of information (text, audio, pictures, and video), transmitted through the same mechanism and allowing the user to interact or modify the information provided.