公开(公告)号：US10652135B2

公开(公告)日：2020-05-12

申请号：US15216007

申请日：2016-07-21

Applicant: Cisco Technology, Inc.

Inventor： Pascal Thubert ,  IJsbrand Wijnands ,  Patrick Wetterwald ,  Eric Levy-Abegnoli ,  Jean-Philippe Vasseur

IPC: H04L12/727 ,  H04L12/753 ,  H04L12/751 ,  H04L12/721 ,  H04L29/06 ,  H04L12/725

Abstract: In one embodiment, a multicast listener device floods a path lookup request to search for a multicast tree, and may then receive path lookup responses from candidate nodes on the multicast tree, where each of the path lookup responses indicates a unicast routing cost from a respective candidate node to the multicast listener device, and where each of the candidate nodes is configured to suppress a path lookup response if a total path latency from a source of the multicast tree to the multicast listener device via that respective candidate node is greater than a maximum allowable path latency. The multicast listener device may then select a particular candidate node as a join point for the multicast tree based on the particular node having a lowest associated unicast routing cost to the multicast listener device from among the candidate nodes, and joins the multicast tree at the selected join point.

公开(公告)号：US20220303046A1

公开(公告)日：2022-09-22

申请号：US17208293

申请日：2021-03-22

Applicant: Cisco Technology Inc.

Inventor： Mankamana Prasad Mishra ,  Nagendra Kumar Nainar ,  Carlos M. Pignataro ,  IJsbrand Wijnands

IPC: H04L1/00 ,  H04L12/741

Abstract: The present disclosure is directed to BIER forwarding over varying BSL domains, the methods including the steps of receiving, at a border node, a packet comprising a BIER header having a BIER bit string with a first bit string length; reading an incoming label of the packet comprising instructions to split the BIER header into a plurality of smaller headers associated with a plurality of smaller bit strings; generating a set of split bit masks; performing a separate bitwise AND operation on each split bit mask and the BIER bit string to generate the plurality of smaller bit strings, each copied to a corresponding smaller header of the plurality of smaller headers; and performing a lookup for each of the plurality of smaller headers on a respective forwarding table to determine one or more egress routers to which to transmit the packet.

公开(公告)号：US20220239585A1

公开(公告)日：2022-07-28

申请号：US17160508

申请日：2021-01-28

Applicant: Cisco Technology, Inc.

Inventor： Mankamana Prasad Mishra ,  Rajiv Asati ,  IJsbrand Wijnands ,  Stephane Litkowski ,  Nitin Kumar

IPC: H04L12/761 ,  H04L12/707 ,  H04L12/18 ,  H04L29/06 ,  H04L12/46

Abstract: A method is performed at a router configured to perform Bit Index Explicit Replication (BIER) for forwarding of multicast packets in a network. The method includes, upon receiving a multicast packet of a multicast flow, accessing flow mappings in which multicast flows are mapped to fixed accounting values corresponding to the multicast flows. The method further comprises generating a BIER header for the multicast packet by encoding a multi-segment entropy field of the BIER header with (i) a variable entropy value for equal-cost multi-path (ECMP) load balancing, and (ii) a fixed accounting value among the fixed accounting values that is mapped to the multicast flow in the flow mappings. The method also includes encapsulating the multicast packet with the BIER header to produce an encapsulated multicast packet, and forwarding the encapsulated multicast packet.

公开(公告)号：US11310154B2

公开(公告)日：2022-04-19

申请号：US16582906

申请日：2019-09-25

Applicant: Cisco Technology, Inc.

Inventor： IJsbrand Wijnands ,  Lukas Krattiger ,  Mankamana Prasad Mishra ,  Brian Christopher Farnham

IPC: H04L12/723 ,  H04L12/721 ,  H04L12/751 ,  H04L12/741 ,  H04L45/50 ,  H04L12/18 ,  G06F16/22 ,  H04L45/02 ,  H04L67/10

Abstract: In one embodiment, a first label-distribution-protocol (LDP) session is established between a first interface of a first computing device and a second computing device, while a second LDP session is established between a second interface and the second computing device. The method may further comprise receiving a request from a third computing device to subscribe to a multicast group, storing an association between a first label, the multicast group, and the first interface, and sending, to the second computing device via the first LDP session, an indication that the first label is associated with the multicast group. Further, the method may include receiving a request from a fourth computing device to subscribe to the multicast group, storing an association between a second label, the multicast group and, the second interface, and sending, via the second LDP session, an indication that the second label is associated with the multicast group.

公开(公告)号：US10855579B2

公开(公告)日：2020-12-01

申请号：US16268953

申请日：2019-02-06

Applicant: Cisco Technology, Inc.

