US companies are complaining that Nippon Telegraph and Telephone Corp’s specification of the Tron operating system as mandatory for its ISDN and digital switching network suppliers is a trade barrier against US firms hoping to bid for contracts. But NTT officials claimed that Tron was an open system, available for development by foreign as well as Japanese firms. However, the Japanese have now built up a long lead in Tron expertise because foreign companies ignored the operating system, dismissing it as an academic gizmo that would never fly in the commercial world. As a result, in the current joint development effort to build systems for Tron at NTT, Northern Telecom Ltd is the only outsider company. The others are Fujitsu Ltd, Hitachi Ltd, Matsushita Electric Industrial Co, Mitsubishi Electric Corp, NEC Corp, Oki Electric Co and Toshiba Corp. Nippon Telegraph plans to use Tron on its DEX digital network switching processor and in the ISDN interface subscriber module that is to be added to the existing D-70 public telephone exchange to provide ISDN support over analogue telephone networks, Electronic News reports from Tokyo. Nippon Telegraph has been experimenting with an implementation of Tron on Motorola 68000 family microprocessors, although these will not be used in the first versions of the new ISDN equipment.
