Keywords:
Blank forms, Calls, Characteristics, Communication equipment, Communication networks, Communication service, Communications, Conformity, Connection lines, Definitions, Digital signals, ETSI, Identification, Implementation, Integrated services digital network, Interfaces, Interfaces (data processing), ISDN, Line connections, Protocol implementation conformance statement, Records, Service definition, Signal transmission, Signalling systems, Supplementary services, Telecommunication, Telecommunication networks, Telecommunication systems, Telecommunications, Telephone networks, Telephone technics, Terminal devices, Test series, Test suites, Testing requirements, Transmission protocol