An intelligence-defined optical tunnel network system includes pods. Each pod includes optical add-drop sub-systems. Each optical add-drop sub-system includes a first transmission module and a second transmission module. The first transmission modules of the optical add-drop sub-systems are connected to each other for forming a first transmission ring. The second transmission modules of the optical add-drop sub-systems are connected to each other for forming a second transmission ring. Each first transmission module includes a multiplexer and an optical signal amplifier. The multiplexer is connected to a Top-of-Rack switch. The multiplexer is configured to receive, through input ports, upstream optical signals from the Top-of-Rack switch, and combine the upstream optical signals into a composite optical signal. The upstream optical signals have wavelengths respectively. The optical signal amplifier, coupled to the multiplexer, is configured to amplify the composite optical signal and output an amplified composite optical signal.

Signal distribution arrangements are assembled by selecting a terminal body and a tap module combination that provides the desired signal strength at the intended position in an optical network. Each terminal body includes an input connection interface, a pass-through connection interface, a module connection interface, and multiple drop connection interfaces. Each tap module houses an optical tap having an asymmetric split ratio. Most of the optical signal power received at the signal distribution arrangement passes to the pass-through connection interface. A portion of the optical signal power is routed to the drop connection interfaces (e.g., via a symmetrical optical power splitter). The tap module and terminal body combination are selected based on the desired number of drop connection interfaces and to balance the asymmetric split ratio with the symmetric split ratio.

An optical add/drop device (100) comprising: a common port (102); an add port (106); a first wavelength selective optical filter (110) configured to: receive an optical signal at an add wavelength from the add port and transmit said optical signal at the add wavelength towards the common port; and receive optical signals from the common port and reflect optical signals not at the add wavelength; a second wavelength selective optical filter (114) configured to receive said optical signals from the common port reflected by the first wavelength selective optical filter and transmit an optical signal at a drop wavelength, different to the add wavelength; a drop port (116); and an optical waveguide (118) configured receive said optical signal at the drop wavelength transmitted by the second wavelength selective optical filter and route said optical signal to the drop port.

A control apparatus includes an optical wavelength change control unit that specifies, in response to a request to change a wavelength band of a first optical wavelength path used by a first transmission apparatus and a second transmission apparatus to a wavelength band of a second optical wavelength path, a first route between routers which is affected by the request and a service which uses the first route and that specifies a second route between the routers which detours the specified service; a router control unit that transmits a request to detour the specified service to the second route, to a start-point router and an end-point router on the first route; and a transmission apparatus control unit that transmits a request to change the wavelength band of the first optical wavelength path to the wavelength band of the second optical wavelength path, to the first transmission apparatus and the second transmission apparatus.

An optical add-drop apparatus dropping a signal in input optical fibers in an optical cross-connect apparatus or adding a signal into output optical fibers from the cross-connect apparatus, optical cross-connect portions of the cross-connect apparatus connected such that a cross-connect portion internal connection output port is directly connected to an internal connection input port of another cross-connect portion and is indirectly connected via the other cross-connect portion to an internal connection output port of a further cross-connect portion, the add-drop apparatus having: photocouplers connected to part or all of the input fibers connected to each cross-connect portion; and drop signal receiving apparatuses each having optical switches each receiving and alternately selecting a signal output from photocouplers connected to respective different cross-connect portions of the cross-connect portions out of the photocouplers, the drop signal receiving apparatuses selecting a signal of a wavelength for each signal respectively output from the optical switches.

Components of an optical communications network are described at a node of the network providing switching from one or more degrees of received optical signal routed to a plurality of receivers. The switch at the node generally includes a passive reconfigurable optical add drop multiplexer (ROADM) having drop or output ports that connector to optical channels leading to optical receivers without optical amplifiers between the ROADM outputs and the receivers. Configurations of the node and corresponding parameters are described that provide for use of lower cost components due to the absence of an array of optical amplifiers connected to the ROADM outputs.

An optical add/drop device (100) comprising: a common port (102); an add port (106); a first wavelength selective optical filter (110) configured to: receive an optical signal at an add wavelength from the add port and transmit said optical signal at the add wavelength towards the common port; and receive optical signals from the common port and reflect optical signals not at the add wavelength; a second wavelength selective optical filter (114) configured to receive said optical signals from the common port reflected by the first wavelength selective optical filter and transmit an optical signal at a drop wavelength, different to the add wavelength; a drop port (116); and an optical waveguide (118) configured receive said optical signal at the drop wavelength transmitted by the second wavelength selective optical filter and route said optical signal to the drop port.

Signal distribution arrangements are assembled by selecting a terminal body and a tap module combination that provides the desired signal strength at the intended position in an optical network. Each terminal body includes an input connection interface, a pass-through connection interface, a module connection interface, and multiple drop connection interfaces. Each tap module houses an optical tap having an asymmetric split ratio. Most of the optical signal power received at the signal distribution arrangement passes to the pass-through connection interface. A portion of the optical signal power is routed to the drop connection interfaces (e.g., via a symmetrical optical power splitter). The tap module and terminal body combination are selected based on the desired number of drop connection interfaces and to balance the asymmetric split ratio with the symmetric split ratio.

The present invention is to provide a wavelength cross-connect device that reduces device costs.

A wavelength cross-connect device 10B performs relaying for changing, using WSSs, routes of optical signals transmitted from M routes 1h to Mh, in which K optical fibers 1f to Kf are grouped for each of the routes, on an input side to output the optical signals to respective optical fibers 1f to Kf of M routes 1h to Mh on an output side. Input ports of each of the optical couplers 25a to 26d are connected to output ports of each of first WSSs 21a to 22k. Further, the input ports of each of the optical couplers 25a to 26d are connected to the output ports of the first WSSs 21a to 22k and output ports of each of the optical couplers 25a to 26d are connected to input ports of second WSSs 23a to 24k such that the optical signals input from the optical fibers 1f to Kf in each of the routes 1h to Mh on the input side are capable of being output to the optical fibers 1f to Kf in each of the routes 1h to Mh on the output side, respectively.

The present invention is to provide an optical add/drop multiplexing device capable of realizing a configuration in which many transponders can be connected at low cost.

An optical add/drop multiplexing device 30A includes branch function units 34a to 34d connected to each of WSSs 22a to 22d connected to respective routes 1 to D having a plurality of optical fibers and dropping optical signals having a plurality of wavelengths among the optical signals having the respective wavelengths transmitted by wavelength division multiplexing. The optical add/drop multiplexing device includes C-function units 35a to 35d configured to transmit the optical signals branched by the branch function units 34a to 34d to a plurality of transponders. The optical add/drop multiplexing device includes optical couplers 36a to 36d each connected between a set of K WSSs 22c and 22d each having 1 input and M outputs and one of the branch function units 34a, K being a number of 2 or more, the number of optical couplers being equal to or greater than a positive integer obtained by dividing a numerical value D(M−D) by K, the numerical value being obtained by multiplying the number (M−D) of optical signals dropped by each of the WSSs 22c and 22d by the number D of all of the WSSs 22a to 22d. The optical coupler 36a couples optical signals of different wavelengths dropped by a set of WSSs into one optical signal and outputs the coupled optical signal to the branch function unit 34a.