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: 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: 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 are described for a path computation delay timer for multi-protocol label switched networks. As an example, an ingress network device configured to act as an ingress for a label switched path (LSP) may perform the techniques. The ingress network device comprises an interface and a processor. The interface may receive a message indicating an error along the LSP. The processor may delay an operation performed to configure a replacement LSP to be used in place of the LSP in order to provide time during which a cause of the error along the LSP is able to be determined. When the cause of the error is determined to be a failure of a network device supporting operation of the LSP, the processor may further perform the operation to configure the replacement LSP with the ingress network device such that the replacement LSP avoids the failed network device.

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: Techniques for reducing the latency in performing a failover from a protected connection to its backup connection when a network event is detected affecting the protected connection. In an MPLS network, techniques are provided for failing a protected LSP to a backup LSP in a fast and efficient manner. In one embodiment, the faster failover is facilitated by storing protected LSPs and their backup LSPs information in the data plane, such as locally on a linecard.

Abstract: In one example, a method includes establishing a plurality of label switched paths (LSPs) having a common transit network device other than an ingress network device or an egress network device of any of the plurality of LSPs, and, by the transit network device along the plurality of LSPs, detecting a congestion condition on a link along the plurality of LSPs and coupled to the transit network device. The method also includes, responsive to detecting the congestion condition, and by the transit network device, selecting a subset of the plurality of LSPs to evict from the link, wherein the subset comprises less than all of the plurality of LSPs, and updating a forwarding plane of the transit network device to reroute network traffic received for the selected subset of the plurality of the LSPs for forwarding to a next hop on a bypass LSP that avoids the link.

Abstract: Techniques for reducing the latency in performing a failover from a protected connection to its backup connection when a network event is detected affecting the protected connection. In an MPLS network, techniques are provided for failing a protected LSP to a backup LSP in a fast and efficient manner. In one embodiment, the faster failover is facilitated by storing protected LSPs and their backup LSPs information in the data plane, such as locally on a linecard.