NO136231B

1453895 Automatic exchange systems SIEMENS - ALBIS AG STANDARD TELEPHON UND RADIO AG and HASLER AG 18 Jan 1974 [19 Jan 1973] 02489/74 Heading H4K A telecommunication system includes a switching network comprising at least two groups of parallel sections, each section having its own control unit and wherein the control units of each group share a common store individual to that group. The telephone network shown comprises two groups G1, G2 of three parallel sections E1 to E6 each including a network DNW1 to DNW6 controlled by a processor P1 to P6. Each group can connect to any subscriber associated with the network and each processor has access to a store SP1 or SP2 containing data such as the subscribers numbers, class of service data, short number lists, call forwarding and concentrator related information and functioning as a metering store. Each section deals normally with the calls from a section of the subscribers of its group but the networks are cross-connected at QV to allow any section to take over work of any other section of its group during fault conditions or to route a call via another section during overflow conditions. Lines from concentrators or large PBXs are distributed uniformly over the sections of a group.