All optical processing circuit for conflict resolution and switch configuration in a 2×2 optical node

Abstract

An optical processing circuit, such as a combinatorial network, comprises an arrangement of optical logic gates suitable for use in combination with a switched optical node of the kind having at least first and second input ports and two output ports, the node being configurable into either a cross or a bar configuration, and in which the optical processing circuit is arranged so as to receive at least three optical input signals which respectively comprise a packet identifier signal PIH which identifies whether or not a first input signal is present at the first input port of the switched optical node, the first input port being assigned a higher priority than the second input port, a first destination address AH indicating the output port of the switched optical node to which a first information carrying signal, received at the first input port, is intended to be passed, and a second destination address AL indicating the output port of the switched optical node to which a second information carrying signal, received at the second input port, is intended to be passed, and in which the processing circuit is configured to generate from these three optical input signals the following optical output signals: a contention resolution control (CRC) signal which has a first value if a routing conflict is present and a second if it is not; and a switch control generation (SCG) signal indicating whether the associated switched optical node is to be set in a cross or bar configuration.