Multicast based on penultimate hop popping

An apparatus, comprising:

• at least one processor;
• and
• at least one memory including program code;
• wherein the at least one memory and the program code are configured to, with the at least one processor, cause the apparatus to at least:
• determine a multicast tree for a multicast group, wherein the multicast tree includes a root router, a set of transit routers, and a set of leaf routers;
• and
• establish the multicast tree based on an indication that penultimate hop popping (PHP) is to be used on the multicast tree.

An apparatus, comprising:

• at least one processor;
• and
• at least one memory including program code;
• wherein the at least one memory and the program code are configured to, with the at least one processor, cause the apparatus to at least:
• determine, by a root router of a multicast tree, that penultimate hop popping (PHP) is to be used on the multicast tree;
• and
• send, by the root router toward a controller, an indication that PHP is to be used on the multicast tree.

An apparatus, comprising:

• at least one processor;
• and
• at least one memory including program code;
• wherein the at least one memory and the program code are configured to, with the at least one processor, cause the apparatus to at least:
• receive, by a penultimate hop (PH) router of a multicast tree, a multicast packet including a tree label identifying the multicast tree, an upstream assigned label, and a multicast payload;
• remove, by the PH router, the tree label from the multicast packet to form a modified multicast packet;
• and
• send, by the PH router toward one or more leaf routers of the multicast tree via the multicast tree, the modified multicast packet.

An apparatus, comprising:

• at least one processor;
• and
• at least one memory including program code;
• wherein the at least one memory and the program code are configured to, with the at least one processor, cause the apparatus to at least:
• receive, by a leaf router of a multicast tree from a penultimate hop router of the multicast tree, a multicast packet including a multicast payload and having an upstream assigned label as an outer label;
• and
• determine, by the leaf router based on the upstream assigned label and the multicast payload, forwarding of the multicast payload from the leaf router.