Patents by Inventor Michel Levy

Michel Levy 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: 11838198
    Abstract: In one embodiment, a method comprises identifying, by a path computation element, essential parent devices from a nonstoring destination oriented directed acyclic graph (DODAG) topology as dominating set members belonging to a dominating set; receiving, by the path computation element, an advertisement message specifying a first dominating set member having reachability to a second dominating set member, the reachability distinct from the nonstoring DODAG topology; and generating, by the path computation element based on the advertisement message, an optimized path for reaching a destination network device in the nonstoring DODAG topology via a selected sequence of dominating set members, the optimized path providing cut-through optimization across the nonstoring DODAG topology.
    Type: Grant
    Filed: July 2, 2020
    Date of Patent: December 5, 2023
    Assignee: Cisco Technology, Inc.
    Inventors: Pascal Thubert, Patrick Wetterwald, Jean-Philippe Vasseur, Eric Michel Levy-Abegnoli
  • Patent number: 11751156
    Abstract: In one embodiment, a method comprises: receiving, by a constrained wireless network device comprising a local clock, a plurality of messages from respective neighboring wireless network devices advertising as available parent devices in a directed acyclic graph of a time-synchronized network that is synchronized to a master clock device; determining, by the constrained wireless network device, a corresponding timing error of the local clock relative to each message output by the corresponding available parent device; and executing, by the constrained wireless network device, a distributed time synchronization of the local clock with the master clock device based on correlating the respective timing errors relative to the local clock.
    Type: Grant
    Filed: July 7, 2021
    Date of Patent: September 5, 2023
    Assignee: Cisco Technology, Inc.
    Inventors: Pascal Thubert, Patrick Wetterwald, Jean-Philippe Vasseur, Eric Michel Levy-Abegnoli
  • Patent number: 11751146
    Abstract: In one embodiment, a method comprises: determining, by a constrained network device in a low power and lossy network (LLN), a self-estimated density value of neighboring LLN devices based on wirelessly receiving an identified number of beacon message transmissions within an identified time interval from neighboring transmitting LLN devices in the LLN; setting, by the constrained network device, a first wireless transmit power value based on the self-estimated density value; and transmitting a beacon message at the first wireless transmit power value, the beacon message specifying the self-estimated density value, a corresponding trust metric for the self-estimated density value, and the first wireless transmit power value used by the constrained network device for transmitting the beacon message.
    Type: Grant
    Filed: June 2, 2022
    Date of Patent: September 5, 2023
    Assignee: Cisco Technology, Inc.
    Inventors: Pascal Thubert, Robert Edgar Barton, Jerome Henry, Eric Michel Levy-Abegnoli
  • Patent number: 11659436
    Abstract: In one embodiment, a method comprises: determining, by a network switching device, whether the network switching device is configured as one of multiple leaf network switching devices, one of multiple Top-of-Fabric (ToF) switching devices, or one of multiple intermediate switching devices in a switched data network having a leaf-spine switching architecture; if configured as a leaf switching device, limiting flooding of an advertisement only to a subset of the intermediate switching devices in response to detecting a mobile destination is reachable; if configured as an intermediate switching device, flooding the advertisement, received from any one of the leaf network switching devices, to connected ToF switching devices without installing any routing information specified within the advertisement; if configured as a ToF switching device, installing from the flooded advertisement the routing information and tunneling a data packet, destined for the mobile destination, to the leaf switching device having trans
    Type: Grant
    Filed: June 15, 2021
    Date of Patent: May 23, 2023
    Assignee: Cisco Technology, Inc.
    Inventors: Pascal Thubert, Patrick Wetterwald, Eric Michel Levy-Abegnoli
  • Patent number: 11558194
    Abstract: In one embodiment, a method comprises: receiving, by a parent network device providing at least a portion of a directed acyclic graph (DAG) according to a prescribed routing protocol in a low power and lossy network, a destination advertisement object (DAO) message, the DAO message specifying a target Internet Protocol (IP) address claimed by an advertising network device in the DAG and the DAO message further specifying a secure token associated with the target IP address; and selectively issuing a cryptographic challenge to the DAO message to validate whether the advertising network device generated the secure token.
    Type: Grant
    Filed: June 1, 2021
    Date of Patent: January 17, 2023
    Assignee: Cisco Technology, Inc.
