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).

  • Publication number: 20200228360
    Abstract: Methods, network devices and computer readable media are disclosed relating to a communication network. In one embodiment, a method includes receiving a message comprising a message bit array. The message bit array identifies egress nodes for the message within a bit indexed explicit replication (BIER) domain of a communications network. A first bit position in the message bit array represents a first one or more of the egress nodes, and a bit value at the first bit position indicates that the message is to be forwarded to one of the first one or more of the egress nodes. The method further includes accessing a first forwarding table entry corresponding to the first bit position, determining whether the first bit position is an anycast bit position having multiple corresponding forwarding table entries, and forwarding the message to one of the first one or more of the egress nodes.
    Type: Application
    Filed: March 30, 2020
    Publication date: July 16, 2020
    Inventors: Ijsbrand Wijnands, Pierre Pfister, Neale D. R. Ranns, W. Mark Townsley, Gregory J. Shepherd
  • Publication number: 20200228581
    Abstract: Methods, network devices and computer readable media are disclosed for replication and switching of Internet Protocol (IP) packets in professional media networks. In one embodiment, a method includes receiving, at a first node in a network configured for bit indexed explicit replication (BIER), and via a replication fabric within the network, a packet comprising a packet bit array. Each receiver of a plurality of non-BIER-enabled receivers reachable via the replication fabric is represented by a relative bit position in the packet bit array, and a respective IP address is assigned to each receiver. The method further includes determining that an intended non-BIER-enabled receiver of the packet is a local receiver of the first node, obtaining the IP address assigned to the local receiver, removing the packet bit array from the packet and forwarding the packet, without the packet bit array, to the local receiver via unicast IP forwarding.
    Type: Application
    Filed: March 30, 2020
    Publication date: July 16, 2020
    Inventors: Ijsbrand Wijnands, Thomas Kernen, Gregory J. Shepherd, Neale D. R. Ranns
  • Patent number: 10708075
    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: March 13, 2018
    Date of Patent: July 7, 2020
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Nagendra Kumar Nainar, Christian Martin
  • Publication number: 20200169432
    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 next-hop upstream node configured for bit indexed forwarding, an incoming tree descriptor message comprising a tree identifier and a descriptor bit array. Bit values in the descriptor bit array identify intended destination nodes to be reached via a network tree identified by the tree identifier. The embodiment further includes replicating and modifying the incoming tree descriptor message to generate an outgoing tree descriptor message for a next-hop downstream node within the network tree. In addition, the embodiment includes sending the outgoing tree descriptor message to the next-hop downstream node and sending to the next-hop upstream node a local label allocated to the tree identifier.
    Type: Application
    Filed: January 31, 2020
    Publication date: May 28, 2020
    Inventors: Ijsbrand Wijnands, Neale D. R. Ranns, Gregory J. Shepherd, Nagendra Kumar Nainar
  • Patent number: 10659242
    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: July 31, 2018
    Date of Patent: May 19, 2020
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian J. Martin, Neale D. R. Ranns, Jesper Skriver
  • Patent number: 10637675
    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: Grant
    Filed: November 9, 2016
    Date of Patent: April 28, 2020
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Pierre Pfister, Neale D. R. Ranns, W. Mark Townsley, Gregory J. Shepherd
  • Patent number: 10630743
    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: Grant
    Filed: April 28, 2017
    Date of Patent: April 21, 2020
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Thomas Kernen, Gregory J. Shepherd, Neale D. R. Ranns
  • Publication number: 20200067722
    Abstract: Methods, devices and computer readable storage media for performing bit indexed explicit replication (BIER) are disclosed. One embodiment of a method includes obtaining, at an egress node of a network, a bit position assigned to the egress node. This embodiment also includes sending an outgoing advertisement to other nodes in the network, where the outgoing advertisement identifies the egress node and the assigned bit position. The bit position is within a bit mask comprising bits in a plurality of bit positions, and each bit position corresponds to a respective egress node of the network.
    Type: Application
    Filed: October 31, 2019
    Publication date: February 27, 2020
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian J. Martin
  • Patent number: 10574479
    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: September 13, 2018
    Date of Patent: February 25, 2020
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Neale D. R. Ranns, Gregory J. Shepherd, Nagendra Kumar Nainar
  • Publication number: 20200052918
    Abstract: Various systems and methods for performing bit indexed explicit replication (BIER). For example, one method involves receiving a membership message that was generated by an egress router, where the membership message comprises information identifying a multicast group, and information identifying a plurality of egress routers. The method identifies at least one bit position in the membership message that is associated with the first egress router, where at least one bit position of the plurality of bit positions is associated with the first egress router. The method also records membership of the first egress router in the multicast group, where the membership is recorded in a bit of a group membership table, and the bit corresponds to the bit position identified in the membership message.
