DVB-DATA (Data broadcasting)

Introduction

The DVB System provides a means of delivering MPEG-2 Transport Streams (TS) via a variety of transmission media. MPEG-2 TSs were primarily intended for the delivery of Video and Audio. The present document introduces data broadcasting as an extension to the MPEG-2 based DVB transmission standards.

Five different application areas with different requirements for the data transport are addressed. For each application area a data broadcasting profile is specified in the present document. The following is a short description of the application areas and the profiles.

Data piping:

• The data broadcast specification profile for data pipes (as defined in clause 4) supports data broadcast services that require a simple, asynchronous, end-to-end delivery of data through DVB compliant broadcast networks.

Data streaming:

• The data broadcast specification profile for data streaming supports data broadcast services that require a streaming-oriented, end-to-end delivery of data in either an asynchronous, synchronous or synchronized way through DVB compliant broadcast networks.
• Asynchronous data streaming is defined in clause 5 and allows the streaming of data without any timing requirements (e.g. RS-232 data).
• Synchronous data streaming is defined in clause 6 and allows the streaming of data with timing requirements in the sense that the data and clock can be regenerated at the receiver into a synchronous data stream.

Multiprotocol encapsulation:

• The data broadcast specification profile for multiprotocol encapsulation (as defined in clause 7) supports data broadcast services that require the transmission of datagrams of communication protocols via DVB compliant broadcast networks.
• Clause 8 further defines a standard mechanism for signalling IP/MAC services deployed within DVB networks and enables the implementation of DVB receivers that are completely self-tuning when accessing IP/MAC streams on one or more transport streams.
• Mechanisms for power-optimized reception and forward error correction for multiprotocol encapsulation are defined in clause 9.

Data and object carousels:

• Data broadcast services that require the periodic transmission of data are called data carousels, and are defined in clause 10.
• Object carousels (as defined in clause 11) are based on data carousels, and provide an additional hierarchical structure and further metadata, such as for example needed to build a hierarchical file system.

Higher protocols based on asynchronous data streams:

• The data broadcast specification profile for higher protocols (as defined in clause 12) is based on asynchronous data streams, and supports the transmission of protocols that require a stream-oriented delivery of asynchronous data through DVB compliant broadcast networks.

Scope

The present document specifies transport and encapsulation protocols, and signalling for carrying general purpose data over DVB Transport Streams. The present document is designed to be used in conjunction with ETSI EN 300 468.

Data broadcasting is an important extension of the MPEG-2 based DVB transmission standards. Examples are the download of software over satellite, cable or terrestrial links, the delivery of Internet services over broadcast channels (IP tunnelling), interactive TV, etc.