Ключевые слова:
Telecommunication, Telecommunication links, Telecommunication systems, Communication networks, Information exchange, Signal processing, Data transmission, Signal transmission, Messages, Telephone networks, Message switching networks, Communication procedures, Data handling, Error correction, Coding (data conversion), Conformity, Instructions for use, Identification methods, Addresses (data processing), Flow charts, Private integrated services network, Private networks, PINXs, Protocols