Abstract: In one example, a merge point network device (MP) receives a plurality of resource reservation request messages for establishing a plurality of label switched paths (LSPs), wherein each of the plurality of LSPs has a common point of local repair network device (PLR) and has the MP as a common MP, wherein each of the resource reservation request messages identifies a common bypass tunnel that extends between the PLR and the MP and avoids a protected resource. The MP stores an association between the bypass tunnel and each of the plurality of LSPs. The MP receives a single message to trigger creation at the merge point network device of backup LSP state information for all of the plurality of LSPs. In response to receiving the single message, the MP installs state information for all of the LSPs that correspond to the bypass tunnel according to the stored association.

Abstract: The disclosed computer-implemented method may include (1) receiving, at a network node within a network, a packet from another network node within the network, (2) identifying, within the packet, a label stack that includes a plurality of labels that collectively represent at least a portion of a label-switched path within the network, (3) popping, from the label stack, a label that corresponds to a next hop of the network node, (4) determining, based at least in part on the label, that the next hop has experienced a failure that prevents the packet from reaching a destination via the next hop, (5) identifying a backup path that merges with the label-switched path at a next-to-next hop included in the label-switched path, and then (6) forwarding the packet to the next-to-next hop via the backup path. Various other methods, systems, and apparatuses are also disclosed.

Abstract: In general, techniques described are for providing graceful restart procedures for network devices of label switched paths (LSPs) implemented with label stacks. For example, a restarting network device may include a processor coupled to a memory that executes software configured to: receive a path signaling message including a recovery object that defines a reverse path of the LSP from an egress network device of the LSP to the restarting network device, including at least an upstream label and a downstream label associated with the restarting network device; determine, based on the recovery object, the upstream label and the downstream label associated with the restarting network device; and instantiate a control plane state of the restarting network device based on the recovery object.

Abstract: A control device may subscribe to receive data from a network device. The data may be associated with a plurality of packets that have been dropped by the network device and include a first descriptor based on a type of packet drop associated with a packet of the plurality of packets that have been dropped by the network device, and one or more second descriptors based on a packet flow associated with the plurality of packets that have been dropped by the network device. The control device may determine a dropped packet profile associated with the network device, based on the first descriptor and the one or more second descriptors. The control device may generate a first notification based on the dropped packet profile associated with the network device and transmit the first notification to cause an action to be performed based on the first notification.

Abstract: The disclosed computer-implemented method may include (1) receiving, at a network node within a network, a packet from another network node within the network, (2) identifying, within the packet, a label stack that includes a plurality of labels that collectively represent at least a portion of a label-switched path within the network, (3) popping, from the label stack, a label that corresponds to a next hop of the network node, (4) determining, based at least in part on the label, that the next hop has experienced a failure that prevents the packet from reaching a destination via the next hop, (5) identifying a backup path that merges with the label-switched path at a next-to-next hop included in the label-switched path, and then (6) forwarding the packet to the next-to-next hop via the backup path. Various other methods, systems, and apparatuses are also disclosed.

Abstract: A device may identify a portion of a label-switched path (LSP) on which a simple hierarchical LSP (sH-LSP) is to be used for transferring traffic via a network. The device may determine attribute information associated with the sH-LSP. The attribute information may include information associated with one or more characteristics of the sH-LSP. The device may provide an indication associated with identifying an available sH-LSP or creating a sH-LSP. The indication may include the attribute information associated with the sH-LSP, and may be being provided to cause the sH-LSP to be created on the portion of the LSP or an available sH-LSP, associated with the portion of the LSP, to be identified. The device may receive, based on providing the indication, an identifier associated with the sH-LSP. The device may cause the LSP to be set up based on the identifier associated with the sH-LSP.

Abstract: The disclosed system may include (1) receiving, at an ingress node within a network, a request to forward a packet along a label-switched path to an egress node within the network, (2) identifying a limit on the number of labels that the ingress node is capable of forwarding within a label stack of the packet, (3) determining that the number of hops within the label-switched path exceeds the limit on the number of labels that the ingress node is capable of forwarding, (4) selecting at least one of the hops within the label-switched path to act as a delegation node that imposes, onto the label stack of the packet, at least one label corresponding to a downstream hop within the label-switched path and (5) forwarding the packet from the ingress node to the delegation node to enable the delegation node to impose the label onto the label stack.