Inventor： Mankamana Prasad Mishra ,  Pascal Thubert ,  IJsbrand Wijnands ,  Krishnaswamy Ananthamurthy ,  Ramakrishnan Chokkanathapuram Sundaram ,  Stig Ingvar Venaas

IPC: H04L12/28 ,  H04L12/721 ,  H04L12/761 ,  H04L12/749 ,  H04L12/755 ,  H04L12/753

Abstract: In one illustrative example, a network node connected in a network fabric may identify that it is established as part of a multicast distribution tree for forwarding multicast traffic from a source node to one or more host receiver devices of a multicast group. In response, the network node may propagate in the network fabric a message for advertising the network node as a candidate local source node at which to join the multicast group. The message for advertising may include data such as a reachability metric. The propagation of the message may be part of a flooding of such messages in the network fabric. The network node serving as the candidate local source node may thereafter “locally” join a host receiver device in the multicast group at the network node so that the device may receive the multicast traffic from the source node via the network node.

公开(公告)号：US10242740B2

公开(公告)日：2019-03-26

申请号：US14847019

申请日：2015-09-08

Applicant: Cisco Technology, Inc.

Inventor： IJsbrand Wijnands ,  Gregory J. Shepherd

IPC: G06F15/16 ,  G11C15/00 ,  H04L12/701

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.

公开(公告)号：US20240014923A1

公开(公告)日：2024-01-11

申请号：US18321854

申请日：2023-05-23

Applicant: Cisco Technology, Inc.

Inventor： Mankamana Prasad Mishra ,  Nagendra Kumar Nainar ,  Carlos M. Pignataro ,  IJsbrand Wijnands

IPC: H04L45/00 ,  H04L45/745

CPC classification number: H04L45/566 ,  H04L45/745

Abstract: The present disclosure is directed to BIER forwarding over varying BSL domains, the methods including the steps of receiving, at a border node, a packet comprising a BIER header having a BIER bit string with a first bit string length; reading an incoming label of the packet comprising instructions to split the BIER header into a plurality of smaller headers associated with a plurality of smaller bit strings; generating a set of split bit masks; performing a separate bitwise AND operation on each split bit mask and the BIER bit string to generate the plurality of smaller bit strings, each copied to a corresponding smaller header of the plurality of smaller headers; and performing a lookup for each of the plurality of smaller headers on a respective forwarding table to determine one or more egress routers to which to transmit the packet.

公开(公告)号：US11705983B2

公开(公告)日：2023-07-18

申请号：US17208293

申请日：2021-03-22

Applicant: Cisco Technology Inc.

Inventor： Mankamana Prasad Mishra ,  Nagendra Kumar Nainar ,  Carlos M. Pignataro ,  IJsbrand Wijnands

IPC: H04L45/745 ,  H04L1/00

CPC classification number: H04L1/0007 ,  H04L45/745

Abstract: The present disclosure is directed to BIER forwarding over varying BSL domains, the methods including the steps of receiving, at a border node, a packet comprising a BIER header having a BIER bit string with a first bit string length; reading an incoming label of the packet comprising instructions to split the BIER header into a plurality of smaller headers associated with a plurality of smaller bit strings; generating a set of split bit masks; performing a separate bitwise AND operation on each split bit mask and the BIER bit string to generate the plurality of smaller bit strings, each copied to a corresponding smaller header of the plurality of smaller headers; and performing a lookup for each of the plurality of smaller headers on a respective forwarding table to determine one or more egress routers to which to transmit the packet.

公开(公告)号：US11115329B1

公开(公告)日：2021-09-07

申请号：US16664582

申请日：2019-10-25

Applicant: Cisco Technology, Inc.

Inventor： Mankamana Prasad Mishra ,  IJsbrand Wijnands ,  Nagendra Kumar Nainar ,  Nitin Kumar

IPC: H04L12/721 ,  H04L12/741 ,  H04L12/723 ,  H04L12/761

Abstract: This disclosure describes a method usable in a network that has a combination of mLDP-capable and BIER-capable devices. The disclosed method includes advertising, by an mLDP-capable multicast source, an indication of a BIER edge router that it has determined is usable as a path between the BIER devices and the mLDP-capable multicast source. A provider edge router can include in a multicast join message both an indication of the mLDP-capable multicast source as well as the indication of the BIER router advertised as being usable as the path to the mLDP-capable multicast source. The BIER devices can communicate with each other to pass a multicast join message to the BIER edge router that is indicated as being usable as the path to the mLDP-capable multicast source.

公开(公告)号：US10270606B2

公开(公告)日：2019-04-23

申请号：US15863297

申请日：2018-01-05

Applicant: Cisco Technology, Inc.

Inventor： Pascal Thubert ,  IJsbrand Wijnands ,  Gregory Shepherd

IPC: H04L1/16 ,  H04L12/18 ,  H04L1/18 ,  H04W52/02 ,  H04W72/00 ,  H04L1/00 ,  H04W84/18

Abstract: In one embodiment, a device in a network sends a first multicast message to a plurality of destinations in the network. The first multicast message includes a first bitmap that identifies the destinations. The device receives one or more acknowledgements from a subset of the destinations. The device determines a retransmission bitmap that identifies those of the plurality of destinations that did not acknowledge the first multicast message, based on the received one or more acknowledgements. The device sends a retransmission multicast message to those of the plurality of destinations that did not acknowledge the first multicast message. The retransmission multicast message includes the retransmission bitmap.