1.1 General Standards of the EN 50083 series deal with cabled distribution systemsnetworks for television signals, sound signals and interactive multimedia signalsservices including equipment, systems and installations • - for headend -reception, processing and distribution of television and sound and television signals and their associated data signals and • - for processing, interfacing and transmitting all kinds of signals for interactive multimedia signalsservices using all applicable transmission media. They cover aAll kinds of systemsnetworks like • - CATV-systemsnetworks, • - MATV-networks and SMATV-systemsnetworks, • - iIndividual receiving systemsnetworks and all kinds of equipment, systems and installations installed in such systemsnetworks, are within this scope. The extent of theseis standardsization work is from the antennas, special signal source inputs to the headend or other interface points to the systemnetwork up to the system outlet or the terminal input, where no system outlet exists. The standardization of any user terminals (i.e. tuners, receivers, decoders, multimedia terminals etc.) as well as of any coaxial and optical cables and accessories therefor is excluded. 1.2 Specific scope of this part 9 This standard describes physical interfaces for the interconnection of signal processing devices for professional CATV/SMATV headend equipment or for similar systems, such as in uplink stations. Especially this document specifies the transfer of DVB/MPEG-2 data signals in the standardized transport layer format between devices of different signal processing functions. RF interfaces and interfaces to telecom networks are not covered in this document. In addition references are made to all other parts of EN 50083 series (Cabled distribution networks systems for television signals, and sound signals and interactive services) and in particular for RF, video and audio interfaces to part 5: \'Headend equipment“. For connections to telecom networks a special Data Communication Equipment (DCE) is necessary to adapt the serial or parallel interfaces specified in this document to the bitrates and transmission formats of the public Plesiochronic Digital Hierarchy (PDH) networks. Other emerging technologies such as Connectionless Broadband Data Services (CBDS), Synchronous Digital Hierarchy (SDH), Asynchronous Transfer Mode (ATM) etc. can be used for transmitting MPEG-2 Transport Streams (TS) between remote locations. ATM is particularly suitable for providing bandwidth on demand and it allows for high data rates.