At&t Intellectual Property I, L.p.

Att Knowledge Ventures, L.p.

Philip Wisseman

Martin Birk

Bruce Gilbert Cortez

Simon S Zelingher

Kathleen Tse

Aswatnarayan Raghuram

Paul Greendyk

James H King

Qingyun Liu

Sherry L McCaughan

A reconfigurable optical add-drop multiplexer (ROADM) transport network comprising a plurality of optical fan-out devices and a first plurality and a second plurality of demultiplexers for locally dropping selected wavelengths; and first plurality and a second plurality of multiplexers for locally adding selected wavelengths, the first and second plurality disposed in a cascaded relationship to enable selective coupling between network degrees.

Methods for expanding cross-connect capacity in a ROADM optical network

Additional bandwidth is provisioned to layer 2/3 networks by initially provisioning optical wavelength channels to meet incremental needs for additional capacity. When bandwidth requirements grow large enough, a wavelength-sized channel is provisioned to meet the bandwidth needs, and the previously provisioned optical wavelength channels are freed up to be reused for additional growth. The optical wavelength channels may be channelized VLANs mapped to resizable optical channel data units such as ODUflex units.

Layer 1 fast provisioning and right sizing of bandwidth for layer 2/3

A system and method for limiting the impact of an unstable wavelength on other wavelengths in a reconfigurable optical add/drop multiplexer (ROADM) network are disclosed. The method generally comprises measuring optical channel power at prescribed time intervals; for each measurement of channel power falling outside a predefined threshold, recording a threshold crossing event; comparing the recorded threshold crossing events to stored criteria indicative of an unstable wavelength channel; and removing an unstable wavelength from the ROADM network if the threshold crossing events exceed the stored criteria.

Mechanism to detect an unstable wavelength channel and limit its impact on a ROADM network

A system and method for dynamically adding/dropping wavelengths in a reconfigurable optical add-drop multiplexer (ROADM) transport network to form a wave division multiplexing virtual private network is disclosed. The system includes at least one optical transponder, a plurality of optical fan-out devices, each arranged to receive an input signal from a network degree and coupled to at least one of a plurality of optical fan-in devices, each optical fan-in device arranged to output a signal to a network degree, the optical fan-out devices comprising at least one wavelength selective switch and the optical fan-in devices comprising at least one wavelength selective switch, the optical fan-out devices and optical fan-in devices being connected so as to enable signals input from each of the plurality of network degrees to be switched to another network degree of the plurality of network degrees; a plurality of demultiplexers for locally dropping selected wavelengths; a plurality of multiplexers for locally adding selected wavelengths; and at least one customer-dedicated fiber switch interposed between the at least one optical transponder and the plurality of demultiplexers and multiplexers. The fiber switch is coupled to wavelengths and degrees that are allocated for a bandwidth-on-demand application. Other configurations include additional fan-in and fan-out devices interposed between a mux/demux assembly and the optical transponders to support wavelength redistribution applications.

Dynamic wavelength service over a ROADM optical network

A system and method for dynamically adding/dropping wavelengths in a reconfigurable optical add-drop multiplexer (ROADM) transport network is disclosed. The system includes at least one optical transponder, a plurality of optical fan-out devices, each arranged to receive an input signal from a network degree and coupled to at least one of a plurality of optical fan-in devices, each optical fan-in device arranged to output a signal to a network degree, the optical fan-out devices comprising at least one wavelength selective switch and the optical fan-in devices comprising at least one wavelength selective switch, the optical fan-out devices and optical fan-in devices being connected so as to enable signals input from each of the plurality of network degrees to be switched to another network degree of the plurality of network degrees; a plurality of demultiplexers for locally dropping selected wavelengths; a plurality of multiplexers for locally adding selected wavelengths; and at least one fiber switch interposed between the at least one optical transponder and the plurality of demultiplexers and multiplexers. The fiber switch is coupled to wavelengths and degrees that are allocated for a bandwidth-on-demand application. Other configurations include additional fan-in and fan-out devices interposed between a mux/demux assembly and the optical transponders to support wavelength redistribution applications.

Methods for dynamic wavelength add/drop in a ROADM optical network

A system and method for dynamically adding/dropping wavelengths in a reconfigurable optical add-drop multiplexer (ROADM) transport network is disclosed. The system includes a plurality of M&#xd7;N wavelength selective switches (WSS) for locally dropping selected wavelengths at a node, where each M&#xd7;N WSS has M inputs connected to optical fan-out devices in each of M network degrees, and a plurality of M&#xd7;N wavelength selective switches for locally adding selected wavelengths to a node, where each M&#xd7;N WSS has M outputs connected to optical fan-in devices in each of M network degrees. Several expedients of M&#xd7;N wavelength selective switches comprising M switching elements for use in the system are also disclosed.

Shared, colorless add/drop configuration for a ROADM network using M&#xd7;N wavelength switches

A system and method are disclosed for monitoring a fiber optic network between a managed location and a remote location. In a particular embodiment of the method the monitoring wavelength signal is separated from the communication wavelength signal at the remote location and coupled on to the optical fiber carrying a communication wavelength signal from the remote location. In a particular embodiment of the system, the system includes a first optical filter for coupling a selected monitoring wavelength signal on to an optical fiber carrying a communication wavelength signal between the managed location and the remote location and a second optical filter at the managed location for recovering a permanently separated monitoring wavelength signal sent to the managed location from the remote location.

Growing community of inventors

Austin, TX, United States of America

Philip Wisseman