GB1482537A - Automatic telephone exchanges - Google Patents

Abstract

1482537 Self-steering networks PLESSEY CO Ltd 28 Oct 1975 [11 Dec 1974] 53528/74 Heading H4K A telecommunications switching centre includes data-processing equipment (DPE) for overall management and control purposes and has a multi-stage switching network of selfsteering cross-bar switches, Figs. 1-4 (not shown), which provide access to outgoing junction routes (ORK-ORN). First and second stage switches are link-connected to form a plurality of identical first routers (RTR), each of which has a transmission relay group (TRG, Fig. 5, not shown), which terminates an incoming junction, provided at each inlet. The first and second stages of each router are provided with first and second interface equipments (ASIX, BSIX) for communication with the central data-processing equipment. Each additional switching stage is similarly provided with an interface equipment (CSIX, DSIX), while a plurality of such equipments (JIX) serve the junction relay sets (ORS, Fig. 8, not shown) of all the outgoing routes. Each interface equipment includes a scanner and a distributer for respectively transmitting information to and receiving instructions from the DPE, while each first interface equipment (ASIX) additionally includes a sensing device (SX) responsive to the effective backward marking of an outlet of any first-stage switch of the corresponding router. In responding, the sensing device brings about via the appropriate interface equipments and the DPE, operation of that bridge magnet relating to the router inlet of a calling TRG, followed by stage-by-stage operation of all the bridge magnets necessary to set up a connection through the network from the calling TRG to the marked outgoing junction relay set.