Patents by Inventor Hari Shankar

Hari Shankar has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10103815
    Abstract: The present invention is directed to optical communication systems and methods thereof. In various embodiments, the present invention provides method for linearizing Mach Zehnder modulators by digital pre-compensation and adjusting the gain of the driver and/or the modulation index. The pre-compensation can be implemented as a digital pre-compensation algorithm, which is a part of an adaptive feedback loop. There are other embodiments as well.
    Type: Grant
    Filed: February 26, 2018
    Date of Patent: October 16, 2018
    Assignee: INPHI CORPORATION
    Inventor: Hari Shankar
  • Patent number: 10091170
    Abstract: In one embodiment, a method includes establishing at a security device, a secure session for transmitting data between a client device and an end host, receiving decrypted data at the security device from the client device, inspecting the decrypted data at the security device, encrypting the decrypted data at the security device, and transmitting encrypted data to the end host. Decryption at the client device is offloaded from the security device to distribute decryption and encryption processes between the client device and the security device. An apparatus and logic are also disclosed herein.
    Type: Grant
    Filed: March 31, 2016
    Date of Patent: October 2, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Hari Shankar, Jin Teng, Venkatesh Narsipur Gautam
  • Publication number: 20180205464
    Abstract: The present invention is directed to data communication system and methods. More specifically, various embodiments of the present invention provide a communication interface that is configured to transfer data at high bandwidth using PAM format(s) over optical communication networks. In various embodiments, amplitude and phase of the optical wave are modulated. There are other embodiments as well.
    Type: Application
    Filed: January 17, 2018
    Publication date: July 19, 2018
    Inventors: Tom Peter Edward BROEKAERT, Hari SHANKAR
  • Patent number: 10027627
    Abstract: A network security device (NSD) is connected between a network and an endpoint device configured to host a client application. The client application communicates with the network through the network security device using a request-response protocol. The NSD receives from the client application a request destined for the network and that seeks a response from the network. The request has a context header including context information about the client application. The NSD determines whether the client application or a file accessed thereby has a suspicious nature based on the context information. If it is determined that the client application or the file accessed thereby has a suspicious nature, the NSD blocks the request from the network, and sends to the client application a response indicating the block.
    Type: Grant
    Filed: October 7, 2015
    Date of Patent: July 17, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Vincent E. Parla, Hari Shankar, Constantinos Kleopa, Venkatesh N. Gautam, Gerald N. A. Selvam
  • Publication number: 20180198527
    Abstract: The present invention is directed to data communication system and methods. More specifically, various embodiments of the present invention provide a communication interface that is configured to transfer data at high bandwidth using PAM format(s) over optical communication networks. A feedback mechanism is provided for adjusting the transmission power levels. There are other embodiments as well.
    Type: Application
    Filed: March 9, 2018
    Publication date: July 12, 2018
    Inventors: Sudeep BHOJA, Chao XU, Hari SHANKAR
  • Publication number: 20180191443
    Abstract: The present invention is directed to optical communication systems and methods thereof. In various embodiments, the present invention provides method for linearizing Mach Zehnder modulators by digital pre-compensation and adjusting the gain of the driver and/or the modulation index. The pre-compensation can be implemented as a digital pre-compensation algorithm, which is a part of an adaptive feedback loop. There are other embodiments as well.
    Type: Application
    Filed: February 26, 2018
    Publication date: July 5, 2018
    Inventor: Hari SHANKAR
  • Patent number: 9948396
    Abstract: The present invention is directed to data communication system and methods. More specifically, various embodiments of the present invention provide a communication interface that is configured to transfer data at high bandwidth using PAM format(s) over optical communication networks. A feedback mechanism is provided for adjusting the transmission power levels. There are other embodiments as well.
    Type: Grant
    Filed: September 29, 2016
    Date of Patent: April 17, 2018
    Assignee: INPHI CORPORATION
    Inventors: Sudeep Bhoja, Chao Xu, Hari Shankar
  • Patent number: 9941970
    Abstract: The present invention is directed to optical communication systems and methods thereof. In various embodiments, the present invention provides method for linearizing Mach Zehnder modulators by digital pre-compensation and adjusting the gain of the driver and/or the modulation index. The pre-compensation can be implemented as a digital pre-compensation algorithm, which is a part of an adaptive feedback loop. There are other embodiments as well.
