Abstract: A method is implemented by a first Provider Edge (PE) network device in a network to configure a pseudo-wire (PW) between the first PE network device and a second PE network device in the network using Intermediate System to Intermediate System (IS-IS). The method includes receiving a first LSP update flooded in the network by the second PE network device via IS-IS, where the first LSP update advertises the PW. The method further includes configuring a local forwarding information base with a local PW label associated with the PW such that the first PE network device forwards traffic encapsulated with the local PW label to an Attachment Circuit associated with the PW and flooding a second LSP update in the network via IS-IS that includes an indication that the first PE network device is ready to receive traffic from the second PE network device over the PW.

Abstract: Methods and apparatuses for enabling sub-seconds link failure detection in a multi-chassis link aggregation group (MC-LAG) system are described. A first network device of a packet network transmits a Multiprotocol Label Switching (MPLS) encapsulated packet over a first link that is part of the MC-LAG, where the MC-LAG couples the first network device with a second network device and a third network device and the second and third network devices are part of an inter-chassis redundancy (ICR) system. The MPLS encapsulated packet includes a generic associated channel header (ACH) and a payload, and where the payload includes a bidirectional forwarding detection (BFD) control packet.

Abstract: A computer-implemented method of discrepancy detection by a configuration server is provided that comprises: receiving, by one or more processors of the configuration server, a request to compare a first management datastore with a second management datastore; comparing, by the one or more processors of the configuration server, the first management datastore with the second management datastore to identify differences; and in response to the request, sending over a network, by the one or more processors of the configuration server, the differences.

Abstract: Methods and apparatuses for enabling sub-seconds link failure detection in a multi-chassis link aggregation group (MC-LAG) system are described. A first network device of a packet network transmits an IP packet over a first link that is part of the MC-LAG, where the MC-LAG couples the first network device with a second network device and a third network device and the second and third network devices are part of an Inter-Chassis Redundancy (ICR) system. The IP packet includes a payload including a Bidirectional Forwarding Detection (BFD) control packet, where the destination address of the IP packet is one of a multicast IP address and a broadcast IP address.

Abstract: A router operates in both a Segment Routing (SR) network portion and a Multiprotocol Label Switching (MPLS) network portion of a network that utilizes Open Shortest Path First (OSPF). The router receives an OSPF advertisement message originated by a mapping server that includes a sub-Type-length-value (sub-TLV) element that identifies a preferred type of path across the MPLS network portion for an identifiable set of traffic that is to be received by the router from the SR network portion. The router identifies, based at least in part upon the sub-TLV element, one path of a plurality of available paths across the MPLS network portion for the identifiable set of traffic, and configures its forwarding plane to utilize the identified one path accordingly for the identifiable set of traffic. The OSPF advertisement message can be an OSPF LSA, and can carry an Extended Prefix Range TLV including the sub-TLV element.

Abstract: A method is implemented by a node for enabling shortest path bridging in a network that is scalable to support sixteen million virtual local area network (VLAN) identifiers using multiprotocol label switching (MPLS) encapsulation. The method comprises allocating a tunnel label using a distributed tunnel label allocation algorithm, allocating a source label using a distributed source label allocation algorithm, assigning a bridge instance a service label, and distributing the tunnel label, source label and service label to other nodes in the MPLS network.

Abstract: A provider edge (PE) router and methods for establishing a pseudowire using open shortest path first (OSPF) link state advertisement (LSA) messages. The pseudowire links the PE router with a remote PE router through a packet switched network (PSN), and emulates other communications protocols to provide customer edge (CE) equipment connected to the PE routers the appearance of a dedicated private circuit.

Abstract: A method is implemented by a network device to establish a bidirectional forwarding detection (BFD) session with a defined return path to enable detection of data plane failures between an active node and a passive node in a network where a forward path and a reverse path between the active node and the passive node are not co-routed. The method includes receiving a label switched path (LSP) ping including a BFD discriminator type length value (TLV) of the active node and a return path TLV describing a return path to the active node. The BFD discriminator of the active node and a BFD discriminator of the passive node are associated with the BFD session. The return path is associated with the BFD session between the active node and the passive node, and BFD control packets are sent to the active node using the return path to detect a failure on the return path.

Abstract: A method implemented by a network device acting as a border gateway protocol (BGP) speaker, of exposing a maximum segment identifier depth (MSD) value of the network device is described. The method comprises encoding the MSD value into a BGP Link State (BGP-LS) extension message. The BGP-LS extension message includes a type, a length and a MSD value. The type indicates the type of the MSD value, the length indicates the length of the MSD value and the MSD value indicates a lowest MSD value supported by the network device for enabling segment routing. The method continues with transmitting the BGP-LS extension message including the type, the length, and the MSD value to a network controller, where the network controller is to use the MSD value to compute a segment routing path including the network device.

Abstract: A method is implemented by a network device to establish a bidirectional forwarding detection (BFD) session with a defined return path to enable detection of data plane failures between an active node and a passive node in a network where a forward path and a reverse path between the active node and the passive node are not co-routed. The method includes receiving a label switched path (LSP) ping including a BFD discriminator type length value (TLV) of the active node and a return path TLV describing a return path to the active node. The BFD discriminator of the active node and a BFD discriminator of the passive node are associated with the BFD session. The return path is associated with the BFD session between the active node and the passive node, and BFD control packets are sent to the active node using the return path to detect a failure on the return path.

