Techniques are described for reporting, by non-ingress routers for traffic engineering label switched paths (TE LSPs) and to a path computation element, actual paths taken by the TE LSPs through the network. A first network device: receives, from a second network device, an LSP path signaling message that includes a route object having a first indication of at least a sub-path of a path for TE LSP through a network, wherein the first network device is not an ingress label edge router for the TE LSP; generates, in response to the LSP path signaling message and based at least in part on the route object, an LSP path report message that includes a second indication of the at least the sub-path of the path for the TE LSP; and sends, to a path computation element, the LSP path report message to notify the PCE.

In general, techniques are described for providing Hot-Root Standby in Global Table Multicast (GTM) environments. For example, in such GTM environments, normally a single unicast route to the customer multicast source (“C-Source”) will be available to egress provider edge (PE) routers. As described herein, ingress PE routers may advertise multiple routes to a C-Source, including unicast routes that include Route Import Extended Communities, which are imported by egress PE routers. This enables an egress PE router to have multiple paths to the C-Source, and the egress PE router may generate multiple C-multicast source tree joins for respective ingress PE routers in order to receive respective multicast streams sourced by the C-Source from the ingress PE routers.

Techniques are described for avoiding traffic black-holing in a multi-homed Ethernet virtual private networks (EVPNs) in which a customer device (CE) is multi-homed to a plurality of multi-homing provider edge devices (PEs) via respective links of an Ethernet segment. An overlay network is created over the Ethernet segment, and the multi-homing PEs of the EVPN are configured with a common anycast IP address for respective virtual network interfaces. Upon election as active designated forwarder (DF) for the EVPN, the DF PE of the multi-homing PEs advertises toward the customer network an IGP metric for the anycast IP address that is lower than the IGP metric(s) advertised by any of the non-DF standby PE routers segment to direct the CE to forward network packets from the customer network to the DF PE over the respective link of the Ethernet segment.

Embodiments of the present disclosure are directed to augmenting a Network Service Header (NSH) metadata of a data packet with a virtual routing and forwarding identifier (VRF-ID) and forgoing augmenting a virtual private network (VPN) label into a multiprotocol label switched (MPLS) metadata of the data packet. A provider edge router can use the VRF-ID to identify a next hop for the data packet as a service to be applied prior to forwarding the data packet to a VPN site.

A path computation element (PCE) central controller (PCECC) comprising a memory comprising executable instructions and a processor coupled to the memory and configured to execute the instructions. Executing the instructions causes the processor to receive a request to compute a path through a network, the request comprising a plurality of computational tasks, divide the computational tasks into a plurality of groups of computational tasks, transmit at least some of the plurality of groups of computational tasks to a plurality of path computation clients (PCCs) for computation by the PCCs, and receive, from the PCCs, computation results corresponding to the plurality of groups of computational tasks.

In one embodiment, a system includes a number of application-specific integrated circuits (ASICs). The system also includes one or more processors coupled to the ASICs including instructions executable by the processors. The processors being operable when executing the instructions to configure the plurality of ASICs to route data packets using a standard protocol; configure the ASICs to set up a tunnel, using the standard protocol, for moving data packets from one ASIC to another of the number of ASICs; and implement a software overlay to facilitate interaction between the number of ASICs through the tunnel for moving the data packets.

In general, techniques are described for configuring a provider edge (PE) network device of an Ethernet virtual private network (EVPN) to use a common traffic engineering label (e.g., MPLS label) for different EVPN route types associated with the same EVPN. In some examples, the techniques include sending a first layer three (L3) control plane message that indicates a label-switched network protocol label that corresponds to a first EVPN route type, wherein the first L3 control plane message indicates that a first PE network device is reachable in the L2 segment. The techniques may include performing L2 address learning to determine at least one L2 address associated with the layer two segment of the EVPN. The techniques may include sending a second L3 control plane message that indicates the same label included in the first L3 control plane message corresponds to a second EVPN route type.

Techniques are described for providing fast re-route (FRR) node and/or link protection along a primary label switched path (LSP) using generic routing encapsulation (GRE) over multi-protocol label switching (MPLS). An ingress edge router of a primary LSP is configured to encapsulate incoming packets into GRE with a destination address of an egress edge router of the primary LSP, and push a primary label onto the encapsulated packet for forwarding along the primary LSP. Upon a failover to a bypass LSP, a point of local repair (PLR) router swaps the primary label on the encapsulated packet with a bypass label. A merge point (MP) router then receives the encapsulated packet via the bypass LSP, and performs a lookup using the destination address of the egress edge router included on the encapsulated packet in order to determine a primary label for forwarding the encapsulated packet along the primary LSP.

This infrastructure includes a network MPLS; first and second groups of access points associated with each section of the track; first and second modems, on the train, communicating with access points of the first and second groups. The network includes pairs of local switches, each associated with a section of the track and including first and second local switches for communication with, respectively, the first and second groups of access points of the associated section, and first and second central switches, the switches being in series with one another and implementing a service for defining paths between each central switch and each local switch so the path between the first central switch and the first local switch of a pair and the path between the second central switch and the second local switch of this pair correspond to separate portions of the ring formed by the network.

The disclosed computer-implemented method for forwarding network traffic using minimal Forwarding Information Bases (FIBS) may include (1) identifying a Routing Information Base (RIB) that includes a set of routes that define paths to destinations both inside and outside a network and then (2) creating a FIB that includes a subset of active routes whose size is below a size threshold by (A) importing, from the set of routes within the RIB, (I) internal routes that define paths to destinations inside the network, (II) high-traffic external routes that define paths to destinations outside the network, and (III) a default route that defines a path to a default node that facilitates resolution of traffic that does not match any of the internal or high-traffic external routes and (B) excluding, from the FIB, low-traffic external routes that define paths to destinations outside the network. Various other methods, systems, and apparatuses are also disclosed.