| CPC H04L 1/08 (2013.01) [H04L 1/1812 (2013.01); H04W 72/20 (2023.01)] | 20 Claims |

|
1. A method, comprising:
determining, by a first terminal device, a value of a first new data indicator (NDI) using an identifier of a first destination address and an identifier of a first hybrid automatic repeat request (HARQ) process, wherein the first NDI is comprised in first sidelink control information (SCI), and the first SCI schedules first data; and
sending, by the first terminal device through a sidelink, the first SCI or the first data to a second terminal device.
|