The Service List Registry is an authoritative source of service lists enabling the discovery of audiovisual media services using the DVB-I specification.
A service list is an ordered list of audiovisual media services. These services can be traditional television or radio services, online media streams, or links to applications that offer access to audio and video on demand. A service list can include any combination of these.
A list has inherent order, with a set sequence of services to assist with selection. This intrinsically supports priority, which can also be indicated with prominence information.
Although a list is ordered, it does not imply any particular form of presentation. It does not impose vertical presentation in a column with up and down selection, although this may be conventional. A list can also support horizontal presentation in a row with left and right selection, or in a grid with directional selection. It could allow other forms of spatial navigation in three dimensions. However it is presented, the list should be presented in order as this is important for user familiarity.
A service can be associated with a number to enable direct numeric selection and navigation. This is important for established media brands that may have a strong association with a particular number. These logical channel numbers are well established in traditional broadcasting. The service list enables this to be extended to online services.
The numbering is in numeric order but not necessarily consecutive. There can be gaps in the sequence. The numbers must be positive integers of up to five digits. This means they can be memorable and easily selected. They will be unique in the context of a specific list. Some numbering schemes may assign different genres or types of service to particular numeric ranges for ease of organisation and selection.
A service has one or more service instances that correspond to different formats or modes of delivery. These may be specified in the service list in order of priority. A device, display or application can use this information to determine the appropriate instance to present according to its capabilities and user preferences. It may also fail over to an alternative instance if one becomes temporarily unavailable.
The registry maintains service lists but is not necessarily responsible for the assignment or allocation of services or service numbers in a service list. The composition and any numbering may be determined by a regulatory authority, an industry organisation, or a registered platform operator.
The Service List Registry provides a secure management interface to enable authorised parties to administer the configuration of service lists and service instances.