Abstract: In some cases, once Fast Reroute (FRR) has taken place (e.g., for MPLS protection), a further FRR is undesirable, and even detrimental. A mechanism to prevent a further FRR, once such a further FRR is determined to be potentially harmful, is described.

Abstract: In some cases, once Fast Reroute (FRR) has taken place (e.g., for MPLS protection), a further FRR is undesirable, and even detrimental. A mechanism to prevent a further FRR, once such a further FRR is determined to be potentially harmful, is described.

Abstract: An example computing device is configured to receive, from a customer device, an indication of a plurality of resources and an indication of a plurality of customer services, each of the plurality of customer services being associated with a corresponding at least one requirement and a corresponding at least one constraint. The computing device is configured to automatically determine, for each requirement and each constraint, whether the requirement or the constraint can only be satisfied by a particular resource of the plurality of resources, and allocate, based on the determining, at least one resource of the plurality of resources to at least one customer service of the plurality of customer services. The example computing device is configured to provide, to the customer device and subsequent to the determining for every requirement and for every constraint, information to enable the customer device to provision the at least one customer service.

Abstract: Techniques are described for managing a plurality of requests for a change in bandwidth for a resource reservation label switched path (“LSP”) of a ring network. For example, a method may include receiving, by a network device and from an egress network device of a ring network, a resource reservation request message to establish a multipoint-to-point (MP2P) ring label switched path (LSP). The method may also include modifying, by the network device, the resource reservation request message to specify a request for a change in bandwidth for a segment from the network device to the egress network device of the MP2P ring LSP. The method may also include sending, by the network device and to a downstream network device along the MP2P ring LSP, the modified resource reservation request message.

Abstract: A ring node N belonging to a resilient MPLS ring (RMR) provisions and/or configures clockwise (CW) and anti-clockwise (AC) paths on the RMR by: (a) configuring two ring node segment identifiers (Ring-SIDs) on the ring node, wherein a first of the two Ring-SIDs (CW-Ring-SID) is to reach N in a clockwise direction on the ring and a second of the two Ring-SIDs (AC-Ring-SID) is to reach N in an anti-clockwise direction on the ring, and wherein the CW-Ring-SID and AC-Ring-SID are unique within a source packet routing in networking (SPRING) domain including the ring; (b) generating a message including the ring node's CW-Ring-SID and AC-Ring-SID; and (c) advertising the message, via an interior gateway protocol, for receipt by other ring nodes belonging to the ring such that (1) a clockwise multipoint-to-point path (CWP) is defined such that every other one of the ring nodes belonging to the ring can be an ingress for the CWP and such that only the node is an egress for the CWP, and (2) an anti-clockwise multipoint-

Abstract: This disclosure describes techniques relating to assigning unique segment identifiers (SIDs) in a segment routing network. In one example, this disclosure describes a method that includes receiving, by a computing system and from a node on a network, a request to allocate a segment identifier for use in a segment routing network; allocating, by the computing system and from a block of addresses, an assigned segment identifier; responding to the request by outputting, by the computing system and over the network to the node, information about the assigned segment identifier; and maintaining the assigned segment identifier.

Abstract: A ring node N belonging to a resilient MPLS ring (RMR) provisions and/or configures clockwise (CW) and anti-clockwise (AC) paths on the RMR by: (a) configuring two ring node segment identifiers (Ring-SIDs) on the ring node, wherein a first of the two Ring-SIDs (CW-Ring-SID) is to reach N in a clockwise direction on the ring and a second of the two Ring-SIDs (AC-Ring-SID) is to reach N in an anti-clockwise direction on the ring, and wherein the CW-Ring-SID and AC-Ring-SID are unique within a source packet routing in networking (SPRING) domain including the ring; (b) generating a message including the ring node's CW-Ring-SID and AC-Ring-SID; and (c) advertising the message, via an interior gateway protocol, for receipt by other ring nodes belonging to the ring such that (1) a clockwise multipoint-to-point path (CWP) is defined such that every other one of the ring nodes belonging to the ring can be an ingress for the CWP and such that only the node is an egress for the CWP, and (2) an anti-clockwise multipoint-

Abstract: In some cases, once Fast Reroute (FRR) has taken place (e.g., for MPLS protection), a further FRR is undesirable, and even detrimental. A mechanism to prevent a further FRR, once such a further FRR is determined to be potentially harmful, is described.

