The CCIR considering a) that data broadcasting services are growing rapidly in number and diversity of application; b) that the media used to convey data broadcasting services now covers the whole gamut of broadcast emission bearers from LF radio through to SHF satellite systems; c) that the reducing cost of computing equipment makes the development of complex receiving terminals economically viable; d) that there will be an increasing need to interconnect broadcast transmission and reception equipment to computer networks and other data broadcasting equipments; e) that a method needs to be found to ease standardization and facilitate smooth evolution of data broadcasting systems in the future; f) that it is desirable to encourage the development of compatible interface specifications to rationalize the design of equipment.