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.

A network node receives a data packet. In response to receiving the data packet, the network node performs a lookup on a label stack of the data packet to determine a next hop for the data packet. The network node scans the label stack to identify a Structured Entropy Label (SEL). The SEL includes a Path Tracing Indicator (PTI). The network node computes Midpoint Compressed Data (MCD) as a result of the PTI being set to a pre-defined value. The network node records the MCD in a MCD stack of the data packet by shifting the MCD stack and stamping the MCD on top of the MCD stack. The network node transmits the data packet to the next hop with the recorded MCD stack. The network sink node encapsulates the received data packet to generate an encapsulated data packet and transmits the data packet.

Described herein are methods and devices (e.g., routers) that add network services to a multiprotocol label switching (MPLS) network. A method can include a network device of the MPLS network receiving a packet, the network device of the MPLS network modifying the packet by adding multiple MPLS extension headers, wherein each of the multiple MPLS extension headers added to the packet is used to support a different one of multiple network services for the MPLS network, and the network device of the MPLS network forwarding the packet as modified to another network device of the MPLS network.

In a connection-oriented network a point-to-multipoint working path is established between a source node and a plurality of destination nodes using a number of working path intermediate nodes. A point-to-multipoint protection path is established for possible points of failure in the working path. Each protection path connects a first working path intermediate node upstream of a point of failure and destination nodes of the working path downstream of the first working path intermediate node. The point-to-multipoint protection path only connects to destination nodes of the working path and working path intermediate nodes which must be transited to reach the destination nodes of the working path.

An apparatus and method for path creation element driven dynamic setup of forwarding adjacencies and explicit path. In one embodiment of the method, a node receives an instruction to create a tunnel between the node and another node. The node creates or initiates the creation of the tunnel in response to receiving the instruction, wherein the tunnel comprises a plurality of nodes in data communication between the node and the other node. The node maps a first identifier (ID) to information relating to the tunnel. The node advertises the first ID to other nodes in a network of nodes.

In one embodiment, a method includes identifying, by a router, a first tenant. The first tenant is associated with a first tenant virtual private network (VPN). The method also includes determining, by the router, a mapping of the first tenant VPN to a first device VPN and generating, by the router, a first label representing the first device VPN. The method further includes adding, by the router, the first label to a first network packet and communicating, by the router, the first network packet with the first label to a controller.

In general, techniques are described for reducing or otherwise preventing micro-loops in network using Source Packet Routing in Networking (SPRING). In some examples, a method includes detecting a failure of a communication by a network device that implements a Source Packet Routing in Networking (SPRING) protocol to forward network packets using node labels according to an initial network topology. Responsive to detecting the failure of the communication link, the network device may apply, for a defined time duration, one or more adjacency labels to network packets to define a set of one-hop tunnels corresponding to a backup sub-path that circumvents the failed communication link. Upon expiration of the defined time duration, the network device may forward, according to a new network topology that is not based on applying the one or more adjacency labels that define the set of one-hop tunnels, network packets destined for the destination network device.

The invention includes a method and apparatus for distributing flooding labels within a Multiprotocol Label Switching (MPLS) infrastructure supporting Border Gateway Protocol (BGP) Media Access Control (MAC) Virtual Private Networking (VPN).

The present disclosure provides for carrying downstream mapping information in an echo request message and/or echo reply message, which can describe both IP (Internet Protocol) multipath information and label multipath information. A transit node (e.g., an LSR element) that receives an echo request message from an initiator node determines downstream mapping information, which is returned to the initiator node. Transit node determines whether a newly defined type of multipath information (type 10) should be generated to return the downstream mapping information, based on whether transit node performs load balancing based on labels or IP header information, and whether transit node imposes entropy labels. A multipath information type 10 element includes either IP multipath information or label multipath information, as well as associated label multipath information that includes one or more entropy labels that map to the IP or label multipath information being returned.

Various example embodiments for supporting selection of a transport protocol for use in supporting a label distribution protocol in a label switching network are presented. Various example embodiments for supporting selection of a transport protocol for use in supporting a label distribution protocol in a label switching network may be configured to support multiple transport protocol options for use in supporting use of the label distribution protocol between a pair of label switched routers in the label switching network. Various example embodiments for supporting selection of a transport protocol for use in supporting a label distribution protocol in a label switching network may be configured to use the selected transport protocol to support various aspects of the label distribution protocol (e.g., establishment of a label distribution protocol session based on the label distribution protocol, label distribution based on the label distribution protocol, and so forth).