Abstract: Techniques are described for class-based traffic engineering in an IP network. For example, routers of an IP network may establish one or more constrained traffic engineered paths using a link-state protocol (e.g., IGP) without using signaling protocols, such as RSVP or SPRING, or encapsulating packets over MPLS. For example, an egress router of the IP network may receive a capability message specifying the capability of routers to compute a constrained path to the egress router, wherein the capability message comprises path computation information including an identifier of a path computation algorithm to be used by the one or more of the plurality of network devices to reach the egress network device. The egress router may advertise a reachability message including a destination IP prefix and the identifier of the path computation algorithm to cause routers in the IP network to compute the constrained path to reach the egress router.

Abstract: In general, techniques are described for signaling IP path tunnels for traffic engineering using constraints in an IP network. For example, network devices, e.g., routers, of an IP network may compute an IP path using constraint information and establish the IP path using, for example, Resource Reservation Protocol, to signal the IP path without using MPLS. As one example, the egress router generates a path reservation signaling message that includes an egress IP address that is assigned for use by the routers on the IP path to send traffic of the data flow by encapsulating the traffic with the egress IP address and forwarding toward the egress router. As each router in the IP path receives the path reservation signaling message, the router configures a forwarding state to forward traffic encapsulated with the egress IP address to a next hop along the IP path toward the egress router.

Abstract: A method is described and in one embodiment includes receiving a packet of a traffic flow at an ingress node of a communications network; routing the packet to an egress node of the communications network via a first path comprising a tunnel if the packet was received from a node external to the communications network; and routing the packet to the egress node of the communications network via a second path that does not traverse the tunnel if the packet was received from a node internal to the communications network. The first path is identified by a first Forwarding Information Base (“FIB”) entry corresponding to the flow and the second path is identified by a second FIB entry corresponding to the flow.

Abstract: A display control device includes: a turn signal installed in a vehicle; indicators for displaying a lighting state of the turn signal to an occupant of the vehicle; and a controller for controlling the lighting state of the turn signal and a lighting state of the indicators. The controller makes timing of starting to turn on the turn signal and timing of starting to turn on the indicators different from each other.

Abstract: The present technology is directed to a scalable solution for end-to-end performance delay measurement for Segment Routing Policies on both SR-MPLS and SRv6 data planes. The scalability of the solution stems from the use of distributed PM sessions along SR Policy ECMP paths. This is achieved by dividing the SR policy into smaller sections comprised of SPT trees or sub-paths, each of which is associated with a Root-Node. Downstream SID List TLVs may be used in Probe query messages for signaling SPT information to the Root-Nodes Alternatively, this SPT signaling may be accomplished by using a centralized controller. Root-Nodes are responsible for dynamically creating PM sessions and measuring delay metrics for their associated SPT tree section. The root-nodes then send the delay metrics for their local section to an ingress PE node or to a centralized controller using delay metric TLV field of the response message.

Abstract: The present technology is directed to a scalable solution for end-to-end performance delay measurement for Segment Routing Policies on both SR-MPLS and SRv6 data planes. The scalability of the solution stems from the use of distributed PM sessions along SR Policy ECMP paths. This is achieved by dividing the SR policy into smaller sections comprised of SPT trees or sub-paths, each of which is associated with a Root-Node. Downstream SID List TLVs may be used in Probe query messages for signaling SPT information to the Root-Nodes Alternatively, this SPT signaling may be accomplished by using a centralized controller. Root-Nodes are responsible for dynamically creating PM sessions and measuring delay metrics for their associated SPT tree section. The root-nodes then send the delay metrics for their local section to an ingress PE node or to a centralized controller using delay metric TLV field of the response message.

Abstract: In one embodiment, a device in a network determines that traffic sent via a first label switched path should be sent via a new label switched path. The device sends the traffic along the new label switched path using a label stack that indicates one or more adjacency segments or interface binding labels. A particular node along the new label switched path is configured to forward the traffic via a particular interface of the node based on a corresponding interface binding label or adjacency segment indicated by the traffic. The device completes a switchover from the first path to the new path.

Abstract: The present technology is directed to a scalable solution for end-to-end performance delay measurement for Segment Routing Policies on both SR-MPLS and SRv6 data planes. The scalability of the solution stems from the use of distributed PM sessions along SR Policy ECMP paths. This is achieved by dividing the SR policy into smaller sections comprised of SPT trees or sub-paths, each of which is associated with a Root-Node. Downstream SID List TLVs may be used in Probe query messages for signaling SPT information to the Root-Nodes Alternatively, this SPT signaling may be accomplished by using a centralized controller. Root-Nodes are responsible for dynamically creating PM sessions and measuring delay metrics for their associated SPT tree section. The root-nodes then send the delay metrics for their local section to an ingress PE node or to a centralized controller using delay metric TLV field of the response message.

Abstract: A method is described and in one embodiment includes receiving a packet of a traffic flow at an ingress node of a communications network; routing the packet to an egress node of the communications network via a first path comprising a tunnel if the packet was received from a node external to the communications network; and routing the packet to the egress node of the communications network via a second path that does not traverse the tunnel if the packet was received from a node internal to the communications network. The first path is identified by a first Forwarding Information Base (“FIB”) entry corresponding to the flow and the second path is identified by a second FIB entry corresponding to the flow.

