integrated digital network
Integrated text and data network comprising Deutsche Telekom's public services(telex, teletex, Datex-L, Datex-P and Direktruf/HfD). The development of the network is marked by the introduction of ISDN. IDN was a pure data network, which increasingly merged into ISDN.
IDN has been built since 1974, contains EDS exchanges and integrates data services. All subscribers to IDN are connected via single or multiplex lines to one of the 23 data exch anges (DVST) available in the Federal Republic of Germany.
The IDN is based on the PCM30D system, which connects the EDS exchanges in this network. PCM30D provides a total of 30 data channels with transmission speeds of 64 kbit/s. These fast data streams are obtained from slower data streams of the subscriber terminals by time-division multiplex data transmission. This technique creates three hierarchy levels with output bit rates of 3 kbit/s, 64 kbit/s and 2.048 Mbit/s.