Abstract: A method of making conference call connections in computer-controlled telephone exchanges includes combining voice signals of conference participants on a digital basis, forming a signal of a total of speaking levels of a given number of the most active participants, distributing the signal in an undamped manner, and suppressing voice signals of the inactive participants. A bit stream of the conference participants reaching a conference assembly through an incoming line is distributed to m adding processors having n channels each, and the PCM words are linearized with a code table and stored in level memories for each particular participant. A total of the linear values is formed, is added to individual participant evaluation totals and is stored in evaluation memories for each particular participant. The participant evaluation totals are transmitted to an evaluation processor which determines active channels by using a delayed mean value of the participant levels and transmits it to the adding processors.

Abstract: A packet switching architecture in which switching network nodes automatically determine nonblocking paths through a switching network in response to address information. The switching network comprises stages of broadcast and routing nodes. The broadcast nodes are responsive to the transmission of address information from an input port to create a plurality of paths through the switching network and to communicate on this plurality of paths the address information to the routing stages. Each of the routing switch nodes is responsive to receipt of address information to select one of the paths to an address-designated output port. The final path is established by the output port transmitting an acknowledge signal back through the switching network. Each node upon receipt of the acknowledge signal establishes the path through the itself.