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: Particular embodiments described herein provide for a communication system that can be configured to identify a system that includes network traffic, where at least a portion of the network traffic includes packets, at least a portion of the packets include a stack, and at least a portion of each stack includes one or more previously allocated labels. The communication system can further be configured to determine a synonymous label that triggers an action and to replace a label from the one of the one or more previously allocated labels in a specific stack of a specific packet with the synonymous label. In an example, the synonymous label can be used to identify a subset of packets in the network traffic or a source of the specific packet.

Abstract: In one embodiment, primary circuits may be established on a network link, where each primary circuit individually allocates primary bandwidth of the network link and is assigned to one of either a respective primary weighted queue of the network link corresponding to a size of the respective primary circuit or a shared primary weighted queue of the network link corresponding to a total size of the individually allocated primary bandwidth for the network link. In addition, protection circuits may also be established on the network link, where the protection circuits collectively allocate shared backup bandwidth of the network link and are assigned to a shared backup weighted queue of the network link corresponding to a size of the shared backup bandwidth for the network link. As such, primary and backup packets may be forwarded on the network link according to the primary and backup weighted queues (e.g., allowing 1:1 protection).

Abstract: In one embodiment, a method includes generating at a network device, a continuity test packet configured to pass through a set of communication paths terminating at the network device and at least one other network device located at an opposite end of the communication paths, transmitting at the network device the continuity test packet on a first communication path in the set of communication paths, and identifying at the network device a failure in the set of communication paths if the continuity test packet is not received on a last communication path in the set of communication paths. An apparatus and logic are also disclosed herein.

Abstract: In one embodiment, a source transmits one or more data packets to a destination over a primary pseudowire (PW). When a device on the primary PW detects a downstream failure of the primary PW, and in response to receiving one or more data packets from a source from the failed primary PW, the device adds a loopback packet identifier to the one or more received data packets, and returns the one or more data packets with the loopback packet identifier to the source upstream on the primary PW. Accordingly, in response to receiving the data packet returned with a loopback packet identifier from the primary PW (in response to the downstream failure), the source retransmits the one or more data packets to the destination over a backup PW.

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: In one embodiment, an ingress router sends a multipath information query across a computer network toward an egress router, and builds an entropy table based on received query responses. The entropy table maps the egress router to one or more available paths to the egress router, and associated entropy information for each respective available path of the one or more available paths. The ingress router may then forward traffic to the egress router using the entropy table to load share the traffic across the one or more available paths using the associated entropy information for each respective available path. In response to detecting a failure of a particular path of the one or more available paths, however, the ingress router then removes the particular path from the entropy table, thereby ceasing forwarding of traffic over the particular path.

Abstract: In one embodiment, a method includes receiving at a node in a first network, information identifying a spare interface between a first network device in the first network and a second network device in a second network, and using the spare interface to create a path in the first network if the spare interface is compatible. The spare interface information includes connectivity and compatibility information.

Abstract: In one embodiment, a method includes generating at a network device, a continuity test packet configured to pass through a set of communication paths terminating at the network device and at least one other network device located at an opposite end of the communication paths, transmitting at the network device the continuity test packet on a first communication path in the set of communication paths, and identifying at the network device a failure in the set of communication paths if the continuity test packet is not received on a last communication path in the set of communication paths. An apparatus and logic are also disclosed herein.

Abstract: Particular embodiments described herein provide for a communication system that can be configured to identify a system that includes network traffic, where at least a portion of the network traffic includes packets, at least a portion of the packets include a stack, and at least a portion of each stack includes one or more previously allocated labels. The communication system can further be configured to determine a synonymous label that triggers an action and to replace a label from the one of the one or more previously allocated labels in a specific stack of a specific packet with the synonymous label. In an example, the synonymous label can be used to identify a subset of packets in the network traffic or a source of the specific packet.

Abstract: In one embodiment, a circuit that extends between a head-end label switching router (LSR) and a tail-end LSR and traverses one or more intermediate LSRs is locked to data plane traffic. The head-end LSR transmits a packet along the circuit that includes a particular time-to-live (TTL) value configured to expire at a particular intermediate LSR at which loopback is to occur. The circuit is used in a loopback mode. The head-end LSR transmits along the circuit a packet that includes a cease loopback request. The circuit ceases to be used in the loopback mode. The circuit is unlocked to permit the circuit to pass data plane traffic.

Abstract: A technique may improve LDP-IGP synchronization in a MPLS network when an interface of a router coupled to a communications link along a shortest path between a source router and a destination router becomes newly active. Specifically, an IGP adjacency may be held down over the newly active link while a LDP adjacency is established over the link. The router may inject a temporary, non-redistributable route having a large administrative weight into its routing table utilizing addresses learned during establishment of the LDP adjacency. The injected route ensures that there is a reachable route to a peer router so that LDP may converge. After LDP has converged and all needed label bindings have been distributed in the MPLS network utilizing the injected route, IGP executing on the router may advertise a normal cost metric for the link associated with the newly active interface, and IGP convergence may be completed.

