Patents Assigned to Sycamore Networks, Inc.
  • Patent number: 8560552
    Abstract: The present application describes methods and systems for compressing and/or decompressing data. As blocks of data are processed, the processed blocks are placed into a circular buffer at a compressor and indexed based on patterns of data present in the processed blocks. A circular buffer is maintained at the decompressor so that the decompressor circular buffer is consistent with the compressor circular buffer. When a new block of data is processed, the compressor checks the index to the circular buffer to determine whether the new block of data contains a pattern that is redundant with a pattern in one or more blocks of data that have already been processed. If a redundancy is detected, the compressor informs the decompressor of the redundancy and provides information allowing the decompressor to reconstruct the redundant pattern from the decompressor's circular buffer. In this way, redundant data need not be retransmitted or stored.
    Type: Grant
    Filed: February 11, 2010
    Date of Patent: October 15, 2013
    Assignee: Sycamore Networks, Inc.
    Inventor: Mario Fortier
  • Patent number: 8514697
    Abstract: A method in an electronic device and a system for use in a communication network including a core network and at least one access network are described. Intermediate service platforms in an access network process data bound from a base station towards a core network, and vice versa. A first data channel or stream is processed by the intermediate service platform. Exemplary embodiments bypass the intermediate service platform by intercepting a second data channel or stream bound for the intermediate service platform. The data in the second data channel or stream is processed and inserted into a data channel or stream downstream of the intermediate service platform.
    Type: Grant
    Filed: January 8, 2010
    Date of Patent: August 20, 2013
    Assignee: Sycamore Networks, Inc.
    Inventors: Yang Cao, Michael Nicolazzo, William M. Turner, Talbot Hack, Moshe Suberri
  • Patent number: 8271610
    Abstract: A method in an electronic device provides local content to a user device in a communication network. The communication network includes an access network and a core network. In the access network, a content request is intercepted from the user device, which may be formatted according to a network interface. The content request may include a request for data content. Protocol layers associated with an active data session may be terminated so that an edge gateway device may extract and inject packets into the data stream without involving the core network. A cache may be maintained in the access network.
    Type: Grant
    Filed: March 5, 2009
    Date of Patent: September 18, 2012
    Assignee: Sycamore Networks, Inc.
    Inventors: Yang Cao, Michael Nicolazzo, William M. Turner, Talbot Hack, Moshe Suberri
  • Patent number: 7826345
    Abstract: Each span of a communication network, such as a BLSR ring, is assigned a unique span ID. When a node of the network detects a failure in a network span, the node exchanges commands, according to an automatic protection switching (APS) protocol, that request other nodes of the network to switch network traffic from a working span to a protect span. The commands specify the working span by its span ID, without necessarily specifying a source node ID or a destination node ID for the commands. The span ID occupies fewer bits in the commands than bits representing a combination of the source node ID and the destination node ID. Alternatively, the commands specify a destination node ID without a span ID or a source node ID, or the commands specify a source node ID without a span ID or a destination node ID.
    Type: Grant
    Filed: July 7, 2004
    Date of Patent: November 2, 2010
    Assignee: Sycamore Networks, Inc.
    Inventors: Anthony C. K. Kam, Raymond Y. Xie, Tao Yang, Naimish Patel
  • Patent number: 7050561
    Abstract: A method and apparatus are provided for the management of multiple-node networks to provide for efficient and rapid determination of an alternative connection path through the network to avoid a fault in the connection path. The present invention seeks to minimize the number of nodes affected by the alternative connection path by systematically seeking alternative, non-retracing connection paths from nodes neighboring the connection fault. Until an alternative connection is found, searches are conducted from nodes further from the connection fault. Optionally, the present invention may use a retracing path to establish a connection.
    Type: Grant
    Filed: July 19, 2001
    Date of Patent: May 23, 2006
    Assignee: Sycamore Networks, Inc.
    Inventor: Raymond Yinggang Xie
  • Patent number: 7012887
    Abstract: A method and apparatus for restoring a diversely routed circuit in a timely manner from an initial path failure includes the steps of receiving one or more triggers at one of a destination node and a source node of a first path. The trigger indicates a path failure. The method continues by switching from the first path to a functional second path. The trigger prompts, at least partially, the switching step, and restores the circuit to a functional mode.
    Type: Grant
    Filed: May 8, 2001
    Date of Patent: March 14, 2006
    Assignee: Sycamore Networks, Inc.
    Inventors: Jack Zhu, Alok Kishore Bhargava, Ray Alexander Balogh
  • Patent number: 6961525
    Abstract: A method of channel balance for a channel balance section in an WDM optical network with a starting node, an ending node and a plurality of intermediate OADNs (Optical Add Drop Node) first determines express wavelengths and non-express wavelengths starting from the starting node, then calculates TX (transmitter) power change which will bring the express channel performance to a target value and sets TX power using obtained TX power value. The method then moves to non-express channels by calculating TX power change for each non-express channel and sets TX power using obtained TX power value. Lastly, for each intermediate OADN, the method calculates TX power change for each added channel in each OADN and sets TX power using obtained TX power value.
