Infinera Corporation

Foundry Networks, Inc.

Saurabh Kumar

Sanjeev Ramachandran

Baranidhar Ramanathan

Omer Faruk Yilmaz

Abhijeet D Deore

Parveen Kumar Gupta

Biao Lu

Rajan Rao

Nikhil Kumar Satyarthi

Parthiban Kandappan

Ganesh Sundaresan

Ankur Neog

Stephane St Laurent

Rama Kant Pathak

Brian Shia

Benjamin A Warren

Jaijo Jose

Walid El-Taki

Systems, methods, and devices for adding an alien or native wavelength optical signal to a fiber optic line. A portion of a spectrum of the fiber optic line corresponding to the optical signal is blocked with a wavelength selective switch (WSS). The portion of the spectrum is gradually unblocked until a power of the optical signal measured after the WSS is equal to a predetermined level. If the power and characteristics of the optical signal after the WSS satisfy one or more criteria, the portion of the spectrum is further unblocked until the power of the optical signal measured at the output is equal to an operational level.

System and method to add alien wavelength channels to optical line system

A method of many-to-one auto-discovery between modules includes: a source (sender) module sends the same source-ID on all its connected ports (many). The module may not know on which port the ID is sent. A sink (receiver) module is capable of receiving IDs on its port (one). The sink port identifies the association-ID (AID) of one end of the association (between sender and receiver). The association may be established based on each module discovering the sink AID of the sender in both directions (bi-directional). Both directions may be required for the source signal to get received on a respective sink. The source signal may be sent asynchronously in each direction.

Systems and methods for many-to-one bi-directional auto-discovery

This disclosure relates to optical line system equipment, which enables wavelength addition for long haul transmission. The system is configured to prevent contention of wavelengths added into a multiplexer. For example, an optical wavelength combiner, such as a multiplexer, may include components that are configured to detect potential collisions between existing wavelengths and a newly added wavelength, and block the addition of the conflicting wavelength while alerting the operator.

Wavelength collision detection in carrier multiplexers

A method for receiving, by circuitry of an optical node adapted for wavelength multiplexing and wavelength switching, over an OSC an optical signal comprising overhead information indicative of status of at least one of an optical layer in an OTN; terminating the optical signal; notifying software of the status of the optical layer; detecting, based on the status of the optical layer, a uni-directional or bi-directional failure of a working path between the optical node and a second optical node, wherein the working path carries data traffic from the first optical node to the second optical node in the OTN when there is no failure in the working path; and switching, triggered by the uni-directional or bi-directional failure of the working path, to select the data traffic from a protection path, wherein the protection path carries data traffic between the optical node and the second optical node.

Methods and systems for recovery in coherent optical networks

A device may perform a set of sample measurements of a set of slices of spectrum utilized by an input optical signal. The device may perform an analysis of the input optical signal to determine an attenuation profile. The analysis may include identifying a channel in a particular slice of spectrum, of the set of slices of spectrum, based on an optical power of a sample measurement, of the set of sample measurements, satisfying a threshold. The device may apply the attenuation profile to the input optical signal to generate an output optical signal with a particular spectral shape. The device may provide the output optical signal with the particular spectral shape.

Wavelength selective switch (WSS) for shaping optical signals

Consistent with the present disclosure, an optical amplifier is provided that is configurable in one of two modes. In both modes, the optical service channel (OSC) may be dropped and converted to an electrical signal. In the first mode, the electrical signal is subject to further processing and the monitoring and/or control information carried by the OSC may be updated with new data. Such updated monitoring and control information is then supplied to an OSC transmitter and modulated onto an OSC output from the optical amplifier. In a second mode of operation ('loop back' mode), however, the monitoring and/or control information bypasses the processing noted above is looped back to the OSC transmitter unchanged. Accordingly, OSC monitoring and control information or data can be rapidly passed through the optical amplifier with little delay. Moreover, the optical amplifier may be configured to operate in either the first or second modes by appropriately configuring a switch. Thus, a standard optical amplifier can be used as a both a line amplifier, in which OSC data is processed and updated, as well as a booster amplifier in which such updating does not occur, for example, but the OSC data may be propagated to other amplifiers with little delay.

Optical amplifier

Consistent with the present disclosure, a method and apparatus for providing a uniform spectral gain of an optical amplifier is provided. Namely, a 'balancing' step is carried out in which an optical channel having the lowest power level input to an optical circuit, such as an dynamic gain equalizer (DGE), is assigned a zero 'attenuation error' and is substantially un-attenuated by the DGE. The lowest power level optical signal does not require further attenuation and effectively serves as a reference power level, which the power levels of the remaining optical signals are set to. For example, remaining optical signals are assigned either positive or negative attenuation errors relative to the zero attenuation error based on optical signal input powers to the DGE and accumulated DGE attenuations over time. Those optical signals having a negative attenuation error are substantially unattenuated by the DGE, because such optical signals are adequately attenuated and do not require further attenuation. On the other hand, the DGE is controlled to attenuate those optical signals having positive attenuation errors to thereby flatten the output spectrum of the amplifier. In one example, interpolation techniques may be employed to control those portions of the DGE (e.g., attenuators or pixels) that do not receive a channel, such that adjacent pixels that receive channels may impart a desired amount of attenuation. In addition, further interpolation may be provided to appropriately control the DGE pixels, if the number of channels supplied to the DGE is different than the number of pixels of the DGE.

Apparatus and method for controlling a dynamic gain equalizer

In a network, packets are fragmented into head and non-head fragments. Non-head fragments are saved up front at an entry point, while a network switch forwards only the head fragment to Layer 4-Layer 7 (L4-L7) features for processing. The switch records changes that are performed on the head fragment's fields by the L4-L7 features while they process the head fragment. At an exit point, fields of the saved non-head fragments are overwritten with information that was recorded for the head fragment. This can include updating or modifying the source and destination parameters of the non-head fragments in an intelligent manner by reusing the results of the packet processing that was performed on the head fragment. This fragmentation handling technique avoids having to redundantly process the non-head fragments in the same manner as the head fragments.

Growing community of inventors

Menlo Park, CA, United States of America

Saurabh Kumar