Communication method and apparatus

A method for communication, wherein the method comprises:

• obtaining, by a second node, a first packet, wherein the first packet comprises multicast routing information of the second node, a multicast routing identifier of a node is used by a non-leaf child node of the node in a multicast tree to determine multicast routing information of the non-leaf child node, and multicast routing information of a node comprises a multicast routing identifier of the node and multicast routing information of a non-leaf child node of the node in the multicast tree;
• and
• sending, by the second node, the first packet to a first node, wherein the first node is a child node of the second node in the multicast tree.

A first node, wherein the first node comprises at least one processor and one or more memories coupled to the at least one processor, wherein the one or more memories store programming instructions for execution by the at least one processor to perform operations comprising:

• receiving a first packet from a second node, wherein the first packet comprises multicast routing information of the second node, the first node is a child node of the second node in a multicast tree, a multicast routing identifier of a node is used by a non-leaf child node of the node in the multicast tree to determine multicast routing information of the non-leaf child node, and multicast routing information of a node comprises a multicast routing identifier of the node and multicast routing information of a non-leaf child node of the node in the multicast tree;
• and
• parsing the first packet.