    Type: Grant
    Filed: October 23, 2001
    Date of Patent: November 1, 2005
    Assignee: Sycamore Networks, Inc.
    Inventor: Jinghui Li
  • Patent number: 6952405
    Abstract: A coding scheme is provided transporting encoded information over an optical communications link to a network. Multi-word information groups are analyzed to determine whether each of the information groups includes control characters. If the information group does not include any control characters, an encoded information stream including a set data indicator and data words is generated. If the information group includes one or more control characters, an encoded information stream is generated which includes control code counters, a transition indicator, location pointers, control codes that are encoded from the control characters, and any data. Accordingly, the necessary bandwidth for transporting the information is reduced by using this encoded information stream without sacrificing any control information.
    Type: Grant
    Filed: February 27, 2001
    Date of Patent: October 4, 2005
    Assignee: Sycamore Networks, Inc.
    Inventors: Danny Hin-Kwok Tsang, Murat Azizoglu
  • Patent number: 6912606
    Abstract: A serial bus is provided that supports multiple data transmission protocols. The serial bus allows a bus master to communicate with a variety of semiconductor devices that support a variety of serial interface standards. As a result, a single bus master may control and observe a JTAG-compatible semiconductor device, an SPI-compatible semiconductor device and an I2C compatible semiconductor device over the serial bus.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: June 28, 2005
    Assignee: Sycamore Networks, Inc.
    Inventor: Victor Fay
  • Patent number: 6862564
    Abstract: A system and a method for providing an emulated network including a plurality of emulated networking devices, in which a number of network node executable images are employed. Each of the network node executable images corresponds to one of the emulated networking devices. The emulated networking devices represent physical networking devices, such as optical switches. A portion of each of the network node executable images is operable to execute without modification on a physical networking device.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: March 1, 2005
    Assignee: Sycamore Networks, Inc.
    Inventors: Chikong Shue, John Thomas Moy, Tao Yang, Raymond Xie
  • Patent number: 6859468
    Abstract: The present invention discloses a vertical cavity surface emitting laser (VCSEL). The VCSEL comprises a first and second mirror stack. The VCSEL has an active region positioned between the first mirror stack and second mirror stack. Also, the VCSEL has a contact region in at least one of the active regions. The VCSEL encompasses a module for stabilizing the gains among a plurality of modes included by spatial power instability by increasing the current through the contact.
    Type: Grant
    Filed: May 29, 2001
    Date of Patent: February 22, 2005
    Assignee: Sycamore Networks, Inc.
    Inventor: Vijayanand Vusirikala
  • Patent number: 6839871
    Abstract: Indicia are provided to a client of Out-of-Frame errors and message bit parity errors that occur during the transmission of a message through a network, wherein the message includes the client data multiplexed with other data and formatted into a message that includes a plurality of transport overhead bytes. The transport overhead bytes of the multiplexed can include both defined bytes and undefined bytes. Predetermined bytes in the transport overhead may be used to store indicia of errors that are detected during the message transmission. These predetermined bytes are read by the client at the egress of the network. The transport overhead may contain both a section overhead portion and a line overhead portion and the predetermined bytes may be encoded in either a subset of the section or line overhead bytes. In addition, the indicia of errors may be encoded in an undefined portion of the section or line overhead.
    Type: Grant
    Filed: February 8, 2001
    Date of Patent: January 4, 2005
    Assignee: Sycamore Networks, Inc.
    Inventors: Naimish Patel, Richard A. Barry, Paolo Narvaez, Anthony Chi-Kong Kam
  • Patent number: 6839866
    Abstract: A method of providing reset logic in high availability computer systems is disclosed. The illustrative embodiment of the present invention uses probability theory in combination with redundant processors and components to ensure system availability. Detected errors are verified, and malfunctioning processors or components are then changed to a reset state that functionally removes them from the system. Detected errors which can not be verified result in the processor or component that incorrectly detected the error being placed in a reset state. The use of redundant components and processors enable standby processors to be activated to take the place of reset processors quickly enough to maintain system availability.
    Type: Grant
    Filed: May 31, 2001
    Date of Patent: January 4, 2005
    Assignee: Sycamore Networks, Inc.
    Inventor: Kenneth Lerman
  • Patent number: 6826372
    Abstract: An optical receiver circuit includes a differential limiter amplifier receiving a binary electrical waveform generated by an optical-to-electrical converter receiving an optical communications signal. Low-pass filter circuits are coupled to differential outputs of the limiter amplifier to obtain the average DC values of the mirror-image output signals. The outputs of the low-pass filter circuits are provided to a differential amplifier to obtain the difference between these average DC values. The output of the differential amplifier is provided to an integrator circuit whose slowly-varying output is provided to the limiter amplifier to establish a switching threshold for distinguishing logic “0”s from logic “1”s in the received data signal. The switching threshold is automatically adjusted in response to varying operation conditions such as changes in the received optical signal power.