Abstract: In one embodiment, an ingress router sends a multipath information query across a computer network toward an egress router, and builds an entropy table based on received query responses. The entropy table maps the egress router to one or more available paths to the egress router, and associated entropy information for each respective available path of the one or more available paths. The ingress router may then forward traffic to the egress router using the entropy table to load share the traffic across the one or more available paths using the associated entropy information for each respective available path. In response to detecting a failure of a particular path of the one or more available paths, however, the ingress router then removes the particular path from the entropy table, thereby ceasing forwarding of traffic over the particular path.

Abstract: The present disclosure provides for carrying downstream mapping information in an echo request message and/or echo reply message, which can describe both IP (Internet Protocol) multipath information and label multipath information. A transit node (e.g., an LSR element) that receives an echo request message from an initiator node determines downstream mapping information, which is returned to the initiator node. Transit node determines whether a newly defined type of multipath information (type 10) should be generated to return the downstream mapping information, based on whether transit node performs load balancing based on labels or IP header information, and whether transit node imposes entropy labels. A multipath information type 10 element includes either IP multipath information or label multipath information, as well as associated label multipath information that includes one or more entropy labels that map to the IP or label multipath information being returned.

Abstract: In one embodiment, a path computation element (PCE) in a computer network receives one or more path computation requests (PCReqs), and records a time of each PCReq and the corresponding requested bandwidth. Based on this information, the PCE may determine a traffic profile of the computer network, and may augment a traffic engineering database (TED) with requested bandwidth according to time based on the traffic profile. As such, prior to a particular time, the PCE may determine placement of tunnels within the traffic profile for the particular time.

Abstract: A technique may improve LDP-IGP synchronization in a MPLS network when an interface of a router coupled to a communications link along a shortest path between a source router and a destination router becomes newly active. Specifically, an IGP adjacency may be held down over the newly active link while a LDP adjacency is established over the link. The router may inject a temporary, non-redistributable route having a large administrative weight into its routing table utilizing addresses learned during establishment of the LDP adjacency. The injected route ensures that there is a reachable route to a peer router so that LDP may converge. After LDP has converged and all needed label bindings have been distributed in the MPLS network utilizing the injected route, IGP executing on the router may advertise a normal cost metric for the link associated with the newly active interface, and IGP convergence may be completed.

Abstract: In one embodiment, a method includes generating an aggregated pseudowire status message at a first network device in a Multi-Protocol Label Switching (MPLS) network, transmitting the aggregated pseudowire status message to a second network device on a Label Switched Path (LSP) extending between the first and second network devices in the MPLS network, and establishing at the first network device, an aggregated pseudowire status session with the second network device upon receiving a response to the aggregated pseudowire status message on the LSP. The aggregated pseudowire status message configured to verify a current status of pseudowires on the LSP. An apparatus is also disclosed.

Abstract: A technique may improve LDP-IGP synchronization in a MPLS network when an interface of a router coupled to a communications link along a shortest path between a source router and a destination router becomes newly active. Specifically, an IGP adjacency may be held down over the newly active link while a LDP adjacency is established over the link. The router may inject a temporary, non-redistributable route having a large administrative weight into its routing table utilizing addresses learned during establishment of the LDP adjacency. The injected route ensures that there is a reachable route to a peer router so that LDP may converge. After LDP has converged and all needed label bindings have been distributed in the MPLS network utilizing the injected route, IGP executing on the router may advertise a normal cost metric for the link associated with the newly active interface, and IGP convergence may be completed.

Abstract: In one embodiment, a router initiates reroutes of one or more tunnels at the router as part of optimization of a plurality of tunnels in a computer network, and stores an original state of the one or more tunnels at the router prior to the optimization. By detecting whether path computation element (PCE) failure occurs prior to completion of the optimization, the router may revert to the original state of the one or more tunnels in response to PCE failure prior to completion of the optimization.

Abstract: The present disclosure provides for carrying downstream mapping information in an echo request message and/or echo reply message, which can describe both IP (Internet Protocol) multipath information and label multipath information. A transit node (e.g., an LSR element) that receives an echo request message from an initiator node determines downstream mapping information, which is returned to the initiator node. Transit node determines whether a newly defined type of multipath information (type 10) should be generated to return the downstream mapping information, based on whether transit node performs load balancing based on labels or IP header information, and whether transit node imposes entropy labels. A multipath information type 10 element includes either IP multipath information or label multipath information, as well as associated label multipath information that includes one or more entropy labels that map to the IP or label multipath information being returned.