Abstract: In a device for the transmission, by an asynchronous network, notably a network of the ATM type, of signalling data elements, channel by channel, assembled in a multiframe transmitted synchronously in out-of-band mode, the information elements are conveyed, in the asynchronous network, in packets of data bits, each, packet being formed by an information cell including, firstly, a header carrying an address and, secondly, a useful field carrying the information to be transmitted. On a transmission side, the device includes an apparatus for acquiring signalling data elements of each channel of the multiframe; a device to detect changes in the state of these data elements; and a device for the generation, on the network, at each change thus detected, of an information cell containing the new signalling data element and the address associated with the corresponding channel.

Abstract: A logic selection module for forming the interface between the two central units and eight selection circuits of an electronic time automatic telephone switchboard and which comprises means for selecting the calling central unit, means for connecting the thus selected central unit, means for decoding the address of one of the eight selection circuits to which the module is connected in the signal received from the thus selected central unit and means for transmitting the marking signals received from the central unit to the said circuit, whose address has been decoded.