    Type: Application
    Filed: October 16, 2019
    Publication date: February 13, 2020
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian J. Martin
  • Patent number: 10536324
    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: Grant
    Filed: May 30, 2018
    Date of Patent: January 14, 2020
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian J. Martin, Rajiv Asati
  • Patent number: 10498547
    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: Grant
    Filed: November 30, 2017
    Date of Patent: December 3, 2019
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian J. Martin
  • Publication number: 20190356500
    Abstract: Disclosed are systems and methods for generating a bit-indexed forwarding table (BIFT) that includes a plurality of entries, each of which corresponds to a bit position of a number of bit positions. Each such bit position represents an egress network node of a plurality of egress network nodes. The BIFT is generated from an existing BIFT that includes a number of existing BIFT entries. Further, the generating configures the BIFT to be used in forwarding a packet to one or more of the egress nodes, based at least in part on a bit string in the packet. In one embodiment, the generating includes selecting a bit position of the plurality of bit positions as a selected bit position, creating an entry of the plurality of entries, and converting an existing BIFT entry of the plurality of existing BIFT entries to the entry of the plurality of entries.
    Type: Application
    Filed: July 30, 2019
    Publication date: November 21, 2019
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, John H.W. Bettink
  • Patent number: 10484303
    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: Grant
    Filed: August 29, 2017
    Date of Patent: November 19, 2019
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Gregory J. Shepherd, Ijsbrand Wijnands, Neale Ranns, David Ward, Michael Francis O'Gorman
  • Patent number: 10461946
    Abstract: Various systems and methods for performing bit indexed explicit replication (BIER). For example, one method involves receiving a membership request at a node. The membership request is received from a host and the membership request identifies a multicast group. In response to receiving the membership request, the node generates a membership message. The membership message includes information identifying the multicast group and information identifying the node. The node transmits the membership to an overlay participant that stores a bit string associated with the multicast group.
    Type: Grant
    Filed: January 23, 2015
    Date of Patent: October 29, 2019
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Christian J. Martin
  • Publication number: 20190327168
    Abstract: Methods, network devices and computer readable media are disclosed for traffic-engineered forwarding through a new form of bit indexed explicit replication. In one embodiment, a method includes receiving, at an ingress node of a network, a message associated with a message flow, obtaining a message bit array corresponding to the message flow, encapsulating the message with the message bit array to form an encapsulated message, and forwarding the encapsulated message into the network. Bit positions in the message bit array are assigned to separate segments of a path or tree in the network, and an explicit path or tree for the message flow is defined as an end to end connection of multiple segments assigned bit positions having a first bit value in the message bit array.
    Type: Application
    Filed: June 28, 2019
    Publication date: October 24, 2019
    Inventors: Toerless Eckert, Ijsbrand Wijnands, Gregory J. Shepherd, Neale D. R. Ranns
  • Publication number: 20190280988
    Abstract: Various systems and methods for performing fast fail-over. One method involves electing a first node as a designated forwarder node and electing a second node as a backup designated forwarder node. Prior to detecting a loss of connectivity between the designated forwarder node and the local network, the method elects both the designated forwarder node and the backup designated forwarder node, and the designated forwarder node forwards to a core network at least a first packet received from a local network. Subsequent to detecting a loss of connectivity, using the backup designated forwarder node to forward an instance of a second packet to the core network. In one embodiment, the backup designated forwarder node forwards an instance of the second packet, via a tunnel, to the designated forwarder node, which then forwards the instance of the second packet to the core network following the loss of connectivity.
    Type: Application
    Filed: May 24, 2019
    Publication date: September 12, 2019
    Inventors: Neale D. R. Ranns, Ijsbrand Wijnands, Gregory J. Shepherd
  • Patent number: 10404482
    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. The node traverses the bit string and selects an entry in a bit indexed forwarding table (BIFT). The entry includes a forwarding bit mask. Based on the forwarding bit mask and the bit string, the node forwards the packet.
    Type: Grant
    Filed: July 24, 2017
    Date of Patent: September 3, 2019
    Assignee: Cisco Technology, Inc.
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, John H. W. Bettink
  • Publication number: 20190215176
    Abstract: Functionality for creating a bit routing table for use in a bit-indexed explicit replication (“BIER”) environment in disclosed herein. In one embodiment, this functionality includes receiving information from a host, and determining whether the information comprises a MAC address that is a bit-indexed explicit replication (“BIER”) MAC address. In response to determining that the information comprises a BIER MAC address, this functionality creates an entry corresponding to the MAC address in a bit routing table. This functionality also analyzes the information to determine a bit position that is associated with the host, and also determines a port via which the host is reachable. The functionality updates the bit routing table by storing information identifying the bit position and the port in the entry, such that the bit position and the port both correspond to the MAC address. This functionality can be used to route packets in a BIER environment.
    Type: Application
    Filed: December 31, 2018
    Publication date: July 11, 2019
    Inventors: Ijsbrand Wijnands, Gregory J. Shepherd, Nagendra Kumar Nainar
  • Patent number: 10341222
    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: September 23, 2015
    Date of Patent: July 2, 2019
    Assignee: Cisco Technology, Inc.
    Inventors: Toerless Eckert, Ijsbrand Wijnands, Gregory J. Shepherd, Neale D. R. Ranns