Cisco Technology, Inc.

Ciena Corporation

Muthurajah Sivabalan

Sami Boutros

David Delano Ward

Clarence Filsfils

Jean-Philippe Vasseur

George Swallow

Stefano Benedetto Previdi

Tao Wang

Tarek Saad

Zafar Ali

Rakesh Gandhi

Ashwath Narasimhan

Carlos M Pignataro

Stewart Frederick Bryant

Cengiz Alaettinoglu

Himanshu Shah

Rex Emmanuel Fernando

Luca Martini

Carol Etta Iturralde

Santiago Alvarez

Lakshmi Rajasekaran

Jerome Henry

Nagendra Kumar Nainar

Robert Edgar Barton

Jan Medved

Ian Michael Charles Shand

Francois Clad

John Galen Scudder

John H W Bettink

Reshad Rahman

Pradosh Mohapatra

David Gilson

Yuri Tsier

Lakshmi Sharma

Amal Karboubi

Peng He

Santiago Vazquez Freitas

Bruce McDougall

Rodolphe Figaro

Show Chung Chin

Robert Keith Fielding

Peter Psenak

Maik Guenter Seewald

Syed Kamran Raza

Robert Goguen

Daniel C Frost

Robert H Thomas

Nobushige Akiya

Anca Zamfir

Arun Prakash

Simon James Trevor Spraggs

Michael Alan Kowal

Pranav Mehta

Arjun Sreekantiah

Bertrand Duvivier

Sowmya Chandran

Divya Bhargava

Nagi Reddy Jonnala

Simon Spraggs

Arif Aboobacker

Jahanzeb Baqai

Wade Miller

Martin Pepin

Ram Parameswaran

Frédéric Perras

Ramesh Uppili

Jean Philippe Vasseur

Reshad A Rahman

Robert Thomas

A method implemented by a node in a network utilizing Multiprotocol Label Switching (MPLS) includes performing a convergence procedure to discover the topology of a network in which multiple nodes are arranged; and upon determining that the topology of the network is a ring topology whereby the node is connected to two neighboring nodes by a respective link, creating a first table for a first link, the first table including labels representing at least a portion of a label stack for allowing the node to transmit packets to another node in the network in a clockwise (CW) direction around the ring; and creating a second table for a second link, the second table including labels representing at least a portion of a label stack for allowing the node to transmit packets to another node in the network in an anti-clockwise (ACW) direction around the ring.

Label distribution protocol (LDP) convergence in ring topologies

A Provider Edge (PE) node is configured to provide a Layer 2 Virtual Private Local Area Network (LAN) service (VPLS) having a simplified control plane. The PE node includes circuitry configured to receive a packet from a second PE node in the network, wherein the packet includes (1) a Destination Media Access Control (MAC) address associated with a destination Customer Edge (CE) node, (2) a source MAC address associated with a source CE node, and (3) a Virtual Local Area Network (VLAN) Identifier used to represent one of the second PE node and a multihome configuration including the second PE node, and learn the source MAC address associated with the source CE node as being reachable via the one of the second PE node and the multihome configuration.

Simplification of layer 2 VPLS control plane

Systems and methods for enhancing Segment Routing (SR) protocols are provided for enabling the stitching of a remote SR policy to a local SR policy. A method can include obtaining a Segment Routing (SR) policy for routing a packet along a path in a downstream domain, the SR policy including at least a destination field and a color field, the destination field defining an end-point of the path in the downstream domain, the end-point representing a destination node or service instance, the color field defining the path in the downstream domain, and storing the SR policy in the database.

Stitching a segment routing (SR) policy to a local SR policy for routing through a downstream SR domain

A node configured to operate in a network that operates one or more of Internet Protocol version 6 (IPv6) and Segment Routing over IPv6 (SRv6), the node comprising circuitry configured to receive a packet from another node in the network, wherein the node supports both a reduced mode and a non-reduced mode, and determine whether there is an identifier in the packet that indicates whether the packet is based on the reduced mode or the non-reduced mode. The identifier can be utilized to determine whether a destination address in the packet is either an IPv6 destination address or an SRv6 micro-Segment Identifier (uSID).

Distinguishing SRv6 micro-SID destination address from IPv6 destination address

Systems and methods associated with a node in a Segment Routing network include, responsive to what services are support at a node in a Segment Routing network, creating a bitmap to represent the plurality of services supported at the node; and transmitting an advertisement with the bitmap such that the advertisement is a single advertisement of multiple services. This approach can reduce the advertisement of rout updates by orders of magnitude.

Bitmap signaling of services using segment routing

Systems and methods include, in a node in a Segment Routing network, learning an adjacency Segment Identifier (SID) of a directly connected neighbor; and programming forwarding entries including a primary path and backup path associated with the adjacency SID. The programming is only performed for adjacency SIDs of directly connected neighbors, for use as a Point of Local Repair (PLR). This addresses holes in Topology Independent Loop Free Alternative (TI-LFA) node protection scheme for Segment Routing Traffic Engineering (SR-TE) paths.

