Lucent Technologies Inc.

At&t Bell Laboratories

American Telephone & Telegraph Co., At&t Bell Laboratories

At+t Corp.

Ciena Corporation

At&t Laboratories, Limited

Anthony L Lentine

Ted Kirk Woodward

David A Miller

Gaylord W Richards

Thomas J Cloonan

Harvard S Hinton

Frederick B McCormick, Jr

Ashok V Krishnamoorthy

Leo M Chirovsky

Martin C Nuss

Giorgio Giaretta

John R Erickson

Jack L Jewell

Joseph Earl Ford

Stephen Joseph Hinterlong

Brandon C Collings

Frank K Hwang

Jurgen Jahns

Miles J Murdocca

Michael E Prise

Richard G Rozier

Jonathan Anderson Fields

Graham Smith

Nina L Taranenko

Dhritiman Banerjee

Graham H Smith

A data transmission system that detects fiber faults receives a plurality of data packets carried on a plurality of Gigabit Ethernet links at a plurality of Gigabit Ethernet input/output ports. The system then multiplexes, on a bit by bit basis, the data packets onto an optical link. When the system detects a loss of signal in one of the Gigabit Ethernet links, a signal loss code insert is generated. The system then multiplexes the signal loss code insert with the data packets.

Propagation and detection of faults in a multiplexed communication system

A method of data communication that includes receiving a plurality of 8b/10b encoded data streams. The method also includes multiplexing, on a word by word basis, each of the plurality of data streams and forming a new encoded data stream. The method also includes generating an interleaved encoded data stream substantially similar to an 8b/10b encoded spectrum from the new encoded data stream.

Word Multiplexing of encoded signals into a higher bit rate serial data stream

A module that includes both an 'add-in'/'drop-out' pair of ports and a &#x201c;drop-in&#x201d;/&#x201c;add-out&#x201d; pair of ports comprises an arrangement of elements that combines an optical signal having a chosen wavelength with an optical signal applied at the &#x201c;add-in&#x201d; port, and outputs the combined signal at the &#x201c;add-out port.&#x201d; Concurrently, the module extracts an optical signal with the same wavelength from an optical signal applied at the &#x201c;drop-in&#x201d; port signal, yielding an optical signal at the &#x201c;drop-out&#x201d; port that is missing that same wavelength. When the amount of information that needs to be sent from a first network node to a second, remote, node, is greater than that which a single wavelength can handle, a plurality of the above-described modules are interconnected within the first node by optically coupling the &#x201c;add&#x201d; ports in a &#x201c;daisy chain&#x201d; fashion and the &#x201c;drop&#x201d; ports in a &#x201c;daisy chain&#x201d; fashion, with each module operating at a different wavelength.

Stackable WDM arrangement

A reconfigurable ADD/DROP multiplexer/demultiplexer apparatus is implemented by connecting a multiplexer/demultiplexer apparatus to a serializer/deserializer (SERDES) apparatus having a loop-back capability. By selectively activating the loop-back functionality of the SERDES apparatus the combination can be made to function as a reconfigurable ADD/DROP multiplexer/demultiplexer apparatus.

Reconfigurable ADD/DROP, multiplexer/demultiplexer using a transceiver with loop-back function

A synchronization circuit including a plurality of samplers, the plurality of samplers sampling an input signal with a plurality of respective clock signals and producing a plurality of respective sampled output signals. The synchronization circuit also includes at least one phase detector coupled to the plurality of samplers, the at least one phase detector determining whether the plurality of sampled output signals are different and producing at least one control signal, the at least one control signal indicating whether the plurality of sampled output signals are different. In addition, the synchronization circuit includes a delay adjuster coupled to the at least one phase detector, the delay adjuster adjusting a delay of the input signal according to the at least one control signal output by the at least one phase detector.

Digital phase synchronization circuit

A method and associated apparatus for embedding control information in a data signal to be transmitted over a data link by a network node includes the generation of control information to be transmitted over a data link by a network node. Additionally, a transmission signal is generated by combining the control information with data to be transmitted. In an embodiment of the present invention, the data is transmitted within a prescribed frequency bandwidth such that a frequency gap is defined within the frequency bandwidth. Control information is, as such, transmitted within the defined frequency gap.

Method and apparatus for transport of control information over a data link

A system for data communication receives more than one input data streams that have independent clocks and an input order. The system synchronizes the input data streams to a common clock, and multiplexes the synchronized data streams onto an input of a data communication link. The system demultiplexes one or more output data streams from an output of the data communication link. The system identifies each of the output data streams and reorders the output data streams into the same order as the input data streams.

