A system and method for a tunable optical delay line. The tunable optical delay line comprises a coarse delay portion that provides a coarse delay amount, the coarse delay portion including a coarse delay selection element in conjunction with a coarse delay element, the coarse delay selection element incorporated on-chip into a photonic integrated circuit (IC) component, the coarse delay element being disposed off-chip of the photonic IC component and interconnected with the coarse delay selection element; and a fine delay element that provides a fine delay amount, the fine delay element interconnected in series with the coarse delay selection element, the optical delay line being tunable to a target delay amount by agglomerating the coarse and fine delay amounts.

Methods, systems, and apparatus, including an apparatus for generating clusters of building blocks of compute nodes using an optical network. In one aspect, a method includes receiving data specifying requested compute nodes for a computing workload. The data specifies a target arrangement of the nodes. A subset of building blocks of a superpod is selected. A logical arrangement of the subset of compute nodes that matches the target arrangement is determined. A workload cluster of compute nodes that includes the subset of the building blocks is generated. For each dimension of the workload cluster, respective routing data for two or more OCS switches for the dimension is configured. One-to-many switches are configured such that a second compute node of each segment of compute nodes is connected to a same OCS switch as a corresponding first compute node of a corresponding segment to which the second compute node is connected.

A wavelength selective optical switching arrangement (23) comprises a set of input ports (61), a set of output ports (65); a switching matrix; and a plurality of de-multiplexers each comprising an aggregate port (62) and a plurality of tributary ports (64), each aggregate port being connected to an input port and each tributary port being connected to the switching matrix (57), the switching matrix being coupled between the tributary ports and the output ports. The wavelength selective optical switching arrangement is configured to receive at an input port a group of optical signals, each optical signal being transmitted on a different wavelength and being assigned to one of a plurality of destination nodes. The wavelength selective optical switching arrangement is further configured to de-multiplex the group of optical signals in a said demultiplexer; re-group the optical signals into destination groups according to their destination node; and route each destination group to a respective output port assigned to the destination group.

A transmitting device, includes inputting a multiplex light multiplexed a first wavelength-multiplexed signal light stream in a first wavelength band and a second wavelength-multiplexed signal light stream in a second wavelength band; inputting a multiplex light multiplexed a third wavelength-multiplexed signal light stream in a first wavelength band and a fourth wavelength-multiplexed signal light stream in a second wavelength band; converting the first wavelength-multiplexed signal light stream to the second wavelength band; converting the third wavelength-multiplexed signal light stream to the second wavelength band; generating a first output signal light multiplexed by signal light in a first wavelength band among the multi-wavelength light so that wavelengths do not overlap; generating a second output signal light multiplexed by signal light in a second wavelength band among the multi-wavelength light so that wavelengths do not overlap; converting the first output signal light to the first wavelength band; and outputting the multiplexed light.

A method and apparatus for operating an optical switching fabric or other optical device are provided. The device has multiple input and output ports to be selectably connected together via optical paths. For a requested configuration, an optical device configuration is determined based on a loss metric, which is based on one or both of: a number of crossings of the optical paths; and a length of the optical paths. The crossings can be waveguide crossings within the switching fabric. The configuration can be obtained by selecting particular intermediate stages of the switching fabric for carrying particular optical paths. The number of waveguide crossings, or the variation in the number of waveguide crossings, can be limited or minimized in the selected configuration. In one embodiment, an initial solution is determined, and the intermediate stages of the switch are re-ordered to obtain an improved solution in terms of the loss metric.

Systems and methods to incrementally scale robotic software-defined cross-connects from 100 to more than 100,000 ports are disclosed. A system is comprised of individual cross-connect units that individually scale in increments of say, 96 interconnects in tier 1 to, for example, 1,008 interconnects total. A system comprised of multiple cross-connect units arranged and interconnected in a two-tier approach is disclosed, one which achieves fully non-blocking, any-to-any connectivity with the flexibility to grow incrementally. Methods to build out this system over time, in an incremental and non-service interrupting fashion, are described.

A method and apparatus for operating an optical switching fabric or other optical device are provided. The device has multiple input and output ports to be selectably connected together via optical paths. For a requested configuration, an optical device configuration is determined based on a loss metric, which is based on one or both of: a number of crossings of the optical paths; and a length of the optical paths. The crossings can be waveguide crossings within the switching fabric. The configuration can be obtained by selecting particular intermediate stages of the switching fabric for carrying particular optical paths. The number of waveguide crossings, or the variation in the number of waveguide crossings, can be limited or minimized in the selected configuration. In one embodiment, an initial solution is determined, and the intermediate stages of the switch are re-ordered to obtain an improved solution in terms of the loss metric.

In the examples provided herein, a system has a plurality of arrayed waveguide gratings (AWG) having a plurality of input ports and a plurality of output ports. A signal within a given wavelength channel transmitted to one of the input ports of a given AWG is routed to one of the output ports of the given AWG based on a signal wavelength. The system also has a plurality of nodes, with each node comprising a set of components for each AWG that the node is coupled to. Each set of components comprises a plurality of optical transmitters, where each optical transmitter is tunable over multiple wavelength channels within a different wavelength band; a band multiplexer to multiplex the multiple wavelength channels within each different wavelength band; and a first output fiber to couple an output of the band multiplexer to one of the input ports of a first AWG.

The present disclosure relates to registration methods and devices. One example method includes obtaining, by a line card, line card information of the line card, the line card comprising a fabric interface chip optically interconnected to a switch fabric chip in at least one switch fabric card by using an optical fiber, and sending, by the line card, the line card information to the at least one switch fabric card through an optical interconnect path. The at least one switch fabric card registers the line card based on the line card information.

Network devices and associated methods are provided for synchronization in an optically switched network. The network device includes one or more ports in communication with a plurality of devices via an optical switch. The one or more ports receive a master clock signal having a first frequency from a first device of the plurality of devices. The network device includes a local clock in communication with the one or more ports and operating at a second frequency. The network device includes a synchronization manager in communication with the one or more ports and the local clock and configured to be enabled and disabled. When the synchronization manager is enabled, it receives the master clock signal via the one or more ports and transmits an instruction to the local clock to operate at the first frequency.