Optical network systems and components are disclosed including a transmitter comprising a digital signal processor receiving a plurality of independent data streams, the digital signal processor supplying outputs based on the plurality of independent data streams, the digital signal processor comprising a plurality of pulse shape filters corresponding to the plurality of independent data streams, the plurality of pulse shape filters configured to filter the independent data streams to produce a first subcarrier having a first frequency bandwidth and a second subcarrier having a second frequency bandwidth different than the first frequency bandwidth for the outputs.

The invention relates to a method for establishing a communication channel, preferably an embedded control channel, between a central network node and at least one network unit to be integrated in a communication network including the central network node and an arbitrary but limited number of network units. The central network node is adapted to create and output a wavelength-division multiplex (WDM) downstream signal including downstream channel signals to be transmitted to the network units and to receive a WDM upstream signal including upstream channel signals created by the network units.

We disclose an optical add-drop multiplexer that can apply different routing operations to different subcarriers of a data frame. In an example embodiment, the digital signal processor (DSP) of the optical add-drop multiplexer carries out subcarrier-specific add, drop, and pass-through operations in the electrical frequency domain, which enables the DSP to only partially unwrap the pass-through subcarriers, thereby at least partially avoiding some of the more processing-power-hungry DSP operations and reducing the sub-wavelength routing latency accordingly. Also disclosed is an example data-frame structure that can be used to provide subcarrier-specific routing instructions to the optical add-drop multiplexer.

A TORminator module is disposed with a switch linecard of a rack. The TORminator module receives downlink electrical data signals from a rack switch. The TORminator module translates the downlink electrical data signals into downlink optical data signals. The TORminator module transmits multiple subsets of the downlink optical data signals through optical fibers to respective SmartDistributor modules disposed in respective racks. Each SmartDistributor module receives multiple downlink optical data signals through a single optical fiber from the TORminator module. The SmartDistributor module demultiplexes the multiple downlink optical data signals and distributes them to respective servers. The SmartDistributor module receives multiple uplink optical data signals from multiple servers and multiplexes them onto a single optical fiber for transmission to the TORminator module. The TORminator module coverts the multiple uplink optical data signals to multiple uplink electrical data signals, and transmits the multiple uplink electrical data signals to the rack switch.

[Problem] whether optical input interruption detected by an OXC device is due to an external failure from an upstream side or an internal failure of the OXC device in a transponder device connected to the OXC device using an optical transmission line, and this determination is implemented at low cost.

[Solution] An optical transmission system (10A) is configured by connecting a plurality of OXC devices (14A) using optical fibers (16) between transponder devices (15A1) that relay optical signals transmitted to/from terminals (19a, 19b). The OXC device (14A) includes an OSC part (4d1) and a monitoring control part (4e1). The OSC part (4d1) outputs wavelength information on an optical signal in which optical input interruption has occurred and path information on a path of an optical fiber (16) in which the optical input interruption has occurred, at the time of detecting the optical input interruption from the optical fiber (16). In accordance with the wavelength information and the path information that have been output as above, the OXC device (14A) includes an AIS generation part (4j) that generates an AIS signal including both pieces of information on the wavelength and the path of the optical signal relating to the optical input interruption and alarm information relating to both the pieces of information.

This optical path setting device comprises: a transmission characteristic calculating means for calculating an inter-endpoint transmission characteristic that is a characteristic for transmission between endpoints of an optical path accommodating traffic in a plurality of optical communication systems; a required wavelength bandwidth determining means for determining a required wavelength bandwidth that is a wavelength bandwidth meeting an arrival performance of the optical path on the basis of the inter-endpoint transmission characteristic; and an accommodating wavelength band determining means for determining, as an accommodating wavelength band for accommodating the optical path, a common wavelength band that is a wavelength band where an optical path having the required wavelength bandwidth can be allocated, and that is common to the plurality of optical communication systems.

Optical protection switching apparatus (10), for a single fibre bidirectional WDM optical ring, comprising: first (12) and second (14) ports for coupling to first and second adjacent portions of a single fibre bidirectional WDM optical ring; an optical splitter (16) comprising an input to receive a WDM aggregate optical signal, and first and second outputs coupled to the first and second ports; an optical switch (108) between the second output and the second port; and processing circuitry (24) to receive at least one of an indication of transmission continuity in the optical ring and an indication of transmission discontinuity in the optical ring, and to generate a switch control signal (20) comprising instructions to cause the optical switch to be open when there is transmission continuity in the optical ring and to cause the optical switch to be closed when there is transmission discontinuity in the optical ring.

Constellations of distributors interconnect access nodes to form a vast contiguous network. The access nodes are generally geographically spread and the constellations are generally geographically spread, however the distributors within each constellation are collocated. The access nodes are arranged into access groups. The access nodes of each access group interconnect through selected constellations, with each access node having a wavelength-division-multiplexed (WDM) link to each of the selected constellations, to form a three-stage network. The three-stage networks corresponding to the access groups are mutually fused so that an access node of any three-stage network has multiple paths, each traversing one distributor, to each other access node of the same three-stage network and a path to each other access node of the entire network traversing one distributor. The distributors are preferable configured as fast optical switches. The network is structured to provide global coverage without the need for conventional cross-connectors.

Systems and methods include receiving Open Shortest Path First (OSPF) packets from a plurality of OSPF areas; sending self-generated OSPF packets to the plurality of OSPF areas; and filtering of the received OSPF packets such that received Link State Advertisement (LSA) packets from an OSPF area (are not forwarded to other OSPF areas. In an embodiment, the systems and methods can be used for a scalable OSPF deployment for management of a network, such as an optical network.

Embodiments of the invention describe apparatuses, optical systems, and methods for utilizing a dynamically reconfigurable optical transmitter. A laser array outputs a plurality of laser signals (which may further be modulated based on electrical signals), each of the plurality of laser signals having a wavelength, wherein the wavelength of each of the plurality of laser signals is tunable based on other electrical signals. An optical router receives the plurality of (modulated) laser signals at input ports and outputs the plurality of received (modulated) laser signals to one or more output ports based on the tuned wavelength of each of the plurality of received laser signals. This reconfigurable transmitter enables dynamic bandwidth allocation for multiple destinations via the tuning of the laser wavelengths.