Data flow synchronization and ordering

A method and associated apparatus for embedding control information in a data signal to be transmitted over a data link by a network node. The method comprises generation of control information to be transmitted over a data link by a network node. A signal is generated by combining the control information with the data. In a first embodiment, the data includes individual temporal packets of information such that an interpacket gap is temporally defined between said temporal packets of information. Control information is transmitted within the interpacket gap. In a second embodiment, the data is transmitted within a prescribed frequency bandwidth such that a frequency gap is defined within the frequency bandwidth. Control information is transmitted within the frequency gap. The data handling capacity of the control information is maintained in both the first and the second embodiments.

A system for data transmission and communication receives a plurality of Gigabit Ethernet data packets from multiple Gigabit Ethernet links. The system bit multiplexes the data packets, on a bit by bit basis, together onto a fiber optic link. At the output of the fiber optic link, the bits are demultiplexed into data packets and transmitted onto multiple Gigabit Ethernet links. The high speed fiber optic link transmits the data at higher speed than is possible over each individual Gigabit Ethernet link.

Bit multiplexing of packet-based channels

A switch, of the crossbar type, in which no clock recovery is undertaken. Multiple optical fibers deliver input signals to a single semiconductor die. The die contains circuitry which selectively connects each input fiber to a respective output fiber, which carries the signals off the die, to their destinations. The communication is asynchronous: no continuous clock signal accompanies the incoming data. However, periodic sequences of clock signals accompany the incoming data, and are used by circuitry on the die in &ldquo;clock recovery&rdquo; routines, to generate local clock signals. The invention eliminates the need for local clock recovery: the incoming signals are routed through the die to outgoing fibers, without generation of a local clock signal on the die.

Asynchronous transfer of high speed data signals through an optoelectronic VLSI switch

A method for use in a data transmission system comprises the steps of: (i) adding timing information to a serial data stream; (ii) recovering the timing information from the serial data stream to generate a plurality of clock signals associated with the timing information, each clock signal having a common frequency and a different phase associated therewith, the common frequency being less than a frequency associated with the serial data stream; and (iii) converting the serial data stream to a plurality of parallel data streams respectively using the plurality of clock signals. The timing information may be added to the serial data stream at a data transmitter portion of the system. The invention provides for various ways to add the timing information to the serial data stream, i.e., enrich the serial data stream with the timing information. This timing information is preferably phase locked to the data and has a frequency less than the serial data transmission rate. Recovery of this lower speed timing information, e.g., clock tones, may be performed via filtering and phase aligning the timing information to generate the plurality of clock signals. Conversion of the serial data stream to the plurality of parallel data streams may then include using the clock signals to respectively sample or de-multiplex the serial data stream to yield the plurality of parallel data streams. The parallel data streams have a clock rate lower than that associated with the received serial data stream.

Data transmission system employing clock-enriched data coding and sub-harmonic de-multiplexing

An optical demultiplexer demultiplexes an N channel multiplexed optical data signal, at a first data rate, into N signal data channels. The demultiplexing is provided by N optical receivers, each receiver receiving a clock signal and the multiplexed optical data signal which is demultiplexed into a different one of the N signal data channels. In another embodiment, a shared photodetector converts the received multiplexed optical data signal into a multiplexed data signal which is then used by all of the N receivers.

Demultiplexing with clocked optical receivers

An optical fiber compatible modulator device provides high-contrast levels switchable using modest applied voltages. As a two-port optical modulator, a normal light signal incident at a first port is deflected to a non-normal direction for passage through an absorption layer (e.g., a multiple-quantum well (MQW) layer), the absorption layer having an adsorption characteristic which changes as a function of a voltage applied across it. The non-normal direction light signal exiting the absorption layer is deflected to a normal light signal for output from a second port of the optical modulator. As a one-port optical modulator, a normal light signal received at a first port is deflected to a non-normal direction for passage through an absorption layer. A reflector reflects a non-normal direction light signal exiting the layer back through the layer to the deflector means and is output at the port of the optical modulator.

Retro-reflecting electroabsorption optical modulators

An optical receiver apparatus and method for receiving optical signals and for generating output signals is disclosed. In particular, a photoconductor is illuminated with a preset beam before an input beam is incident on a detector to reset an input FET. An optical receiver according to the invention controls the voltage swings and the allowed voltages at the input stage, and can be monolithically integrated to allow uniform operation across a semiconductor chip and between circuits on different chips.

Apparatus and method for referencing an optical receiver

An optical receiver, e.g., receiver 10 (FIG. 1), has differential optical input beams and generates an electrical output. The voltage at an electrical node between series-connected optical detector diodes is clamped within a predefined voltage range by series-connected clamping diodes, to prevent the voltage from increasing when consecutive logic one optical input beams are received. Variable bandwidth and low energy dissipation are achieved since the resistors of high input impedance and transimpedance receivers are not required. A second optical receiver, e.g., receiver 20 (FIG. 2) is a monolithic, diode-clamped S-SEED with complementary optical input beams and complementary optical output beams.

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St. Charles, IL, United States of America

Anthony L Lentine