    Inventors: Pascal Thubert, Huimin She, Patrick Wetterwald, Akram Ismail Sheriff, Eric Michel Levy-Abegnoli
  • Publication number: 20220295423
    Abstract: In one embodiment, a method comprises: determining, by a constrained network device in a low power and lossy network (LLN), a self-estimated density value of neighboring LLN devices based on wirelessly receiving an identified number of beacon message transmissions within an identified time interval from neighboring transmitting LLN devices in the LLN; setting, by the constrained network device, a first wireless transmit power value based on the self-estimated density value; and transmitting a beacon message at the first wireless transmit power value, the beacon message specifying the self-estimated density value, a corresponding trust metric for the self-estimated density value, and the first wireless transmit power value used by the constrained network device for transmitting the beacon message.
    Type: Application
    Filed: June 2, 2022
    Publication date: September 15, 2022
    Inventors: Pascal Thubert, Robert Edgar Barton, Jerome Henry, Eric Michel Levy-Abegnoli
  • Patent number: 11445454
    Abstract: In one embodiment, a method comprises: determining, by a constrained network device in a low power and lossy network (LLN), a self-estimated density value of neighboring LLN devices based on wirelessly receiving an identified number of beacon message transmissions within an identified time interval from neighboring transmitting LLN devices in the LLN; setting, by the constrained network device, a first wireless transmit power value based on the self-estimated density value; and transmitting a beacon message at the first wireless transmit power value, the beacon message specifying the self-estimated density value, a corresponding trust metric for the self-estimated density value, and the first wireless transmit power value used by the constrained network device for transmitting the beacon message.
    Type: Grant
    Filed: May 19, 2021
    Date of Patent: September 13, 2022
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Pascal Thubert, Robert Edgar Barton, Jerome Henry, Eric Michel Levy-Abegnoli
  • Patent number: 11362837
    Abstract: In one embodiment, a method comprises: identifying, by a root network device of a directed acyclic graph (DAG) in a low power and lossy network, a child network device in the DAG, including identifying a first rank associated with the child network device; allocating, by the root network device, an allocated rank for the child network device, the allocated rank different from the first rank; and outputting, by the root network device, a message to the child network device specifying the allocated rank, the message causing the child network device to implement the allocated rank in the DAG, including causing the child network device to generate and output a Destination Oriented Directed Acyclic Graph (DODAG) information object (DIO) message specifying the child network device is using the allocated rank.
    Type: Grant
    Filed: November 15, 2019
    Date of Patent: June 14, 2022
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Pascal Thubert, Huimin She, Patrick Wetterwald, Akram Ismail Sheriff, Eric Michel Levy-Abegnoli
  • Patent number: 11362957
    Abstract: In one embodiment, a method comprises receiving, by a transport layer executed by a processor circuit in an apparatus, an identifiable grouping of data; storing, by the transport layer, the data as transport layer packets in a buffer circuit in the apparatus, the storing including inserting into each transport layer packet a grouping identifier that identifies the transport layer packets as belonging to the identifiable grouping; and causing, by the transport layer, a plurality of transmitting deterministic network interface circuits to deterministically retrieve the transport layer packets from the buffer circuit for deterministic transmission across respective deterministic links, the grouping identifier enabling receiving deterministic network interface circuits to group the received transport layer packets, regardless of deterministic link, into a single processing group for a next receiving transport layer.
    Type: Grant
    Filed: August 20, 2020
    Date of Patent: June 14, 2022
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Pascal Thubert, Patrick Wetterwald, Eric Michel Levy-Abegnoli, Jean-Philippe Vasseur
  • Patent number: 11356961
    Abstract: In one embodiment, a method comprises: determining, by a constrained network device in a low power and lossy network (LLN), a self-estimated density value of neighboring LLN devices based on wirelessly receiving an identified number of beacon message transmissions within an identified time interval from neighboring transmitting LLN devices in the LLN; setting, by the constrained network device, a first wireless transmit power value based on the self-estimated density value; and transmitting a beacon message at the first wireless transmit power value, the beacon message specifying the self-estimated density value, a corresponding trust metric for the self-estimated density value, and the first wireless transmit power value used by the constrained network device for transmitting the beacon message.