Abstract: The present technology is directed to a scalable solution for end-to-end performance delay measurement for Segment Routing Policies on both SR-MPLS and SRv6 data planes. The scalability of the solution stems from the use of distributed PM sessions along SR Policy ECMP paths. This is achieved by dividing the SR policy into smaller sections comprised of SPT trees or sub-paths, each of which is associated with a Root-Node. Downstream SID List TLVs may be used in Probe query messages for signaling SPT information to the Root-Nodes Alternatively, this SPT signaling may be accomplished by using a centralized controller. Root-Nodes are responsible for dynamically creating PM sessions and measuring delay metrics for their associated SPT tree section. The root-nodes then send the delay metrics for their local section to an ingress PE node or to a centralized controller using delay metric TLV field of the response message.

Abstract: A method is described and in one embodiment includes receiving a packet of a traffic flow at an ingress node of a communications network; routing the packet to an egress node of the communications network via a first path comprising a tunnel if the packet was received from a node external to the communications network; and routing the packet to the egress node of the communications network via a second path that does not traverse the tunnel if the packet was received from a node internal to the communications network. The first path is identified by a first Forwarding Information Base (“FIB”) entry corresponding to the flow and the second path is identified by a second FIB entry corresponding to the flow.

Abstract: Utilizing the systems disclosed herein, a network element (in a network) controls, within another network, the constraints of a service, timing of the creation of the service, and selection a service on which a packet is transmitted. For example, a first network element (located in a first network) receives a request associated with initiating a service. The request is received from a second network element located in a second network and includes at least one path constraint. The first network element controls creation of the service in the first network on behalf of the second network element located in the second network by, e.g., identifying a path based, at least in part, on the at least one path constraint; and binding an identifier and an interface to the path, wherein the interface is associated with one or more operation to perform on any traffic that is labeled with the identifier.

Abstract: In one embodiment, a device in a segment routed network identifies an adjacency segment between the device and another device in the network. The device also identifies a merge point in the network. A first network path extends between the device and the merge point via the adjacency segment. A bypass network path that does not include the adjacency segment also extends between the device and the merge point. The device generates an interior gateway protocol (IGP) message that identifies the adjacency segment and the merge point. The device provides the IGP message to one or more other devices in the network.

Abstract: A method is described and in one embodiment includes receiving a packet of a traffic flow at an ingress node of a communications network; routing the packet to an egress node of the communications network via a first path comprising a tunnel if the packet was received from a node external to the communications network; and routing the packet to the egress node of the communications network via a second path that does not traverse the tunnel if the packet was received from a node internal to the communications network. The first path is identified by a first Forwarding Information Base (“FIB”) entry corresponding to the flow and the second path is identified by a second FIB entry corresponding to the flow.

Abstract: In one embodiment, a device in a network determines that traffic sent via a first label switched path should be sent via a new label switched path. The device sends the traffic along the new label switched path using a label stack that indicates one or more adjacency segments or interface binding labels. A particular node along the new label switched path is configured to forward the traffic via a particular interface of the node based on a corresponding interface binding label or adjacency segment indicated by the traffic. The device completes a switchover from the first path to the new path.

Abstract: Utilizing the systems disclosed herein, a network element (in a network) controls, within another network, the constraints of a service, timing of the creation of the service, and selection a service on which a packet is transmitted. For example, a first network element (located in a first network) receives a request associated with initiating a service. The request is received from a second network element located in a second network and includes at least one path constraint. The first network element controls creation of the service in the first network on behalf of the second network element located in the second network by, e.g., identifying a path based, at least in part, on the at least one path constraint; and binding an identifier and an interface to the path, wherein the interface is associated with one or more operation to perform on any traffic that is labeled with the identifier.

Abstract: An example method for seamless path monitoring and rapid fault isolation using bidirectional forwarding detection (BFD) in a network environment is provided and includes determining a BFD target identifier type for communicating in a BFD session in a network environment, determining a non-zero globally assigned BFD discriminator value associated with the BFD target identifier type, populating a Your Discriminator field in a BFD Control Packet with the non-zero globally assigned BFD discriminator value, with a My Discriminator field in the BFD Control Packet being populated with a locally assigned BFD Discriminator value, and initiating the BFD session by transmitting the BFD Control Packet to a target node in the network. In a specific embodiment, the BFD target identifier type is type 3, and the non-zero globally assigned BFD discriminator is an Alert Discriminator reserved by substantially all nodes in the network exclusively for BFD traceroute operations.

Abstract: In one embodiment, a node in a communication network receives a label switched path (LSP) request and in response, the node determines at least two equal cost paths, each path having one or more path-nodes. The node may then further determine a total bandwidth-based transition value for each path of the at least two equal cost paths and selects the path having a lower total transition value. Once selected, the node may establish the requested LSP over the selected path.

Abstract: At a first network device, a plurality of paths through a network from a source network device to a destination network device are determined. A vacant bandwidth is calculated for each of the plurality of paths. A primary path is selected from the plurality of paths based on the vacant bandwidth, and a standby path is selected from the plurality of paths based on the vacant bandwidth.

Abstract: In one embodiment, a device in a segment routed network identifies an adjacency segment between the device and another device in the network. The device also identifies a merge point in the network. A first network path extends between the device and the merge point via the adjacency segment. A bypass network path that does not include the adjacency segment also extends between the device and the merge point. The device generates an interior gateway protocol (IGP) message that identifies the adjacency segment and the merge point. The device provides the IGP message to one or more other devices in the network.