公开(公告)号：US20220407736A1

公开(公告)日：2022-12-22

申请号：US17894673

申请日：2022-08-24

Applicant: Cisco Technology, Inc.

Inventor： Ijsbrand Wijnands ,  Pierre Pfister ,  Neale D.R Ranns ,  W. Mark Townsley ,  Gregory J. Shepherd

IPC: H04L12/18

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.

公开(公告)号：US11297117B2

公开(公告)日：2022-04-05

申请号：US16834551

申请日：2020-03-30

Applicant: Cisco Technology, Inc.

Inventor： Ijsbrand Wijnands ,  Thomas Kernen ,  Gregory J. Shepherd ,  Neale D. R. Ranns

IPC: H04L29/06 ,  H04L65/611 ,  H04L101/695 ,  H04L65/60 ,  H04L61/5069 ,  H04L61/103 ,  H04L61/5007

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.

公开(公告)号：US11044112B2

公开(公告)日：2021-06-22

申请号：US16525649

申请日：2019-07-30

Applicant: Cisco Technology, Inc.

Inventor： Ijsbrand Wijnands ,  Gregory J. Shepherd ,  John H. W. Bettink

IPC: H04L12/18 ,  H04L12/741 ,  H04L12/761

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.

公开(公告)号：US20200287733A1

公开(公告)日：2020-09-10

申请号：US16876217

申请日：2020-05-18

Applicant: Cisco Technology, Inc.

Inventor： Ijsbrand Wijnands ,  Gregory J. Shepherd ,  Christian J. Martin ,  Neale D. R. Ranns ,  Jesper Skriver

IPC: H04L12/18 ,  H04L12/761 ,  H04L12/741

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.

公开(公告)号：US20200228581A1

公开(公告)日：2020-07-16

申请号：US16834551

申请日：2020-03-30

Applicant: Cisco Technology, Inc.

Inventor： Ijsbrand Wijnands ,  Thomas Kernen ,  Gregory J. Shepherd ,  Neale D. R. Ranns

IPC: H04L29/06 ,  H04L29/12

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.

公开(公告)号：US10536324B2

公开(公告)日：2020-01-14

申请号：US15993050

申请日：2018-05-30

Applicant: Cisco Technology, Inc.

Inventor： Ijsbrand Wijnands ,  Gregory J. Shepherd ,  Christian J. Martin ,  Rajiv Asati

IPC: H04L12/18 ,  H04L12/24 ,  H04L12/761 ,  H04L12/707 ,  H04L12/703 ,  H04L12/741

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.

公开(公告)号：US10164794B2

公开(公告)日：2018-12-25

申请号：US15582090

申请日：2017-04-28

Applicant: Cisco Technology, Inc.

Inventor： Ijsbrand Wijnands ,  Neale D. R. Ranns ,  Gregory J. Shepherd ,  Nagendra Kumar Nainar

IPC: H04L12/18 ,  H04L12/46 ,  H04L12/723 ,  H04L12/741

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.

公开(公告)号：US20180069805A1

公开(公告)日：2018-03-08

申请号：US15797485

申请日：2017-10-30

Applicant: Cisco Technology, Inc.

Inventor： Neale D. R. Ranns ,  Ijsbrand Wijnands ,  Gregory J. Shepherd

IPC: H04L12/911 ,  H04L12/703

CPC classification number: H04L47/825 ,  H04L45/28

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.

公开(公告)号：US09853915B2

公开(公告)日：2017-12-26

申请号：US14932016

申请日：2015-11-04

Applicant: CISCO TECHNOLOGY, INC.

Inventor： Neale D. R. Ranns ,  Ijsbrand Wijnands ,  Gregory J. Shepherd

IPC: H04L1/22 ,  H04L12/911 ,  H04L12/703

CPC classification number: H04L47/825 ,  H04L45/28

Abstract: Various systems and methods for performing fast fail-over. For example, one method involves receiving a packet at a node. The packet is received at the node in response to a designated forwarder (DF) detecting loss of communication between the DF and a receiver node. The method also involves determining that the first packet was received via a tunnel. The method also involves forwarding the first packet and initiating a DF election. Forwarding the first packet and initiating the DF election are performed in response to determining that the first packet was received via the tunnel.

公开(公告)号：US09781029B2

公开(公告)日：2017-10-03

申请号：US15015463

申请日：2016-02-04

Applicant: Cisco Technology, Inc.

Inventor： Neale D. R. Ranns ,  Ijsbrand Wijnands ,  Gregory J. Shepherd

IPC: H04L12/28 ,  H04L12/705 ,  H04L12/18

CPC classification number: H04L45/18 ,  H04L12/1877 ,  H04L45/16

Abstract: Various systems and methods for preventing loops. For example, one method involves receiving a multicast data packet at a node. The node is coupled to a local area network (LAN). An internet protocol (IP) prefix is assigned to the LAN. The method involves determining whether a source address included in the packet is covered by the IP prefix. Depending on the direction of travel of the multicast data packet and whether or not the source address is covered by the IP prefix, the node determines whether a loop exists.