Abstract: A method implemented by a network device acting as a border gateway protocol (BGP) speaker, of exposing a maximum segment identifier depth (MSD) value of the network device is described. The method comprises encoding the MSD value into a BGP Link State (BGP-LS) extension message. The BGP-LS extension message includes a type, a length and a MSD value. The type indicates the type of the MSD value, the length indicates the length of the MSD value and the MSD value indicates a lowest MSD value supported by the network device for enabling segment routing. The method continues with transmitting the BGP-LS extension message including the type, the length, and the MSD value to a network controller, where the network controller is to use the MSD value to compute a segment routing path including the network device.

Abstract: A system and method for chaining one or more services in a service provider network. A service chaining policy and associated Service Path Identifier (SPID) are determined at an ingress node with respect to a particular data packet flow. If the service chaining policy involves one or more service nodes to be traversed by the data packet flow, each service node's EIDs and RLOCs are determined. A sequential data exchange process with the service nodes is effectuated using encapsulation of data packets based on the EIDs and RLOCs for obtaining services in accordance with the order of services set forth in the chaining policy.

Abstract: Exemplary methods include a first network device participating in an election process to determine a designated bit forwarding router (D-BFR). The methods include in response to determining the first network device is elected to be the D-BFR, performing D-BFR operations comprising assigning one or more bitmask positions (BMPs) to one or more bit forwarding egress routers (BFERs) and advertising the assigned one or more BMPs. The method may further include one or more of determining an elected bitmask (BM) length based on maximum local BM lengths advertised by other BFRs and determining an elected tree type based on supported tree types advertised by other BFRs.

Abstract: A method implemented by a first network device of enabling detection of a failure of a network device acting as a master of a virtual router redundancy protocol (VRRP) group of network devices is disclosed. The method comprises determining whether a first priority associated with the first network device is the highest priority when it is compared with priorities respectively associated with other network devices of the VRRP group. Responsive to determining that the first priority of the first network device is the highest priority, the method continues with causing the first network device to assume a master role in the VRRP group, and establishing a multipoint bidirectional forwarding detection (BFD) head session, wherein the BFD head session indicates that the first network device is action as a head of a multipoint BFD tree.

Abstract: Exemplary methods include a first network device participating in an election process to determine a designated bit forwarding router (D-BFR). The methods include in response to determining the first network device is elected to be the D-BFR, performing D-BFR operations comprising determining an elected bitmask (BM) length of a BM based on maximum local BM lengths advertised by other BFRs in the network, wherein each bit of the BM will correspond to a bit forwarding egress router (BFER), and advertising the determined elected BM length to other BFRs. The methods may further include one or more of determining an elected tree type based on supported tree types advertised by other BFRs in the network, assigning one or more BM positions (BMPs) to one or more BFERs, and advertising the elected determined tree type and/or the assigned one or more BMPs.

Abstract: A network device executes a method to forward a packet that is encoded using an explicit list encoding of sparse multicast group membership information with Bit Index Explicit Replication. The method includes receiving a packet that includes a bitstring having a list of Bit Forwarding Router IDs (BFR-ids). The method further includes selecting a BFR-id identifying a destination Bit Forwarding Router (BFR) from the list for processing, looking up a forwarding bitmask for the destination BFR and a next-hop to reach the destination BFR in a bit index forwarding table, creating a copy of the packet, clearing the selected BFR-id from the packet, clearing BFR-ids from the packet and the copy of the packet based on the forwarding bitmask, and forwarding the copy of the packet to the next-hop neighbor.

Abstract: A method performed by a network node. The method includes detecting a loss of connection at an incoming interface to an upstream neighbor of the network node, where the network node is in a multicast communication network that includes a multicast tree to provide connectivity from a common source node to one or more multicast recipient nodes. The multicast communication network further includes a set of one or more secondary paths to provide redundancy to the multicast tree, and sending a notification packet downstream toward the one or more multicast recipient nodes when the network node cannot re-route the multicast data traffic to allow the multicast data traffic to be received by the multicast recipient nodes, wherein the notification packet causes one or more downstream nodes to switch multicast reception to one or more of the set of one or more secondary paths to re-route the multicast data traffic.

Abstract: A system and method for chaining one or more services in a service provider network. A service chaining policy and associated Service Path Identifier (SPID) are determined at an ingress node with respect to a particular data packet flow. If the service chaining policy involves one or more service nodes to be traversed by the data packet flow, each service node's EIDs and RLOCs are determined. A sequential data exchange process with the service nodes is effectuated using encapsulation of data packets based on the EIDs and RLOCs for obtaining services in accordance with the order of services set forth in the chaining policy.

Abstract: A system and method for chaining one or more services in a service provider network. A service chaining policy and associated Service Path Identifier (SPID) are determined at an ingress node with respect to a particular data packet flow. If the service chaining policy involves one or more service nodes to be traversed by the data packet flow, each service node's EIDs and RLOCs are determined. A sequential data exchange process with the service nodes is effectuated using encapsulation of data packets based on the EIDs and RLOCs for obtaining services in accordance with the order of services set forth in the chaining policy.

Abstract: A method is disclosed that is implemented by a router for executing an internet protocol fast reroute process in response to a network event invalidating a current route to a destination node without degrading forwarding plane functionality or performance caused by indirect forwarding information base lookups. The method comprises a set steps including receiving or generating the network event by the router, the network event associated with a network event identifier and looking up the network event identifier in an event table to determine routes that are affected by the network event. The method further includes determining whether a route with a fast reroute forwarding object is affected by the network event in the routing information base and overwriting a current next hop forwarding object using a backup next hop forwarding object in the forwarding information base.