Abstract: A communication method and an apparatus are provided. The method includes: a first node receives a resource scheduling message transmitted by an upper-level node. The resource scheduling message carries template identification information indicating a target time slot allocation template to be used. The first node determines a transmission time slot of the first node based on indication information that is included in the target time slot allocation template and that is used for allocating time slots to a plurality of nodes. Because a byte length occupied by the template identification information is far less than a byte length occupied by time slot allocation information corresponding to each node, a length of the resource scheduling message can be greatly shortened, and even if a quantity of nodes in the communication system increases, the length of the resource scheduling message does not increase.

Abstract: Embodiments of this application provide a data transmission method applied to power line communication, and a power line communication apparatus and system. The data transmission method includes: a power line node generates a data frame, where the data frame includes a first field, a second field, and a third field, the first field is used to carry a modulation parameter, the second field is used to carry, in a bit mapping manner, identification information that is of at least one destination node of current multicast and that is configured by the power line node, and the third field is used to carry service data; and the power line node sends the data frame to a node in a power line communication network. According to the data transmission method, data can be efficiently transmitted to a plurality of destination nodes to save bandwidth.