Patents by Inventor Gregory J Shepherd

Gregory J Shepherd 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: 10341221
    Abstract: Methods and network devices are disclosed for traffic-engineered forwarding through a new form of bit indexed explicit replication. In one embodiment, a method includes receiving at a first node in a network a message comprising a message bit array, and comparing bit values at one or more bit positions in the message bit array to one or more entries in a forwarding table stored at the first node. The one or more bit positions correspond in this embodiment to links in the network. This embodiment of the method further includes forwarding the message over a link represented in the forwarding table if a result of the comparing indicates that the link is included in a path to be taken by the message. In a further embodiment of the method, the message is a multicast message and forwarding the message comprises forwarding a replica of the multicast message.
    Type: Grant
    Filed: July 31, 2015
    Date of Patent: July 2, 2019
    Assignee: Cisco Technology, Inc.
    Inventors: Toerless Eckert, Ijsbrand Wijnands, Gregory J. Shepherd, Neale D. R. Ranns
  • Patent number: 10305818
    Abstract: Various systems and methods for performing fast fail-over. For example, one method involves electing a first node as a designated forwarder node and electing a second node as a backup designated forwarder node, where the designated forwarder node is used to forward at least a first packet to a downstream node. The method further involves detecting a loss of connectivity between the designated forwarder node and a downstream receiver node, where the designated forwarder node and the backup designated forwarder node are both elected prior to the loss of connectivity occurring. Moreover, subsequent to detecting the loss of connectivity, the method uses the backup designated forwarder node to forward at least a second packet to the downstream receiver node.
    Type: Grant
    Filed: October 30, 2017
    Date of Patent: May 28, 2019
    Assignee: Cisco Technology, Inc.
    Inventors: Neale D. R. Ranns, Ijsbrand Wijnands, Gregory J. Shepherd
  • Patent number: 10242740
    Abstract: In one embodiment of a system, apparatus, and method the system, apparatus, and method including a table of neighboring network nodes stored in a ternary content-addressable memory (T-CAM), each one of the neighboring network nodes being indexed as a Bit Index Explicit Replication (BIER) bitmap, a plurality of selector lines in the T-CAM, each selector line associated with one neighboring network node, a bit set in the T-CAM for one single selector line among the plurality of selector lines such that the set bit is associated with a single match line, the single match line to be set high when an input on the selector line matches the set bit and otherwise to be set low, and a plurality of bits set to do not care for other selector lines, beside the one single selector line, associated with the single match line. Related systems, apparatuses, and methods are also described.
    Type: Grant
    Filed: September 8, 2015
    Date of Patent: March 26, 2019
    Assignee: Cisco Technology, Inc.
    Inventors: IJsbrand Wijnands, Gregory J. Shepherd
  • Patent number: 10225090
    Abstract: Various systems and methods for performing bit indexed explicit replication (BIER) using multiprotocol label switching (MPLS). For example, one method involves receiving a packet that includes a MPLS label. The packet also includes a multicast forwarding entry. The method also involves determining, based on the value of the MPLS label, whether to use the multicast forwarding entry to forward the packet. The method further includes forwarding the packet.
    Type: Grant
    Filed: September 17, 2014
    Date of Patent: March 5, 2019
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian Martin, Neale D. R. Ranns, Jesper Skriver
  • Publication number: 20190068524
    Abstract: In one embodiment, a method includes receiving from a host node comprising a tenant multicast application with a single tenant deployment, an encapsulated multicast packet over unicast at a virtual replicator, the encapsulated multicast packet comprising receiver information for the virtual replicator, replicating the encapsulated multicast packet at the virtual replicator, and transmitting the encapsulated multicast packet over unicast to a plurality of receiving nodes based on the receiver information. The receiving nodes comprise the tenant multicast application and the virtual replicator operates in a cloud without multicast capability. An apparatus is also disclosed herein.
    Type: Application
    Filed: August 29, 2017
    Publication date: February 28, 2019
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Gregory J. Shepherd, Ijsbrand Wijnands, Neale Ranns, David Ward, Michael Francis O'Gorman
  • Patent number: 10218524
    Abstract: Various systems and methods for performing bit indexed explicit replication (BIER). For example, one method involves receiving a link layer protocol frame at a network device. The link layer protocol frame includes a MAC address that identifies the link layer protocol frame as a being a multicast frame. The method then involves selecting a subset of ports included on the network device and forwarding the link layer protocol frame to only the selected subset of ports.
    Type: Grant
    Filed: November 7, 2014
    Date of Patent: February 26, 2019
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Nagendra Kumar Nainar
  • Publication number: 20190058606
    Abstract: Various systems and methods for performing bit indexed explicit replication (BIER) using multiprotocol label switching (MPLS). For example, one method involves receiving a packet that includes a MPLS label. The packet also includes a multicast forwarding entry. The method also involves determining, based on the value of the MPLS label, whether to use the multicast forwarding entry to forward the packet. The method further includes forwarding the packet.