    Type: Grant
    Filed: August 30, 2000
    Date of Patent: November 30, 2004
    Assignee: Sycamore Networks, Inc.
    Inventor: Mehrdad Givehchi
  • Patent number: 6823470
    Abstract: A system and method is provided for using a first data channel to pass working data and a second data channel to pass error correction information. For example, this second data channel may be defined along a redundant data path. For example, this error correction information may be forwarded error correction (FEC) information such as Hamming code information or any other type of error correction information. Use of the redundant path to forward FEC information provides several advantages: 1) the FEC information can be used to correct bit errors that occur within the system, making the system high-quality and more reliable and 2) use of the protected path provides an efficient method to constantly monitor the quality of both the working and redundant path. Monitoring is accomplished by using the FEC information on the redundant path in conjunction with the information on the working path to accurately count the number of errors that occur on the working and redundant paths.
    Type: Grant
    Filed: February 9, 2001
    Date of Patent: November 23, 2004
    Assignee: Sycamore Networks, Inc.
    Inventors: Douglas Edward Smith, Howard C. Reeve, III, James T. Francis, Jr.
  • Publication number: 20040208585
    Abstract: An optical transmission system with two counter propagating wavelength division multiplexed (WDM) optical signals carried by an optical fiber transmission line, has a first Raman pump for launching a first beam of pump energy for amplifying both WDM signals so that the first beam counter-propagates with respect to a first WDM signal The system also includes a second Raman pump for launching a second beam of pump energy for amplifying both WDM signals so that the second beam counter-propagates with respect to a second WDM signal.
    Type: Application
    Filed: March 20, 2002
    Publication date: October 21, 2004
    Applicant: Sycamore Networks, Inc.
    Inventor: Jinendra Kumar Ranka
  • Publication number: 20040208577
    Abstract: A method of adding wavelengths to an “in-service” WDM optical network system carrying live traffic. The method divides the wavelength into groups and adds each group of wavelengths into the working system in a parallel way by determining the desired TX launch power change for each wavelength from a predetermined value and applying the power changes for the group all together. When the system performance degradation happens after wavelengths addition, a wavelength power balance method according to another aspect of this invention can be applied to optimize the system performance. The power balance method first identifies the wavelengths to be optimized and classifies the wavelengths into controllable and reserved wavelengths; the total power available for wavelength adjustment is then determined; for each controllable wavelength, the required TX launch power which will bring the wavelength to meet the desired performance is determined and applied.
    Type: Application
    Filed: July 23, 2002
    Publication date: October 21, 2004
    Applicant: Sycamore Networks, Inc.
    Inventor: Michael John Laurence Cahill
  • Patent number: 6807001
    Abstract: A method and apparatus for detecting if an optical module has been disconnected from a fiber span or if there has been a break in the span, and for automatically reducing the output signal level of the optical module such that the output signal level is within an acceptable safety limit. Also disclosed is a system and technique for automatically resetting a Raman pump unit once the source of an optical leak has been located and addressed.
    Type: Grant
    Filed: April 9, 2002
    Date of Patent: October 19, 2004
    Assignee: Sycamore Networks, Inc.
    Inventors: Jinendra Kumar Ranka, Jeffrey David Christoph, Erie Anthony Kilpatrick
  • Patent number: 6754208
    Abstract: A method and apparatus are disclosed for spreading the component signals of a groomed input circuit through a three-stage CLOS switch network. The spreading algorithm includes sequentially evaluating each midstage switching module as to the availability of a connection between an assigned source switching module and an assigned destination switching module having sufficient spare bandwidth to accommodate one or more of the component signals. A load sharing algorithm can be used to spread the component signals among the midstage switching stages. In this way the available bandwidth of each of the midstage switching modules is evaluated for each of the component signals and each component signal is routed through the midstage switching module having the largest available bandwidth.
    Type: Grant
    Filed: August 1, 2001
    Date of Patent: June 22, 2004
    Assignee: Sycamore Networks, Inc.
    Inventors: Anthony Chi-Kong Kam, Naimish Patel
  • Patent number: 6741761
    Abstract: A method for improving the bit error rate of a modulated optical signal transmitted over single mode fiber is provided. The modulating voltage supplied to a single arm or alternatively to both arms of a Mach-Zehnder modulator is increased to result in a reduced extinction ratio of the modulated optical signal. This results in an optimum optical signal with a reduced bit error rate at a receiver coupled to the Mach-Zehnder modulator.
    Type: Grant
    Filed: June 28, 2001
    Date of Patent: May 25, 2004
    Assignee: Sycamore Networks, Inc.
    Inventor: Richard Sharp