Abstract: A ring node N belonging to a resilient MPLS ring (RMR) provisions and/or configures clockwise (CW) and anti-clockwise (AC) paths on the RMR by: (a) configuring two ring node segment identifiers (Ring-SIDs) on the ring node, wherein a first of the two Ring-SIDs (CW-Ring-SID) is to reach N in a clockwise direction on the ring and a second of the two Ring-SIDs (AC- Ring-SID) is to reach N in an anti-clockwise direction on the ring, and wherein the CW-Ring-SID and AC- Ring-SID are unique within a source packet routing in networking (SPRING) domain including the ring; (b) generating a message including the ring node's CW-Ring-SID and AC-Ring-SID; and (c) advertising the message, via an interior gateway protocol, for receipt by other ring nodes belonging to the ring such that (1) a clockwise multipoint-to-point path (CWP) is defined such that every other one of the ring nodes belonging to the ring can be an ingress for the CWP and such that only the node is an egress for the CWP, and (2) an anti-clockwise multipoin

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 detecting egress network devices of a point-to-multipoint (P2MP) label switched path (LSP). For example, a network device may include one or more processors configured to identify a P2MP LSP for receiving multicast traffic from a multicast source for a specific multicast group for which the network device has an interested receiver, wherein the network device is to be an egress network device of the P2MP LSP; and send, to an ingress network device of the P2MP LSP, a P2MP egress identification message to add the network device as an egress network device of the P2MP LSP, wherein the one or more processors are further configured to output the P2MP egress identification message into a multipoint-to-point (MP2P) ring LSP for which the ingress network device of the P2MP LSP is a sole egress network device of the MP2P ring LSP.

Abstract: Techniques are described for detecting egress network devices of a point-to-multipoint (P2MP) label switched path (LSP). For example, a network device may include one or more processors configured to identify a P2MP LSP for receiving multicast traffic from a multicast source for a specific multicast group for which the network device has an interested receiver, wherein the network device is to be an egress network device of the P2MP LSP; and send, to an ingress network device of the P2MP LSP, a P2MP egress identification message to add the network device as an egress network device of the P2MP LSP, wherein the one or more processors are further configured to output the P2MP egress identification message into a multipoint-to-point (MP2P) ring LSP for which the ingress network device of the P2MP LSP is a sole egress network device of the MP2P ring LSP.

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 detecting egress network devices of a point-to-multipoint (P2MP) label switched path (LSP). For example, a network device may include one or more processors configured to identify a P2MP LSP for receiving multicast traffic from a multicast source for a specific multicast group for which the network device has an interested receiver, wherein the network device is to be an egress network device of the P2MP LSP; and send, to an ingress network device of the P2MP LSP, a P2MP egress identification message to add the network device as an egress network device of the P2MP LSP, wherein the one or more processors are further configured to output the P2MP egress identification message into a multipoint-to-point (MP2P) ring LSP for which the ingress network device of the P2MP LSP is a sole egress network device of the MP2P ring LSP.

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 liveness of routing protocols can be determined using a mechanism to aggregate liveness information for the protocols. The ability of an interface to send and receive packets and the forwarding capability of an interface can also be determined using this mechanism. Since liveness information for multiple protocols, the liveness of interfaces, the forwarding capability of interfaces, or both, may be aggregated in a message, the message can be sent more often than could individual messages for each of the multiple protocols. This allows fast detection of failures, and sending connectivity messages for the individual protocols, such as neighbor “hellos,” to be sent less often.

Abstract: Techniques are described for varying a bandwidth constraint at one or more hops along a path of a sub-label-switched path (sub-LSP) of a multi-path label-switched path (MP-LSP). The techniques include computing, by an ingress router, a plurality of paths for a plurality of sub-LSPs of a MP-LSP and outputting, by the ingress router, for each path of the plurality of paths, a respective resource reservation request message to establish a respective sub-LSP of the plurality of sub-LSPs, each respective resource reservation request message including an indication of an explicit route, a tunnel identifier indicating the MP-LSP, an identifier for the respective sub-LSP, an indication of a per-hop bandwidth constraint that corresponds to a respective incoming per-hop bandwidth constraint of the plurality of incoming per-hop bandwidth constraints, and one or more instructions to modify the indication of the per-hop bandwidth constraint.

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 liveness of routing protocols can be determined using a mechanism to aggregate liveness information for the protocols. The ability of an interface to send and receive packets and the forwarding capability of an interface can also be determined using this mechanism. Since liveness information for multiple protocols, the liveness of interfaces, the forwarding capability of interfaces, or both, may be aggregated in a message, the message can be sent more often than could individual messages for each of the multiple protocols. This allows fast detection of failures, and sending connectivity messages for the individual protocols, such as neighbor “hellos,” to be sent less often.

Abstract: A method performed by a network device may include assembling a multiprotocol label switching (MPLS) echo request, the echo request including an instruction for a transit node to forward the echo request via a bypass path associated with the transit node, and an instruction for an egress node to send an echo reply indicating that the echo request was received on the bypass path. The method may also include sending the MPLS echo request over a functioning label switched path (LSP).