Abstract: The disclosed computer-implemented method may include (1) receiving, at a network node within a network, a packet from another network node within the network, (2) identifying, within the packet, a label stack that includes a plurality of labels that collectively represent at least a portion of an LSP within the network, (3) popping, from the label stack, a label that corresponds to a specific link to a further network node, and then upon popping the label from the label stack, (4) forwarding the packet to the further network node by way of the specific link. Various other methods, systems, and apparatuses are also disclosed.

Abstract: Techniques are described for establishing lower priority LSPs on paths determined to be less likely to include bandwidth constrained links. In one example, a router includes a plurality of physical interfaces each having at least one link interconnecting the router as one of a plurality of routers in a network and a processor. The processor is configured to determine whether a link of one of the plurality of physical interfaces is congested based at least in part on an amount of available bandwidth on the link, and, responsive to determining that the link is congested, set a bandwidth subscription for the link, wherein the bandwidth subscription specifies that the amount of available bandwidth on the link for label switched paths having a lower priority is less than the amount of available bandwidth on the link for label switched paths having a higher priority.

Abstract: The disclosed computer-implemented method may include (1) receiving, at a network node within a network, a packet from another network node within the network, (2) identifying, within the packet, a label stack that includes a plurality of labels that collectively represent at least a portion of an LSP within the network, (3) popping, from the label stack, a label that corresponds to a specific link to a further network node, and then upon popping the label from the label stack, (4) forwarding the packet to the further network node by way of the specific link. Various other methods, systems, and apparatuses are also disclosed.

Abstract: Techniques are described for reusing downstream-assigned labels when establishing a new instance of a label switched path (LSP) prior to tearing down an existing instance of the LSP using make-before-break (MBB) procedures for RSVP. The techniques enable a routing engine of any non-ingress router along a path of the new LSP instance to reuse a previously allocated label for the existing LSP instance as the downstream assigned label for the new LSP instance when the paths of the existing LSP instance and the new LSP instance overlap. In this way, the non-ingress router does not need to update a label route in its forwarding plane for the reused label. When the new LSP instance completely overlaps the existing LSP instance, an ingress router of the LSP may avoid updating an ingress route in its forwarding plane for applications that use the LSP.

Abstract: In general, techniques described are for bandwidth sharing between resource reservation protocol label switched paths (LSPs) and non-resource reservation protocol LSPs. For example, in networks where resource reservation protocol LSPs and non-resource reservation protocol LSPs co-exist within the same domain, resource reservation protocol LSPs and non-resource reservation protocol LSPs may share link bandwidth. However, when non-resource reservation protocol LSPs are provisioned, resource reservation protocol path computation elements computing resource reservation protocol paths may not account for non-resource reservation protocol LSP bandwidth utilization. The techniques described herein provide a mechanism for automatically updating traffic engineering database (TED) information about resource reservation protocol LSPs in a way that accounts for non-resource reservation protocol LSP traffic flow statistics, such as bandwidth utilization.

Abstract: In general, the disclosure relates to techniques for initiating a targeted LDP session in a manner that includes information specifying one or more application for which a targeted LDP session is being initiated. In one example, a method includes receiving, by a network device, a LDP initialization message to initiate an Label Distribution Protocol (LDP) session with a peer network device, the LDP initialization message including a Targeted Applications Capability (TAC) field specifying one or more applications for which the LDP session is to be used for advertising forwarding equivalence class (FEC)-label bindings between the network device and the peer network device, and determining, by the network device, whether to allow the LDP session to be established based on the one or more applications specified in the TAC field.