    Type: Grant
    Filed: May 19, 2021
    Date of Patent: June 7, 2022
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Pascal Thubert, Robert Edgar Barton, Jerome Henry, Eric Michel Levy-Abegnoli
  • Patent number: 11310017
    Abstract: In one embodiment, a method comprises: identifying, by a receiving network device, a deterministic schedule comprising allocated time slots, each allocated time slot allocated for the receiving network device receiving a data packet from one of a plurality of transmitting network devices in a wireless deterministic data network; and selectively transmitting, by the receiving network device, an expectation message at initiation of each of the allocated time slots, each expectation message preempting transmission by any other network device during the corresponding allocated time slot, each expectation message generated by the receiving network device and identifying a corresponding transmitting network device that is expected to deterministically transmit a corresponding expected data packet to the receiving network device during the corresponding allocated time slot; the expectation message causing the corresponding identified transmitting network device to transmit the corresponding expected data packet duri
    Type: Grant
    Filed: January 20, 2020
    Date of Patent: April 19, 2022
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Pascal Thubert, Eric Michel Levy-Abegnoli
  • Publication number: 20220109548
    Abstract: In one embodiment, an access point is configured with a plurality of resource units (RUs). Each RU is configured to use a frequency range that differs from frequency ranges used by the other RUs. The access point determines a pattern of recurring signal performance over time. For each RU of the plurality of RUs, the pattern indicates the recurring signal performance with respect to a station when the station is located in a given physical location. The access point allocates one or more of the RUs for communicating with the station. The pattern is used for avoiding allocation of any of the RUs for which the station is predicted to experience strong multipath fading or other destructive interference.
    Type: Application
    Filed: December 16, 2021
    Publication date: April 7, 2022
    Inventors: Pascal Thubert, Jerome Henry, Patrick Michel Pierre Wetterwald, Eric Michel Levy-Abegnoli
  • Patent number: 11290302
    Abstract: In one embodiment, a method comprises causing, by an apparatus, establishment of first and second multicast trees within one or more underlay switching fabrics of one or more fat tree topologies, the first and second multicast trees comprising first and second multicast roots for multicast transmission to leaf network devices in the respective first and second multicast trees; causing, by the apparatus, establishment of an overlay tunnel between the first and second multicast roots, the overlay tunnel independent and distinct from the first and second multicast trees; causing the first multicast root to multicast transmit, via the first multicast tree, a data packet having been transmitted to the first multicast root; and causing the first multicast root to unicast transmit the data packet to the second multicast root via the overlay tunnel, for multicast transmission of the data packet by the second multicast root via the second multicast tree.
    Type: Grant
    Filed: January 20, 2020
    Date of Patent: March 29, 2022
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Pascal Thubert, Patrick Wetterwald, Eric Michel Levy-Abegnoli
  • Patent number: 11271774
    Abstract: In one embodiment, a method comprises identifying a fat tree network topology comprising top-of-fabric (ToF) switching devices, an intermediate layer of intermediate switching devices connected to each of the ToF switching devices, and a layer of leaf network devices; and causing a first leaf network device to initiate establishment of first and second redundant multicast trees for multicasting of data packets, including: causing first and second ToF switching devices to operate as roots of the first and second multicast trees according to first and second attribute types, respectively, causing the first leaf network device to select first and second of the intermediate switching devices as first and second flooding relays belonging to the first and second attribute types, respectively, and causing the first and second flooding relays to limit propagation of registration messages generated by the first leaf network device to the first and second ToF switching devices, respectively.
    Type: Grant
    Filed: January 20, 2020
    Date of Patent: March 8, 2022
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Pascal Thubert, Patrick Wetterwald, Eric Michel Levy-Abegnoli
  • Patent number: 11218284
    Abstract: In one embodiment, an access point is configured with a plurality of resource units (RUs). Each RU is configured to use a frequency range that differs from frequency ranges used by the other RUs. The access point receives first information indicating, for each RU, a first signal quality that the station associates with the respective RU. The access point receives second information indicating, for each RU, a second signal quality that the station associates with the respective RU. The access point further determines, based on at least the first information and the second information, a pattern indicating a recurring signal quality that the station associates with each RU. The access point uses the pattern to allocate one of the RUs for communicating with the station.