    Type: Grant
    Filed: July 29, 2016
    Date of Patent: April 10, 2018
    Assignee: INPHI CORPORATION
    Inventor: Hari Shankar
  • Patent number: 9912411
    Abstract: The present invention is directed to data communication system and methods. More specifically, various embodiments of the present invention provide a communication interface that is configured to transfer data at high bandwidth using PAM format(s) over optical communication networks. In various embodiments, amplitude and phase of the optical wave are modulated. There are other embodiments as well.
    Type: Grant
    Filed: September 27, 2016
    Date of Patent: March 6, 2018
    Assignee: INPHI CORPORATION
    Inventors: Tom Peter Edward Broekaert, Hari Shankar
  • Publication number: 20180062751
    Abstract: The present invention relates to telecommunication techniques and integrated circuit (IC) devices. More specifically, embodiments of the present invention provide an off-quadrature modulation system. Once an off-quadrature modulation position is determined, a ratio between DC power transfer amplitude and dither tone amplitude for a modulator is as a control loop target to stabilize off-quadrature modulation. DC power transfer amplitude is obtained by measuring and sampling the output of an optical modulator. Dither tone amplitude is obtained by measuring and sampling the modulator output and performing calculation using the optical modulator output values and corresponding dither tone values. There are other embodiments as well.
    Type: Application
    Filed: November 2, 2017
    Publication date: March 1, 2018
    Inventors: Todd ROPE, Radhakrishnan L. NAGARAJAN, Hari SHANKAR
  • Patent number: 9838134
    Abstract: The present invention relates to telecommunication techniques and integrated circuit (IC) devices. More specifically, embodiments of the present invention provide an off-quadrature modulation system. Once an off-quadrature modulation position is determined, a ratio between DC power transfer amplitude and dither tone amplitude for a modulator is as a control loop target to stabilize off-quadrature modulation. DC power transfer amplitude is obtained by measuring and sampling the output of an optical modulator. Dither tone amplitude is obtained by measuring and sampling the modulator output and performing calculation using the optical modulator output values and corresponding dither tone values. There are other embodiments as well.
    Type: Grant
    Filed: December 30, 2015
    Date of Patent: December 5, 2017
    Assignee: INPHI CORPORATION
    Inventors: Todd Rope, Radhakrishnan L. Nagarajan, Hari Shankar
  • Patent number: 9819412
    Abstract: The present invention is directed to communication systems and techniques thereof. More specifically, embodiments of the present invention provide a calibration system for optical transmitter. The calibration system provides a predetermined set of operating parameters to the optical transmitter and measures the second harmonic value of the transmitter output. A calibrated set of parameters is determined by selecting operating parameters associated with the minimum second harmonic value. There are other embodiments as well.
    Type: Grant
    Filed: May 4, 2016
    Date of Patent: November 14, 2017
    Assignee: INPHI CORPORATION
    Inventors: Hari Shankar, Ariel Nachum
  • Publication number: 20170289104
    Abstract: In one embodiment, a method includes establishing at a security device, a secure session for transmitting data between a client device and an end host, receiving decrypted data at the security device from the client device, inspecting the decrypted data at the security device, encrypting the decrypted data at the security device, and transmitting encrypted data to the end host. Decryption at the client device is offloaded from the security device to distribute decryption and encryption processes between the client device and the security device. An apparatus and logic are also disclosed herein.
    Type: Application
    Filed: March 31, 2016
    Publication date: October 5, 2017
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Hari Shankar, Jin Teng, Venkatesh Narsipur Gautam
  • Patent number: 9686081
    Abstract: A computer-implemented method is provided to detect a compromised Certificate Authority (CA). Over time reports are received containing data describing certificate authority certificates captured from messages exchanged between clients and servers. These reports may be received by a central computing entity. Metadata and statistics for certificates contained in the reports are stored. It is determined whether a certificate authority has been compromised based on the metadata and statistics.
    Type: Grant
    Filed: July 1, 2015
    Date of Patent: June 20, 2017
    Assignee: Cisco Technology, Inc.
    Inventors: Jianxin Wang, Hari Shankar
  • Patent number: 9680783
    Abstract: An email update system dynamically updates the content of an email when the originator of an email has sent the email, and the originator later determines that the email requires editing. The updating may take place transparent to the recipient and without the introduction of duplicative content into the recipient's email program. The email update system comprises a delta engine program and a delta temporary storage in a sender's computer, a queue manager program and an intermediate email queue in a server computer, and a recipient email retrieval program in a recipient's computer.
