Plans for a public data network in Sweden

At the Central Administration of Swedish Telecommunications, a study of a national public data network has been completed. The network is aimed at accommodating subscriber data-transmission speeds up to 9600 bits/s. The study shows that the network shall be of the synchronous type utilizing circuit-switching techniques with a connection time on the order of 100-200 ms. It shall provide means for accommodating both synchronous and asynchronous subscriber terminal equipment. In the former case, the information flow to and from the subscriber shall be transmitted within a fixed format synchronized by the network. In the latter case the asynchronous data flow shall be converted to a synchronous data flow at a concentrator. Concentrators shall be connected to exchanges via 64-kbit/s time-division multiplexing (TDM) data channels, whereas exchange interconnections shall be via TDM data channels with speeds up to 2.048 Mbits/s. A public data network gives possibilities for: introducing new services; standardizing operational and maintenance network routines; standardizing subscriber procedures; traffic with other public data networks; simplifying customer network buildup; integration with other types of telecommunications. A trial network will be built up in order to test principles and hardware for the public data network.