A fully connectorized optic fiber tap assembly is described that includes a first upstream connector interface configured to receive a downstream connector of a first upstream optic fiber line, and a first downstream connector interface configured to receive an upstream connector of a first downstream optic fiber line. The tap assembly further includes a set of service drop line connector interfaces. Moreover, an optic fiber tap of the assembly is configured to: receive an optical signal from the upstream connector interface, extract a portion of the optical signal, direct the extracted portion of the optical signal to the set of service drop line connector interfaces, and pass a remaining portion of the optical signal to the downstream connector interface. The fully connectorized optic fiber tap assembly is configured to be connected to the first upstream optic fiber line and the first downstream optic fiber line without splicing.

An optical branching/coupling device includes: a first optical branching unit that splits first light with a first and a second wavelength, and outputs second light and third light; a wavelength selector that receives the second light, receives fourth light with a third wavelength, output fifth and sixth light, one of the fifth light and the sixth light including an optical signal of the first wavelength of the second light and including the fourth light, and the other including an optical signal of the second wavelength; a first light switch that receives the fifth light and the sixth light, output one of the fifth light and the sixth light as seventh light, and output the other as eighth light; and a second light switch that receives the third light, receives the eighth light, and outputs the third or the eighth light that have been input as ninth light.

An optical branching/coupling device includes: a first optical branching unit that splits first light with a first and a second wavelength, and outputs second light and third light; a wavelength selector that receives the second light, receives fourth light with a third wavelength, output fifth and sixth light, one of the fifth light and the sixth light including an optical signal of the first wavelength of the second light and including the fourth light, and the other including an optical signal of the second wavelength; a first light switch that receives the fifth light and the sixth light, output one of the fifth light and the sixth light as seventh light, and output the other as eighth light; and a second light switch that receives the third light, receives the eighth light, and outputs the third or the eighth light that have been input as ninth light.

This application provides an example light source switching apparatus. The apparatus includes first and second multi-mode interference (MMI) couplers, and a phase modulator. The first MMI coupler includes four ports, where first and second ports are located on one side, and third and fourth ports are located on the other side. The second MMI coupler includes three ports, where fifth and sixth ports are located on one side, and a seventh port is located on the other side. The first and the second ports connect to the fifth and the sixth ports, respectively, to form two connections. The phase modulator is disposed on one of the two connections, and the seventh port connects to an optical modulator. Both the third and the fourth ports connect to a light source emitting continuous light, and the phase modulator selects one of the two light sources for output from the seventh port.

Systems and methods include determining a defragmentation plan that changes a configuration of a network to move the network from a current state of operation to a new state of operation; updating any of the defragmentation plan and the new state of operation in response to an opportunity presented during operation of the network; and implementing one or more steps in the defragmentation plan based on the opportunity. The opportunity can be anticipated to occur at a future time and implementation of the one or more steps is conditioned on occurrence of the opportunity. For example, the opportunity can include any of a maintenance window, a network equipment change, a capacity change in the network, a change to demand in the network, an external event including weather, and changes in links in the network. Also, the opportunity can include a fault.

Systems and methods include determining a defragmentation plan that changes a configuration of a network to move the network from a current state of operation to a new state of operation; updating any of the defragmentation plan and the new state of operation in response to an opportunity presented during operation of the network; and implementing one or more steps in the defragmentation plan based on the opportunity. The opportunity can be anticipated to occur at a future time and implementation of the one or more steps is conditioned on occurrence of the opportunity. For example, the opportunity can include any of a maintenance window, a network equipment change, a capacity change in the network, a change to demand in the network, an external event including weather, and changes in links in the network. Also, the opportunity can include a fault.

A network element configured to operate in an Optical Transport Network (OTN) network includes one or more modules including a first regenerator port and a second regenerator port, wherein the one or more modules are configured to provide a Low Order (LO) regenerator function; and circuitry configured to detect the one or more modules are part of the LO regenerator function, and, responsive to detection of a fault on the first regenerator port, cause forward traffic conditioning at a High Order (HO) path to the second regenerator port. The forward traffic conditioning can include an Alarm Indication Signal (AIS) on the HO path.

A network element configured to operate in an Optical Transport Network (OTN) network includes one or more modules including a first regenerator port and a second regenerator port, wherein the one or more modules are configured to provide a Low Order (LO) regenerator function; and circuitry configured to detect the one or more modules are part of the LO regenerator function, and, responsive to detection of a fault on the first regenerator port, cause forward traffic conditioning at a High Order (HO) path to the second regenerator port. The forward traffic conditioning can include an Alarm Indication Signal (AIS) on the HO path.

An optical interface includes circuitry configured to operate the optical interface at a first rate, subsequent to a requirement to suberate the optical interface to a second rate, determine which services are affected, signal a partial failure for the one or more affected services, and operate the optical interface at a second rate that is less than the first rate. The optical interface can be a Flexible Optical (FlexO) or ZR interface.

An optical interface includes circuitry configured to operate the optical interface at a first rate, subsequent to a requirement to suberate the optical interface to a second rate, determine which services are affected, signal a partial failure for the one or more affected services, and operate the optical interface at a second rate that is less than the first rate. The optical interface can be a Flexible Optical (FlexO) or ZR interface.