Communications exchange

Claim 2

A tridundant telex communications exchange adapted for interconnection of a large number of subscriber lines and/or trunks each connected to a terminator in said exchange, and comprising: a. a switching network including said terminators and a plurality of electromechanical switches adapted to effectuate interconnection between selected terminators under computer control, b. three computers each including (1) a scanner distributor for communicating message processing data between said switching network and said computer, and (2) an input/output processor for communicating switch status and control signals between said switching network and said computer, and c. a system controller including redundant channels for forwarding message processing data and switch status and control signals between said switching network and said scanner distributors or input/output processors, and further including system mode control logic and, for each channel, majority logic cooperating to establish which computer or computers are communicating valid data, message processing data and control signals being forwarded only from such valid data communicating computer or computers.

Claim 3

In a communication system of the character described, the combination comprising: a. a switching network comprising a plurality of subscriber line terminators and a plurality of trunk terminators and switches operable to establish a large number of possible message transmission paths between said terminators, b. multiple computers operable simultaneously upon network transmitted message processing data to similarly process said data and to produce output data for controlling said switches to effectuate interconnection between selected terminators, each computer including a core memory and a central processing unit, c. a system controller through which communication of data between said switching network and said computers is established, and operable to determine which computers shall be preferred as communicating valid data and which of such preferred computers shall be used as sole survivor to transmit most reliable data to said switching network, d. a scanner distributor with each computer and operable on a time-dependent basis and in response to central processor controlled programming in core memory to communicate message processing data and terminator activity status between said terminators and said computers, for storage in the computer memories, and e. wherein said system controller includes certain like A and B channels each incorporating voting logic circuitry operable in conjunction with system mode control logic to select said preferred and sole survivor computers, said controller communicating the output data of the survivor computer scanner distributor to said switching network via both said A and B channels.

Claim 4

In a communication system of the character described, the combination comprising: a. a switching network comprising a plurality of subscriber line terminators and a plurality of trunk terminators and switches operable to establish a large number of possible message transmission paths between said terminators, b. multiple computers operable simultaneously upon network transmitted message processing data to similarly process said data and to produce output data for controlling said switches to effectuate interconnection between selected terminators, each computer including a core memory and a central processing unit, c. a system controller through which communication of data between said switching network and said computers is established, and operable to determine which computers shall be preferred as communicating valid data and which of such preferred computers shall be used as sole survivor to transmit most reliable data to said switching network, d. a scanner distributor with each computer and operable on a time-dependent basis and in response to central processor controlled programming in core memory to communicate message processing data and terminator activity status between said terminators and said computers, for storage in the computer memories, and e. wherein said system controller includes certain like A and B channels each incorporating voting logic circuitry operable in conjunction with system mode control logic to select said preferred and sole survivor computers, said controller communicating the output data of the survivor computer scanner distributor to said switching network via both said A and B channels.

Claim 5

The system of claim 2 wherein there are three of said computers.

Claim 6

In a communication system of the character described, the combination comprising: a. a switching network comprising a plurality of subscriber line terminators and a plurality of trunk terminators and switches operable to establish a large number of possible message transmission paths between said terminators, b. multiple computers operable simultaneously upon network transmitted message processing data to similarly process said data and to produce output data for controlling said switches to effectuate interconnection between selected terminators, each computer including a core memory, a central processing unit, c. a system controller through which communication of data between said switching network and said computers is established, and operable to determine which computers shall be preferred as communicating valid data and which of such preferred computers shall be used as sole survivor to transmit most reliable data to said switching network, d. input/output processor means with each computer and operable to transfer switch status and switch controlling output data between data storage means in the computer and said switching network, via said system controller, and e. wherein said system controller includes certain like A and B channels each incorporating voting logic operable in conjunction with system mode control logic to select said preferred and sole survivor computers, said computer operatively communicating the output data of the sole survivor computer input/output processor to said switching network.

Claim 7

In a communication system of the character described, the combination comprising: a. a switching network comprising a plurality of subscriber line terminators and a plurality of trunk terminators and switches operable to establish a large number of possible message transmission paths between said terminators, b. multiple computers operable simultaneously upon network transmitted message processing data to similarly process said data and to produce output data for controlling said switches to effectuate interconnection between selected terminators, each computer including a core memory, a central processing unit, c. a system controller through which communication of data between said switching network and said computers is established, and operable to determine which computers shall be preferred as communicating valid data and which of such preferred computers shall be used as sole survivor to transmit most reliable data to said switching network, d. input/output processor means with each computer and operable to transfer switch status and switch controlling output data between data storage means in the computer and said switching network, via said system controller, and e. wherein said system controller includes certain like A and B channels each incorporating voting logic operable in conjunction with system mode control logic to select said preferred and sole survivor computers, said computer operatively communicating the output data of the sole survivor computer input/output processor to said switching network.