Control plane based enhanced TI-LFA node protection scheme for SR-TE paths

A node in a segment routing version 6 (SRv6) network includes circuitry configured to transmit and receive packets in the SRv6 network with a segment routing header (SRH) that supports one or more of a Reduced mode and a Non-reduced mode, transmit via transmitted routing updates to one or more nodes in the SRv6 network which of the one or more of the Reduced mode and the Non-reduced mode are supported by the node, and receive via received routing updates from the one or more nodes their corresponding support for the one or more of the Reduced mode and the Non-reduced mode.

Distribution of SRv6 modes of operation via routing protocols

Systems and methods for Segment Routing Traffic Engineering (SR-TE) with awareness of local protection include the advertisement of local protection information in effect at each SR capable node via Interior Gateway Protocol (IGP), Border Gateway Protocol Link-State advertisement (BGP-LS), telemetry, etc. This information can include identity (IP address) of protected elements (link/node), type of protection (node, link, SRLG), a SID list for the backup path, whether protection is active, etc. This information can also be advertised via Path Computation Element Protocol (PCEP) as well. The information can also include a Binding SID (BSID) in the advertisement for local backup paths. Further, the present disclosure can enable a new SR OAM message (probe) to instruct a node to activate/deactivate a specific backup path in the forwarding plane for testing purposes.

Segment routing traffic engineering (SR-TE) with awareness of local protection

A node in a Segment Routing Internet Protocol version 6 (SRv6) network includes circuitry configured to, for a packet destined to a Service Function Chain (SFC), encode one or more micro-Segment Identifiers (uSIDs) for the SFC, wherein at least one uSID of the one or more uSIDs includes an Endpoint Behavior field, responsive to the at least one uSID needing one or more Arguments, include the one or more Arguments after the Endpoint Behavior field, and transmit the packet towards the SFC. The present disclosure presents various techniques to utilize uSIDs for SFC.

Service Function Chaining using uSID in SRv6

Systems and methods implemented in a network element in a Segment Routing network include, for a service having two or more candidate paths and responsive to a failure on a current candidate path of the two or more candidate paths, setting an eligibility flag for the current candidate path; and selecting another candidate path of the two or more candidate paths, for the service, based on their eligibility flag.

Emulating MPLS-TP behavior with non-revertive candidate paths in Segment Routing

Systems and methods for micro-loop avoidance include detecting a remote link failure in a network and identifying an associated Point of Local Repair (PLR); determining destinations in the network that are impacted due to the remote link failure; and installing of a temporary tunnel to the PLR. The steps can further include sending traffic destined for nodes impacted by the remote link failure via the temporary tunnel to the PLR. The temporary tunnel can be implemented by a node Segment Identifier (SID) for the PLR.

Micro-loop avoidance in networks

A Provider Edge (PE) node includes a plurality of ports including an inter-chassis port to a second PE node, a port connected to a root node, and one or more ports connected to leaf nodes, wherein the plurality of ports are in an Ethernet Tree (E-Tree), and wherein the root node is dual-homed to the PE node and the second PE node; switching circuitry configured to switch traffic between the plurality of ports; and circuitry configured to designate the inter-chassis port as one of a leaf node and a root node in the E-Tree instance, and manage a designation of the inter-chassis port based on a status of the port connected to the root node. The designation is changed in a data plane instead of in a control plane.

Fast convergence of E-Tree with a dual homed root node

A node configured to operate in a network that operates one or more of Internet Protocol version 6 (IPv6) and Segment Routing over IPv6 (SRv6), the node includes circuitry configured to determine a packet is to be sent to a second node in the network, with both the node and the second node utilizing Reduced Mode micro-Segment Identifiers (uSIDs), and include an identifier in an IPv6 header of the packet denoting a destination address of the packet includes uSIDs. The circuitry can be further configured to include the identifier responsive to a determination the second node supports the identifier.

Systems and methods for incrementally eliminating Border Gateway Protocol&#x2014;Labeled Unicast (BGP-LU) in a multi-region network include receiving BGP-LU updates from one or more Area Border Router (ABR) nodes in a multi-region network with the ABR nodes between two areas including a first area utilizing Segment Routing without utilizing BGP-LU and a second area utilizing BGP-LU; and, responsive to a request from a first node in the first area to reach a second node in the second area, providing a Segment Identifier (SID) list to the first node where the SID list is determined based on the Segment Routing in the first area and the BGP-LU updates from the second area.

Incrementally eliminating BGP-LU using SR policies and PCE

Systems and methods in a node in an MPLS network include determining a plurality of services supported at the node; determining a bitmask to represent the plurality of services supported at the node, wherein the bitmask includes a starting service and each subsequent bit representing another service of the plurality of services and with each bit in the bitmask set based on the plurality of services supported at the node; and transmitting an advertisement to other nodes in the network with the bitmask based on the plurality of services supported at the node. The steps can further include transmitting a packet associated with a service of the plurality of services with an MPLS label stack including one or more transport labels for a destination of the packet, a service label identifying the service, and a source label identifying a source Internet Protocol (IP) address of the packet.

Optimized L2/L3 services over classical MPLS transport

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Kanata, Canada

Muthurajah Sivabalan