ISDN terminal portability in the RBOC networks

The differences in the initial ISDN switch implementations by different manufacturers are sufficiently profound that ISDN telephones designed for one switch may not be compatible with other manufacturers' switches. In addition, as new features are added to a given switch, older telephones may not be able to use them. The author examines two solutions to these problems: Bellcore-specified ISDN interfaces and programmable terminals. Bellcore-specified ISDN interfaces are desired by the Regional Bell Operating Companies and support considerable portability. Although conformance to Bellcore specifications will produce a high degree of terminal portability, it is unlikely ever to produce full portability and will not produce any portability in 1990. Programmable terminals are shown to offer interesting potentials for portability and extensibility.<
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