A wavelength cross connect device includes: a WXC unit including input-side WSSes and Output-side WSSes; and a wavelength band switching unit. Of wavelength multiplexed signal beams N-split by each input-side WSS, wavelength multiplexed signal beams in which optical signals for which wavelength band conversion is not necessary are multiplexed are input to the output-side WSSes. The wavelength band switching unit performs wavelength band conversion on, of the N-split wavelength multiplexed signal beams, a selected wavelength multiplexed signal beam in which optical signals for which wavelength band conversion is necessary are multiplexed, to generate a wavelength-band-converted wavelength multiplexed signal beam in which the wavelength bands of optical signals of distinct wavelength bands multiplexed in the wavelength multiplexed signal beam have been converted, and outputs the wavelength-band-converted wavelength multiplexed signal beam to one of the output-side WSSes so as to be rerouted.

An optoelectronic switch comprising: a first plurality of detector remodulators (DRMs) (C3, D1), each DRM having an integer number M of optical inputs and an integer number N of optical outputs; a second plurality of DRMs (C7, D5), each DRM having N optical inputs and M optical outputs; a passive optical switch fabric (C4+C5+C6, D2+D3+D4) connecting the N optical outputs of each of the first plurality of DRMs with the N optical inputs of each of the second plurality of DRMs, the path of an optical signal through the optical switch fabric depending upon its wavelength; wherein each DRM (C3, D1) of the first plurality of DRMs is configured to act as a tunable wavelength converter to select the desired path of an optical signal through the optical switch fabric (C4+C5+C6, D2+D3+D4); and wherein each of the first plurality of DRMs (C3, D1) includes a concentrator, the concentrator configured to aggregate optical signals received from any of the M inputs of that DRM and to buffer them according to the one of the plurality of second DRMs (C7, D5) that includes their destination port.

In some embodiments, a system includes a set of servers, a set of switches within a switch fabric, and an optical device. The optical device is operatively coupled to the set of servers via a first set of optical fibers. Each server from the set of servers is associated with at least one wavelength from a set of wavelengths upon connection to the optical device. The optical device is operatively coupled to each switch from a set of switches via an optical fiber from a second set of optical fibers. The optical device, when operative, wavelength demultiplexes optical signals received from each switch from the set of switches, and sends, for each wavelength from the set of wavelengths, optical signals for that wavelength to the server from the set of servers.

A wavelength cross connect device includes: a wavelength band switching unit configured to receive wavelength multiplexed signal beams each having been transmitted in multiple bands in optical transmission lines each including one or more optical fibers, the wavelength multiplexed signal beams each including multiplexed optical signals of distinct wavelength bands, perform wavelength band conversion on each of the wavelength multiplexed signal beams so as to convert the wavelength bands of the optical signals multiplexed in the wavelength multiplexed signal beam, and output the converted wavelength multiplexed signal beams; and a WXC unit including input-side WSSes that respectively split and output the wavelength multiplexed signal beams output from the wavelength band switching unit, and output-side WSSes mesh-connected to the input-side WSSes. The WXC unit inputs the split wavelength multiplexed signal beams to the output-side WSSes while performing rerouting and outputs the rerouted wavelength multiplexed signal beams to output transmission lines.

A spectral-temporal connector interconnects a large number of nodes in a full-mesh structure. Each node connects to the spectral-temporal connector through a dual link. Signals occupying multiple spectral bands carried by a link from a node are de-multiplexed into separate spectral bands individually directed to different connector modules. Each connector module has a set temporal rotators and a set of spectral multiplexers. A temporal rotator cyclically distributes segments of each signal at each inlet of the rotator to each outlet of the rotator. Each spectral multiplexer combines signals occupying different spectral bands at outlets of the set of temporal rotators onto a respective output link. Several arrangements for time-aligning all the nodes to the connector modules are disclosed.

Described herein are balanced, bidirectional, optical communication networks. These networks may be used in large-scale settings, including in networks including more than one hundred nodes or more than one thousands nodes. A network may include a plurality of nodes. Each node comprises a plurality of optical transceivers of a first type and a plurality of optical transceivers of a second type. The types differ from each other in a characteristic of light transmitted by the respective optical transceiver. The optical transceivers of the first type are in equal numbers across the plurality of nodes and the optical transceivers of the second type are also in equal numbers across the plurality of nodes. A plurality of optical channels connect the nodes with one another by coupling optical transceivers of the first type with optical transceivers of the second type. The optical channel support bidirectional communication between the connected nodes.

In some embodiments, a system includes a set of servers, a set of switches within a switch fabric, and an optical device. The optical device is operatively coupled to the set of servers via a first set of optical fibers. Each server from the set of servers is associated with at least one wavelength from a set of wavelengths upon connection to the optical device. The optical device is operatively coupled to each switch from a set of switches via an optical fiber from a second set of optical fibers. The optical device, when operative, wavelength demultiplexes optical signals received from each switch from the set of switches, and sends, for each wavelength from the set of wavelengths, optical signals for that wavelength to the server from the set of servers.

A spectral-temporal connector interconnects a large number of nodes in a full-mesh structure. Each node connects to the spectral-temporal connector through a dual link. Signals occupying multiple spectral bands carried by a link from a node are de-multiplexed into separate spectral bands individually directed to different connector modules. Each connector module has a set temporal rotators and a set of spectral multiplexers. A temporal rotator cyclically distributes segments of each signal at each inlet of the rotator to each outlet of the rotator. Each spectral multiplexer combines signals occupying different spectral bands at outlets of the set of temporal rotators onto a respective output link. Several arrangements for time-aligning all the nodes to the connector modules are disclosed.

Various example embodiments of optical nodes may be configured to support improved connectivity between optical fibers and/or cores of optical fibers connected to the optical nodes based on use of various optical cross-connect architectures within the optical nodes. Various example embodiments of optical nodes configured to support use of various optical cross-connect architectures within the optical nodes in order to provide improved connectivity within the optical nodes in a manner that supports improved connectivity between optical fibers and/or cores of optical fibers connected to the optical nodes may be configured to support optical cross-connect architectures that increase connectivity between middle stage switches of the optical nodes (e.g., use of an auxiliary optical switch to increase connectivity between middle stage switches, use of connections between middle stage switches to increase connectivity between middle stage switches, or the like, as well as various combinations thereof).

Multiple switch planes, each having meshed bufferless switch units, connect source nodes to sink nodes to form a communications network. Each directed pair of source and sink nodes has a first-order path traversing a single switch unit in a corresponding switch plane and multiple second-order paths each traversing two switch units in one of the remaining switch planes. To reduce processing effort and minimize requisite switching hardware, connectivity patterns of source nodes and sink nodes to the switch planes are selected so that each pair of source node and sink node connects only once to a common switch unit. Widely-varying flow rates may be allocated from each source node to the sink nodes. To handle frequent changes of flow-rate allocations, in order to follow variations of traffic distribution, a high-throughput scheduling system employing coordinated multiple scheduler units is provided in each switch plane.