Enhancements to PIM fast re-route with upstream activation packets

A network node in a multicast communication network that includes a multicast tree and a set of secondary paths that are computed prior to failure in the multicast tree, the set of secondary paths provide redundancy to the multicast tree such that multicast data traffic is to be re-routed to one or more of the secondary paths in case of a failure in the multicast tree, the network node comprising:

• memory configured to store forwarding information for the multicast data traffic;
• receiver circuitry configured to receive an indication of a loss of connection to a primary path of the multicast tree that provides a path between the network node and a common source node;
• one or more processors coupled to the memory, the receiver circuitry and the transmitter circuitry, the one or more processors configured to
• determine whether the network node has a failure-free secondary path to the common source node, wherein the failure-free secondary path is computed prior to the loss of connection to the primary path and the failure-free secondary path includes a merge node with an unblocked incoming interface to the failure-free secondary path and a branch node with a blocked outgoing interface to the failure-free secondary path so that the multicast data traffic does not flow on the failure-free secondary path when there is no failure in the multicast communication network to reduce bandwidth usage,
• the one or more processors further configured to execute an upstream activation module to originate an activation packet in response to a determination that the network node has the failure-free secondary path;
• and
• transmitter circuitry coupled to the one or more processors and configured to send the activation packet upstream toward the common source node via the failure-free secondary path, wherein the activation packet causes an upstream node to unblock an outgoing interface to thereby activate transmission of the multicast data traffic on the failure-free secondary path.