Nortel Networks Corporation

Tellabs Operations, Inc.

Xros, Inc.

Rockstar Consortium US LP

Robert R Ward

Rajiv R Ramaswami

Ornan A Gerstel

Humair Raza

Babu O Narayanan

Osama S Aboul-Magd

Mark E Boduch

Robert William Keys

Chris R Zettinger

Steven M Clark

Frederic J Simard

Vasant Sahay

David Park

Yong-Qin Chen

Rani Indaheng

Steven T Tabaska

Automatic discovery and verification of optical communication links as well as isolation of link failures in an optical communication system.

Link discovery, verification, and failure isolation in an optical communication system

A system supports 50 ms protection switching times independent of network architecture. The system includes multiple protection switch fabrics to perform facility protection switching for the signals and a central switch fabric to switch a subset of the signals in a non-facility protection switching manner among the protection switch fabrics. Linear and ring network configurations are supported by the system. The system has flexibility to perform Linear Automatic Protection Switching (LAPS), Unidirection Path Switched Ring (UPSR) protection switching, and Bidirectional Line Switched Ring (BLSR) protection switching without burdening the central switch fabric with unnecessary or redundant traffic.

Apparatus and method for protection switching in a network

A way of testing a wavelength division multiplexed (WDM) system without requiring connection to data source/sink equipment. A test signal is introduced onto a light path of interest in the system, and the test signal is monitored downstream for signal integrity. Lack of signal integrity is used to identify a fault in the lightpath. Alternatively, optical loopbacks may be used to localize and identify a fault in the lightpath. The lightpath includes a source optical node connected to a sink optical node via intermediate optical nodes. An optical signal introduced at the source node with a destination at the sink node may be looped back at any one of the intermediate nodes or the sink node to localize and identify a fault in the lightpath.

Optical network connection test apparatus and methods

Apparatus and methods are disclosed for alignment of an input mirror and an output mirror in a photonic cross-connect.

Alignment laser for use in cross-connects

A method for calibrating a preferred disposition for a moveable first mirror of an optical switch core of a photonic crossconnect device relative to a second mirror thereof, the method comprising the steps of determining approximate geometric coordinates of the first mirror relative to the second mirror, effecting a laser light crossconnection between the first and second mirrors to produce data from which to provide first order corrections to refine the geometric coordinates, and effecting a further laser light crossconnection between the first mirror and a third mirror, to produce data from which to provide second order corrections to further refine the geometric coordinates, whereby to calibrate the first mirror such that upon initiation of a laser light crossconnection involving the first mirror, a switching element detects deviation of the first mirror from the preferred disposition thereof and effects corrective changes.

Method for calibrating photonic crossconnect device

Methods, apparatus and systems for regenerating, monitoring and bridging optical signals through an optical cross-connect switch to provide increased reliability. A self testing method, apparatus and system for an optical cross-connect switch. An optical-to-electrical-to-optical converter (O/E/O) is provided in an optical cross-connect switch to provide optical-electrical-optical conversion. I/O port cards having an optical-to-electrical-to-optical converter are referred to as smart port cards while I/O port cards without an optical-to-electrical-to-optical converter are referred to as passive port cards. Test port/monitor cards are also provided for testing optical cross-connect switches. Methods, apparatus and systems for performing bridging, test access, and supporting redundant optical switch fabrics are also disclosed.

Signals and methods for increasing reliability in optical network equipment

Method and apparatus for regenerating optical signals in an all-optical cross-connect switch

Method and apparatus for bridging optical signals in an optical network

Method and apparatus for optical to electrical to optical conversion in an optical cross-connect switch

In one embodiment, a scalable cross-connect switching system and its corresponding method perform a bridging operation by splitting the incoming light signal into at least a first bridged light signal and a second bridged light signal. The first bridged light signal has a power level equal to or substantially greater than a power level of the second bridged light signal. The disproportionate power levels provide low-loss bridging. Light signals based on these bridged light signals are routed through multiple switch fabrics which provide redundancy in case of failure by switching within the switch fabric. To detect failures, a test access port is configured for monitoring multiple optical paths.

Optical cross-connect switching system with bridging, test access and redundancy

In general, an optical cross-connect switching system comprising a switch subsystem, an input/output (I/O) subsystem including a plurality of removable, I/O port modules, and a switch control subsystem featuring servo modules. These units collectively operate to provide optical data paths for routing of light signals without conversion from optical to electrical domains and back to optical. Also, the optical cross-connect switching system is scalable because the I/O port modules, servo modules and even features of the switch subsystem may be removed without disruption in system operation.

Growing community of inventors

St. Charles, IL, United States of America

Robert R Ward