    Type: Grant
    Filed: October 10, 2014
    Date of Patent: June 13, 2017
    Assignee: SNAP INC.
    Inventors: Yen-Fu Chen, John W. Dunsmoir, Hari Shankar
  • Publication number: 20170104722
    Abstract: A network security device (NSD) is connected between a network and an endpoint device configured to host a client application. The client application communicates with the network through the network security device using a request-response protocol. The NSD receives from the client application a request destined for the network and that seeks a response from the network. The request has a context header including context information about the client application. The NSD determines whether the client application or a file accessed thereby has a suspicious nature based on the context information. If it is determined that the client application or the file accessed thereby has a suspicious nature, the NSD blocks the request from the network, and sends to the client application a response indicating the block.
    Type: Application
    Filed: October 7, 2015
    Publication date: April 13, 2017
    Inventors: Vincent E. Parla, Hari Shankar, Constantinos Kleopa, Venkatesh N. Gautam, Gerald N.A. Selvam
  • Patent number: 9619160
    Abstract: In one embodiment, a node coupled to a plurality of storage devices executes a storage input/output (I/O) stack having a plurality of layers including a persistence layer. A portion of non-volatile random access memory (NVRAM) is configured as one or more logs. The persistence layer cooperates with the NVRAM to employ the log to record write requests received from a host and to acknowledge successful receipt of the write requests to the host. The log has a set of entries, each entry including (i) write data of a write request and (ii) a previous offset referencing a previous entry of the log. After a power loss, the acknowledged write requests are recovered by replay of the log in reverse sequential order using the previous record offset in each entry to traverse the log.
    Type: Grant
    Filed: August 28, 2015
    Date of Patent: April 11, 2017
    Assignee: NetApp, Inc.
    Inventors: Kayuri H. Patel, Hari Shankar
  • Patent number: 9612457
    Abstract: An integrated optical modulator device. The device can include a driver module coupled to an optical modulator. The optical modulator is characterized by a raised cosine transfer function. This optical modulator can be coupled to a light source and a bias control module, which is configured to apply an off-quadrature bias to the optical modulator. This bias can be accomplished by applying an inverse of the modulator transfer function to the optical modulator in order to minimize a noise variance. This compression function can result in an optimized increased top eye opening for a signal associated with the optical modulator. Furthermore, the optical modulator can be coupled to an EDFA (Erbium Doped Fiber Amplifier) that is coupled to a filter coupled an O/E (Optical-to-Electrical) receiver.
    Type: Grant
    Filed: November 10, 2016
    Date of Patent: April 4, 2017
    Assignee: INPHI CORPORATION
    Inventors: Radhakrishnan L. Nagarajan, Hari Shankar, Masaki Kato, Yang Fu
  • Publication number: 20170059889
    Abstract: An integrated optical modulator device. The device can include a driver module coupled to an optical modulator. The optical modulator is characterized by a raised cosine transfer function. This optical modulator can be coupled to a light source and a bias control module, which is configured to apply an off-quadrature bias to the optical modulator. This bias can be accomplished by applying an inverse of the modulator transfer function to the optical modulator in order to minimize a noise variance. This compression function can result in an optimized increased top eye opening for a signal associated with the optical modulator. Furthermore, the optical modulator can be coupled to an EDFA (Erbium Doped Fiber Amplifier) that is coupled to a filter coupled an O/E (Optical-to-Electrical) receiver.
    Type: Application
    Filed: November 10, 2016
    Publication date: March 2, 2017
    Inventors: Radhakrishnan L. NAGARAJAN, Hari SHANKAR, Masaki KATO, Yang FU
  • Publication number: 20170019179
    Abstract: The present invention is directed to data communication system and methods. More specifically, various embodiments of the present invention provide a communication interface that is configured to transfer data at high bandwidth using PAM format(s) over optical communication networks. A feedback mechanism is provided for adjusting the transmission power levels. There are other embodiments as well.
    Type: Application
    Filed: September 29, 2016
    Publication date: January 19, 2017
    Inventors: Sudeep BHOJA, Chao XU, Hari SHANKAR