A method includes receiving, by a first device, first information from a network device, the first information being usable for activating or releasing semi-persistent scheduling (SPS) of a second device, and for indicating a first or second direction of the SPS. The first device sends second information to the second device, the second information being usable for activating or releasing the SPS of the second device. In the first direction, the second device receives data sent by the first device, and, in the second direction, the first device receives data sent by the second device.