Abstract: Systems and methods for providing layer 1 services over a Segment Routing (SR) network include maintaining a Flexible Algorithm Definition (FAD) for Layer 1 services with the FAD across the SR network; receiving a request for a Layer 1 service and determining a Segment Identifier (SID) label stack based on the advertised FAD; and providing the Layer 1 service using the determined SID label stack.

Abstract: Systems and methods include maintaining a network plane in Segment Routing (SR) Flexible Algorithm having a Flexible Algorithm Definition (FAD) based on latency; receiving a request for a service over a SR network where the service is sensitive to a specific latency; and determining a label stack including one or more Segment Identifiers (SID) for the service, with the one or more SIDs based on the network plane in SR Flexible Algorithm. This can be used for Private Line Emulation (PLE) services and Circuit Emulation (CEM) services over SR, ensuring latency while not requiring large label stacks.

Abstract: Systems and methods for dynamic path computation in networks based on automatically detected unavoidable risks include receiving a plurality of shared risks associated with any of one or more network layers, network links, and network equipment; automatically creating a local ignore list for a source node and a remote ignore list for a destination node, based on the plurality of shared risks; and utilizing the plurality of shared risks in a path computation for a path between the source node and the destination node and ignoring any of the plurality of shared risks in the local ignore list and the remote ignore list.

Abstract: Systems and methods for an extended shortest path first computation for anycast prefix segments using a preferred metric-type include receiving an Interior Gateway Protocol (IGP) update with anycast group information therein; creating or updating a record for an anycast group with the anycast group information; computing a route for the anycast group based on a preferred metric associated with the anycast group information; and installing the computed route. The preferred metric can be specifically defined in the anycast group information.

Abstract: Systems and methods for zero touch configuration for a mesh of nodes using Segment Routing Flexible Algorithm define a Flex Algo Definition (FAD) of an auto-mesh plane. A method, in one embodiment, includes, responsive to the FAD, providing an advertisement of a Prefix Segment Identifier (SID) for a node in the auto-mesh plane; and including a flag in the advertisement designating whether the node is a destination node or a non-destination node in the auto-mesh plane. The destination node is one which requires transport connectivity to all other destination nodes in the auto-mesh plane, and the non-destination node is one used for reachability to all the destination nodes.

Abstract: Systems and methods include maintaining a network plane in Segment Routing (SR) Flexible Algorithm having a Flexible Algorithm Definition (FAD) based on latency; receiving a request for a service over a SR network where the service is sensitive to a specific latency; and determining a label stack including one or more Segment Identifiers (SID) for the service, with the one or more SIDs based on the network plane in SR Flexible Algorithm. This can be used for Private Line Emulation (PLE) services and Circuit Emulation (CEM) services over SR, ensuring latency while not requiring large label stacks.

Abstract: Systems and methods for dynamic path computation in networks based on automatically detected unavoidable risks include receiving a plurality of shared risks associated with any of one or more network layers, network links, and network equipment; automatically creating a local ignore list for a source node and a remote ignore list for a destination node, based on the plurality of shared risks; and utilizing the plurality of shared risks in a path computation for a path between the source node and the destination node and ignoring any of the plurality of shared risks in the local ignore list and the remote ignore list.

Abstract: Systems and methods for extended protection in a Segment Routing network that utilizes Flexible Algorithm include defining a first Flexible Algorithm that segregates the Segment Routing network into a first subset network that excludes any of links and nodes from the Segment Routing network; defining a second Flexible Algorithm that segregates the Segment Routing network into a second subset network, different from the first subset network; and defining extended protection for the first Flexible Algorithm with the second Flexible Algorithm whereby the second Flexible Algorithm is usable for path to protect the first Flexible Algorithm.

Abstract: In one embodiment, a technique enables protection, e.g., Fast Reroute (FRR) protection, for selective traffic in an area of a computer network. A source node, located at an edge or perimeter of a network area or located in the core of the network area, may utilize one of a plurality of labels when forwarding traffic to a destination node, wherein a first label (“a protected label”) indicates that traffic receive FRR protection and a second label (“an unprotected label”) indicates that that traffic not receive FRR protection.

Abstract: In one embodiment, certain SRLGs associated with members of a bundle are deemed to be “risk-free SRLGs”, i.e., SRLGs whose failure may not substantially impact the capacity of the bundle to carry traffic in a computer network. In a bandwidth unaware embodiment a number of active members of the bundle is identified for each SRLG, and a bandwidth aware embodiment further specifies an available bandwidth capacity for each SRLG to determine risk-free SRLGs. A backup path or tunnel may be established and utilized to protect a communication link as long as the SRLGs shared are deemed to be risk-free SRLGs.

Abstract: In one embodiment, certain SRLGs associated with members of a bundle are deemed to be “risk-free SRLGs”, i.e., SRLGs whose failure may not substantially impact the capacity of the bundle to carry traffic in a computer network. In a bandwidth unaware embodiment a number of active members of the bundle is identified for each SRLG, and a bandwidth aware embodiment further specifies an available bandwidth capacity for each SRLG to determine risk-free SRLGs. A backup path or tunnel may be established and utilized to protect a communication link as long as the SRLGs shared are deemed to be risk-free SRLGs.

Abstract: A technique for breaking a loop caused by looping alternate paths associated with a prefix in a communications network. One or more non-looping alternate paths associated with the prefix that exclude a first node in the communications network are identified. One or more alternate paths from nodes in the loop that are associated with the prefix are identified. An identified path that intersects with an identified non-looping path is established as an alternate path associated with the prefix at a node in the loop.

Abstract: A method and apparatus method for providing fast rerouting in a network is presented. The method and apparatus assign a first local label for a prefix, and assign a second local label for the prefix. The first local label is advertised to an upstream peer and the second local label is advertised to a downstream peer. A forwarding entry from the first local label for a prefix is switched to the second local label for the prefix when a failure of a link or next hop is detected.

Abstract: A method and apparatus method for providing fast rerouting in a network is presented. The method and apparatus assign a first local label for a prefix, and assign a second local label for the prefix. The first local label is advertised to an upstream peer and the second local label is advertised to a downstream peer. A forwarding entry from the first local label for a prefix is switched to the second local label for the prefix when a failure of a link or next hop is detected.