    Type: Application
    Filed: July 31, 2018
    Publication date: February 21, 2019
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian J. Martin, Neale D. R. Ranns, Jesper Skriver
  • Publication number: 20190013964
    Abstract: Methods and network devices are disclosed for traversal, within a network configured for bit indexed forwarding, of a subnetwork having nodes not configured for bit indexed forwarding. In one embodiment, a method includes receiving, from a first network node not configured for bit indexed forwarding, a data message comprising a local label and a message bit array. Bit values in the message bit array identify intended destination nodes for the message. The embodiment further includes modifying the message bit array to exclude as intended destination nodes for the message any nodes not represented by one or more relative bit positions associated with the local label and stored in an ingress filter data structure. In addition, the embodiment includes forwarding a copy of the data message to a second network node, which is configured for bit indexed forwarding, identified in an accessed entry of a bit indexed forwarding table.
    Type: Application
    Filed: September 13, 2018
    Publication date: January 10, 2019
    Inventors: Ijsbrand Wijnands, Neale D. R. Ranns, Gregory J. Shepherd, Nagendra Kumar Nainar
  • Patent number: 10164794
    Abstract: Methods and network devices are disclosed for traversal, within a network configured for bit indexed forwarding, of a subnetwork having nodes not configured for bit indexed forwarding. In one embodiment, a method includes receiving, from a first network node not configured for bit indexed forwarding, a data message comprising a local label and a message bit array. Bit values in the message bit array identify intended destination nodes for the message. The embodiment further includes modifying the message bit array to exclude as intended destination nodes for the message any nodes not represented by one or more relative bit positions associated with the local label and stored in an ingress filter data structure. In addition, the embodiment includes forwarding a copy of the data message to a second network node, which is configured for bit indexed forwarding, identified in an accessed entry of a bit indexed forwarding table.
    Type: Grant
    Filed: April 28, 2017
    Date of Patent: December 25, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Neale D. R. Ranns, Gregory J. Shepherd, Nagendra Kumar Nainar
  • Publication number: 20180316520
    Abstract: Methods and network devices are disclosed for traversal, within a network configured for bit indexed forwarding, of a subnetwork having nodes not configured for bit indexed forwarding. In one embodiment, a method includes receiving, from a first network node not configured for bit indexed forwarding, a data message comprising a local label and a message bit array. Bit values in the message bit array identify intended destination nodes for the message. The embodiment further includes modifying the message bit array to exclude as intended destination nodes for the message any nodes not represented by one or more relative bit positions associated with the local label and stored in an ingress filter data structure. In addition, the embodiment includes forwarding a copy of the data message to a second network node, which is configured for bit indexed forwarding, identified in an accessed entry of a bit indexed forwarding table.
    Type: Application
    Filed: April 28, 2017
    Publication date: November 1, 2018
    Inventors: Ijsbrand Wijnands, Neale D. R. Ranns, Gregory J. Shepherd, Nagendra Kumar Nainar
  • Publication number: 20180278470
    Abstract: Methods, devices and program instructions are disclosed for performing bit indexed explicit replication (BIER) including fast reroute capability. One embodiment of a method includes receiving, from an egress node of a BIER network, an advertisement at a forwarding node, where the advertisement identifies a mapping of the egress node to a bit position of a packet bit string to be carried by a packet through the network. The embodiment further includes generating or updating a primary entry for the egress node in a bit indexed routing table (BIRT) for the forwarding node, and determining whether a backup entry for the egress node is to be included in the BIRT. In response to a determination that a backup entry is to be included, the embodiment further includes generating or updating the backup entry in the BIRT.
    Type: Application
    Filed: May 30, 2018
    Publication date: September 27, 2018
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian J. Martin, Rajiv Asati
  • Patent number: 10033632
    Abstract: A method and network device are disclosed for multicast forwarding. In one embodiment, the method includes receiving at a node configured to use a bit-indexed forwarding table a multicast message comprising an incoming message bit array. The method further includes comparing the incoming message bit array to a first neighbor bit array within a first forwarding table entry, and determining that for at least one relative bit position in the bit arrays a corresponding destination node is both a destination for the message and a reachable destination from a first neighboring node. The method further includes forwarding toward the first neighboring node a copy of the message, where a first node on the path of the forwarded message is not configured to use a respective bit-indexed forwarding table. An embodiment of the device includes a network interface, a memory and a processor configured to perform steps of the method.
    Type: Grant
    Filed: January 9, 2017
    Date of Patent: July 24, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian Martin
  • Publication number: 20180205565
    Abstract: Various systems and methods for performing bit indexed explicit replication (BIER) using IPv6. For example, one method involves receiving, at a node, a packet that includes an IP header. The packet also includes a multicast forwarding entry. The method also involves comparing the multicast forwarding entry with forwarding information stored by the node and selecting a neighbor based on the comparing. The method further includes forwarding the packet to the neighbor.
