An optical network is described that has a first ROADM node, a second ROADM node, and an optical transmission line establishing optical communication between the first ROADM node and the second ROADM node. The optical transmission line including an in-line amplifier node having a total input power and a total output power. The in-line amplifier node has a first monitoring tool configured to measure input optical power of the in-line amplifier node, and a second monitoring tool configured to measure output optical power of the in-line amplifier node. A software defined L0 network controller has circuitry configured to receive the optical power measured by the first and second monitoring tools from the in-line amplifier node, and to configure at least one of a gain and a gain tilt of the in-line amplifier node.

This disclosure describes devices and methods related to multiplexing optical data signals. A method may be disclosed for multiplexing one or more optical data signals. The method may comprise receiving, by a dense wave division multiplexer (DWDM), one or more optical data signals. The method may comprise combining, by the DWDM, the one or more optical data signals. The method may comprise outputting, by the DWDM, the combined one or more optical data signals to one or more wave division multiplexer (WDM). The method may comprise combining, by the one or more WDM, the combined one or more optical data signals and one or more second optical data signals, and outputting an egress optical data signal comprising the combined one or more optical data signals and one or more second optical data signals.

Methods, systems, and optical power controllers are disclosed. Various problems caused by the use of a single L0 power controller in the prior art are addressed by using first and second L0 power controllers with the first L0 power controller managing first optical components with the optical network, and the second L0 power controller managing second optical components within the optical network.

Methods, systems, and optical nodes are disclosed. The problems caused by the time-consuming process of serial activation of optical nodes in a restore path are addressed by utilizing a controller that controls all optical nodes in a restore path, in a parallel fashion, for faster restoration of the restore path.

This disclosure describes devices and methods related to multiplexing optical data signals. A method may be disclosed for multiplexing one or more optical data signals. The method may comprise receiving, by a dense wave division multiplexer (DWDM), one or more optical data signals. The method may comprise combining, by the DWDM, the one or more optical data signals. The method may comprise outputting, by the DWDM, the combined one or more optical data signals to one or more wave division multiplexer (WDM). The method may comprise combining, by the one or more WDM, the combined one or more optical data signals and one or more second optical data signals, and outputting an egress optical data signal comprising the combined one or more optical data signals and one or more second optical data signals.

According to the present invention, there is provided apparatus for providing protection of an optical link. The apparatus comprises a first port for coupling to the optical link and a second port for coupling to a further optical link. The apparatus further comprises a third port configured to receive an upstream optical signal to be transmitted over the optical link, and to output a downstream optical signal received over the optical link. The apparatus further comprises protection switching apparatus operable to selectively couple the third port to the first port or to the second port. The apparatus further comprises modifying apparatus configured to modify the upstream optical signal, received at the third port, before it is output from the first port, such that the switching upstream optical signal has a distinctive physical characteristic. The apparatus further comprises detecting apparatus, coupled between the first port and the third port, configured to receive a portion of an incoming optical signal, received at the first port, and to selectively detect the presence of the upstream optical signal or the downstream optical signal in the portion of the incoming signal based on the distinctive physical characteristic. The apparatus further comprises control circuitry configured to provide a control signal to the protection switching apparatus based on an output from the detecting apparatus.

An optical network communication system includes an optical hub, an optical distribution center, at least one fiber segment, and at least two end users. The optical hub includes an intelligent configuration unit configured to monitor and multiplex at least two different optical signals into a single multiplexed heterogeneous signal. The optical distribution center is configured to individually separate the at least two different optical signals from the multiplexed heterogeneous signal. The at least one fiber segment connects the optical hub and the optical distribution center, and is configured to receive the multiplexed heterogeneous signal from the optical hub and distribute the multiplexed heterogeneous signal to the optical distribution center. The at least two end users each include a downstream receiver configured to receive one of the respective separated optical signals from the optical distribution center.

This disclosure describes devices and methods related to multiplexing optical data signals. A method may be disclosed for multiplexing one or more optical data signals. The method may comprise receiving, by a dense wave division multiplexer (DWDM), one or more optical data signals. The method may comprise combining, by the DWDM, the one or more optical data signals. The method may comprise outputting, by the DWDM, the combined one or more optical data signals to one or more wave division multiplexer (WDM). The method may comprise combining, by the one or more WDM, the combined one or more optical data signals and one or more second optical data signals, and outputting an egress optical data signal comprising the combined one or more optical data signals and one or more second optical data signals.

The present invention relates to an optical network element (30, 34) comprising a wavelength selective switch, WSS, (432, 136) with one or more input ports, a working output port (38) and a separate protecting output port (40), the WSS (432) being configurable to a working configuration, in which one or more channels are routed from said one or more input ports to the working output port (38), and being configurable to a protecting configuration, in which said one or more channels or a subset thereof are routed from said one or more input ports to the protecting output port (40), or with a working input port (42) and a protecting input port (44) and with one or more output ports, the WSS (136) being configurable to a working configuration, in which one or more channels are routed from the working input (42) port to the one or more output ports, and being configurable to a protecting configuration, in which one or more channels are routed from the protecting input port (44) to the one or more output ports, a computer readable medium including program code defining configuration information, a control unit configured to control the WSS (432, 136) to adopt the working configuration or the protecting configuration based on the predefined configuration information.

An optical communication system includes a plurality of optical system nodes, a plurality of optical space switches and a plurality of optical fibers. The plurality of optical system nodes each includes at least one reconfigurable optical add/drop multiplexer (ROADM). The optical system nodes each have at least one client side port and at least one line side port. Each optical space switch is operatively coupled to the line side port of one of the plurality of optical system nodes. Each of the optical fibers couples one of the optical space switches to another of the optical space switches.