Abstract: Techniques are described for specifying and constructing multi-protocol label switching (MPLS) rings. Routers may signal membership within MPLS rings and automatically establish ring-based label switch paths (LSPs) as components of the MPLS rings for packet transport within ring networks. In one example, a router includes a processor configured to output Label Distribution Protocol (LDP) messages, as described herein, to establish an MPLS ring having a plurality of ring LSPs. Each of the ring LSPs is configured to transport MPLS packets around the ring network to a different one of the routers operating as an egress router for the respective ring LSP. Moreover, each of the ring LSPs comprises two counter-rotating multipoint-to-point (MP2P) LSPs for which any of the routers can operate as an ingress to source packet traffic into the ring LSP for transport to the respective egress router for the ring LSP.

Abstract: The disclosed system may include (1) receiving, at an ingress node within a network, a request to forward a packet along a label-switched path to an egress node within the network, (2) identifying a limit on the number of labels that the ingress node is capable of forwarding within a label stack of the packet, (3) determining that the number of hops within the label-switched path exceeds the limit on the number of labels that the ingress node is capable of forwarding, (4) selecting at least one of the hops within the label-switched path to act as a delegation node that imposes, onto the label stack of the packet, at least one label corresponding to a downstream hop within the label-switched path and (5) forwarding the packet from the ingress node to the delegation node to enable the delegation node to impose the label onto the label stack.

Abstract: A network device receives configuration information defining one or more abstract hops for which membership is defined as those network devices that satisfy a logical combination of one or more constituent attributes. The network device determines based on network topology information, for each of the defined abstract hops, a set of network devices that qualify for membership in the abstract hop. The network device receives a request to establish a label switched path (LSP) from an ingress network device to an egress network device, wherein the request specifies, as a constraint for the LSP, a plurality of hops in a defined order, including the one or more abstract hops. The network device selects a path from the ingress network device to the specified egress network device based on the ordered abstract hop constraint, and establishes the LSP along the selected path according to the defined order of the request.

Abstract: In general, techniques are described for dynamically filtering, at area border routers (ABRs) of a multi-area autonomous system, routes to destinations external to an area by advertising to routers of the area only those routes associated with a destination address requested by at least one router of the area. In one example, a method includes receiving, by an ABR that borders a backbone area and a non-backbone area of a multi-area autonomous system that employs a hierarchical link state routing protocol to administratively group routers of the autonomous system into areas, a request message from the non-backbone area that requests the ABR to provide routing information associated with a service endpoint identifier (SEI) to the non-backbone area. The request message specifies the SEI. The method also includes sending, in response to receiving the request and by the ABR, the routing information associated with the SEI to the non-backbone area.

Abstract: The disclosed computer-implemented method may include (1) receiving, at a network node within a network, a packet from another network node within the network, (2) identifying, within the packet, a label stack that includes a plurality of labels that collectively represent at least a portion of an LSP within the network, (3) popping, from the label stack, a label that corresponds to a specific link to a further network node, and then upon popping the label from the label stack, (4) forwarding the packet to the further network node by way of the specific link. Various other methods, systems, and apparatuses are also disclosed.

Abstract: The disclosed computer-implemented method may include (1) receiving, at a network node within a network, a packet from another network node within the network, (2) identifying, within the packet, a label stack that includes a plurality of labels that collectively represent at least a portion of a label-switched path within the network, (3) popping, from the label stack, a label that corresponds to a next hop of the network node, (4) determining, based at least in part on the label, that the next hop has experienced a failure that prevents the packet from reaching a destination via the next hop, (5) identifying a backup path that merges with the label-switched path at a next-to-next hop included in the label-switched path, and then (6) forwarding the packet to the next-to-next hop via the backup path. Various other methods, systems, and apparatuses are also disclosed.

Abstract: The disclosed computer-implemented method for verifying the functionality of network paths may include (1) constructing, at a source node within a network, a test packet that uniquely identifies a network path whose functionality is unverified, (2) sending the test packet to a target node within the network via the network path in an attempt to verify the functionality of the network path, (3) receiving, back from the target node, the test packet sent to the target node via the network path, and then (4) verifying, at the source node, the functionality of the network path based at least in part on the test packet received back from the target node. Various other methods, systems, and computer-readable media are also disclosed.