    Type: Application
    Filed: March 13, 2018
    Publication date: July 19, 2018
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Nagendra Kumar Nainar, Christian Martin
  • Patent number: 10003494
    Abstract: Various systems and methods for performing bit indexed explicit replication (BIER). For example, one method involves receiving a packet at a node. The packet includes a bit string includes information identifying a plurality of destinations. The node selects an entry in a bit indexed forwarding table (BIFT). The BIFT includes both a primary path entry and a backup path entry. The node forwards the packet based on information in the entry.
    Type: Grant
    Filed: January 23, 2015
    Date of Patent: June 19, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian J. Martin, Rajiv Asati
  • Publication number: 20180131532
    Abstract: Methods and network devices are disclosed relating to a multi-area communication network employing bit indexed explicit replication (BIER). In one embodiment, a method includes receiving, at a node in a communications network, a message comprising a first message bit array. The method further includes detecting a bit value of a first relative bit position in the first message bit array, where the first relative bit position represents a first group of destination nodes in the communications network, and evaluating the bit value of the first relative bit position in order to determine whether to encapsulate the received message for delivery to the first group of destination nodes. An embodiment of a network device comprises a processor adapted to implement an embodiment of the method.
    Type: Application
    Filed: November 9, 2016
    Publication date: May 10, 2018
    Inventors: Ijsbrand Wijnands, Pierre Pfister, Neale D. R. Ranns, W. Mark Townsley, Gregory J. Shepherd
  • Patent number: 9948574
    Abstract: Methods and network devices are disclosed for multicast forwarding. In one embodiment, a method includes receiving at a node a multicast message comprising a message header, where the message header comprises an incoming message bit array and a set identifier value associated with the incoming message bit array. The method further comprises selecting a first forwarding table entry, the first forwarding table entry comprises a set identifier value matching that of the message header. The method further comprises comparing at least a portion of the incoming message bit array to a corresponding portion of a neighbor bit array of the first forwarding table entry, determining that for at least one relative bit position a corresponding destination node is both a destination for the message and a reachable destination from a first neighboring node, and forwarding a copy of the message to the first neighboring node.
    Type: Grant
    Filed: August 31, 2016
    Date of Patent: April 17, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Gregory J. Shepherd, Ijsbrand Wijnands, Christian Martin
  • Patent number: 9942053
    Abstract: Various systems and methods for performing bit indexed explicit replication (BIER) using IPv6. For example, one method involves receiving, at a node, a packet that includes an IP header. The packet also includes a multicast forwarding entry. The method also involves comparing the multicast forwarding entry with forwarding information stored by the node and selecting a neighbor based on the comparing. The method further includes forwarding the packet to the neighbor.
    Type: Grant
    Filed: September 17, 2014
    Date of Patent: April 10, 2018
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Nagendra Kumar Nainar, Christian Martin
  • Publication number: 20180091473
    Abstract: Methods and network devices are disclosed for replication and switching of Internet Protocol (IP) packets in professional media networks. In one embodiment, a method includes encapsulating a unicast IP packet with a packet bit array and forwarding the encapsulated packet via a replication fabric within a network. In this embodiment, each receiver of a plurality of receivers reachable via the replication fabric is represented by a relative bit position in the packet bit array, a respective IP address is assigned to each receiver of the plurality of receivers, and the replication fabric is adapted to store disposition information mapping a relative bit position representing one or more of the plurality of receivers to IP addresses assigned to the one or more of the plurality of receivers. An embodiment of a network device includes a processor operably coupled to a network interface and adapted to perform steps of the method.
    Type: Application
    Filed: April 28, 2017
    Publication date: March 29, 2018
    Inventors: Ijsbrand Wijnands, Thomas Kernen, Gregory J. Shepherd, Neale D. R. Ranns
  • Publication number: 20180083790
    Abstract: Methods, devices and computer readable storage media for performing bit indexed explicit replication (BIER) are disclosed. One embodiment of a method includes receiving, at an ingress node of a network, a data packet comprising a multicast group identifier. This embodiment also includes obtaining, from a group membership table, a bit mask corresponding to the multicast group identifier. The bit mask comprises a plurality of bit positions, and each bit position corresponds to a respective egress node of the network. The embodiment also includes encapsulating the data packet with the bit mask and forwarding the encapsulated data packet using the bit mask.
    Type: Application
    Filed: November 30, 2017
    Publication date: March 22, 2018
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian J. Martin
  • Publication number: 20180069805
    Abstract: Various systems and methods for performing fast fail-over. For example, one method involves electing a first node as a designated forwarder node and electing a second node as a backup designated forwarder node, where the designated forwarder node is used to forward at least a first packet to a downstream node. The method further involves detecting a loss of connectivity between the designated forwarder node and a downstream receiver node, where the designated forwarder node and the backup designated forwarder node are both elected prior to the loss of connectivity occurring. Moreover, subsequent to detecting the loss of connectivity, the method uses the backup designated forwarder node to forward at least a second packet to the downstream receiver node.
    Type: Application
    Filed: October 30, 2017
    Publication date: March 8, 2018
    Inventors: Neale D. R. Ranns, Ijsbrand Wijnands, Gregory J. Shepherd