    Type: Grant
    Filed: September 9, 2019
    Date of Patent: January 4, 2022
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Pascal Thubert, Jerome Henry, Patrick Michel Pierre Wetterwald, Eric Michel Levy-Abegnoli
  • Patent number: 11212279
    Abstract: In one embodiment, a method comprises determining, by a link layer switch within a distributed link layer switched data network, a trust metric for a media access control (MAC) address used by a network device on a link layer connection provided by the link layer switch; receiving, by the link layer switch, a query originated by a second link layer switch in the distributed link layer switched data network, the query specifying the MAC address and a corresponding specified trust metric; and responding to the query, by the link layer switch, based on determining whether the specified trust metric indicates a higher trust level than the corresponding trust metric for the MAC address used by the network device on the link layer connection.
    Type: Grant
    Filed: February 4, 2019
    Date of Patent: December 28, 2021
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Eric Michel Levy-Abegnoli, Pascal Thubert, Patrick Wetterwald, Jean-Philippe Vasseur
  • Patent number: 11196588
    Abstract: A method includes identifying within a network topology, by an apparatus, a plurality of network devices; and establishing by the apparatus, a multiple tree topology comprising a first multicast tree and a second multicast tree, the first and second multicast trees operable as redundant trees for multicast traffic in the network topology, the establishing including: allocating a first of the network devices as a corresponding root of the first multicast tree, allocating a first group of intermediate devices from the network devices as first forwarding devices in the first multicast tree, allocating a second group of intermediate devices as belonging to first leaf devices in the first multicast tree, and allocating terminal devices of the network devices as belonging to the first leaf devices, and allocating a second of the network devices as the corresponding root of the second multicast tree, allocating the second group of intermediate devices as second forwarding devices in the second multicast tree, alloca
    Type: Grant
    Filed: September 27, 2019
    Date of Patent: December 7, 2021
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Pascal Thubert, Ramakrishnan Chokkanathapuram Sundaram, Patrick Wetterwald, Eric Michel Levy-Abegnoli
  • Publication number: 20210337493
    Abstract: In one embodiment, a method comprises: receiving, by a constrained wireless network device comprising a local clock, a plurality of messages from respective neighboring wireless network devices advertising as available parent devices in a directed acyclic graph of a time-synchronized network that is synchronized to a master clock device; determining, by the constrained wireless network device, a corresponding timing error of the local clock relative to each message output by the corresponding available parent device; and executing, by the constrained wireless network device, a distributed time synchronization of the local clock with the master clock device based on correlating the respective timing errors relative to the local clock.
    Type: Application
    Filed: July 7, 2021
    Publication date: October 28, 2021
    Inventors: PASCAL THUBERT, PATRICK WETTERWALD, JEAN-PHILIPPE VASSEUR, ERIC MICHEL LEVY-ABEGNOLI
  • Publication number: 20210306908
    Abstract: In one embodiment, a method comprises: determining, by a network switching device, whether the network switching device is configured as one of multiple leaf network switching devices, one of multiple Top-of-Fabric (ToF) switching devices, or one of multiple intermediate switching devices in a switched data network having a leaf-spine switching architecture; if configured as a leaf switching device, limiting flooding of an advertisement only to a subset of the intermediate switching devices in response to detecting a mobile destination is reachable; if configured as an intermediate switching device, flooding the advertisement, received from any one of the leaf network switching devices, to connected ToF switching devices without installing any routing information specified within the advertisement; if configured as a ToF switching device, installing from the flooded advertisement the routing information and tunneling a data packet, destined for the mobile destination, to the leaf switching device having trans
    Type: Application
    Filed: June 15, 2021
    Publication date: September 30, 2021
    Inventors: PASCAL THUBERT, PATRICK WETTERWALD, ERIC MICHEL LEVY-ABEGNOLI
  • Publication number: 20210288803
    Abstract: In one embodiment, a method comprises: receiving, by a parent network device providing at least a portion of a directed acyclic graph (DAG) according to a prescribed routing protocol in a low power and lossy network, a destination advertisement object (DAO) message, the DAO message specifying a target Internet Protocol (IP) address claimed by an advertising network device in the DAG and the DAO message further specifying a secure token associated with the target IP address; and selectively issuing a cryptographic challenge to the DAO message to validate whether the advertising network device generated the secure token.
    Type: Application
    Filed: June 1, 2021
    Publication date: September 16, 2021
    Inventors: PASCAL THUBERT, HUIMIN SHE, PATRICK WETTERWALD, AKRAM ISMAIL SHERIFF, ERIC MICHEL LEVY-ABEGNOLI