In accordance with an embodiment, a communication method applied to a first node includes: receiving first information from a second node, wherein the first information comprises an available space size in a first buffer space of the second node, the first buffer space is for buffering a data packet that is to be transmitted through a first path, the first path is a primary path for transmitting the data packet, and the second node is a next-hop node of the first node on the primary path; and in response to the available space size in the first buffer space being less than or equal to a first threshold, determining to transmit the data packet through a third node, wherein the third node is a next-hop node of the first node on a backup path for transmitting the data packet.