... And because international traffic was relatively unimportant, and relatively insensitive to tariffs, it was not considered a major disadvantage if incompatibilities occur at frontiers, or with imported equipment. Indeed, calls across the EC's internal borders currently represent only some 5% of the total telephone revenue. | network ideas from europe -- the european community

public switched telephone network (PSTN), the public videotex networks, the packet switched data networks and the Integrated Services Digital Network (ISDN) ..."Transpac" (France Telecom), "IPSS" (British Telecom) and "DATEX-P" (Deutsche Bundespost)

osi reference model document: ISO/TC97/SC16, standard 7498, 1982; tc97 doesn't exist anymore nor sc16; ref maybe in ISO/IEC FDIS 9594-5 ...

available iso-standard papers | thanks for the pointer!

architel group: architel (for architecture for telecommunications; ISO 83 meeting the red book rfc806