With reference to the third aspect, in a sixth possible implementation of the third aspect, that the determining unit determines the M resources according to the N available resources after an interval of preset duration T includes randomly selecting the M resources from the N available resources, or obtaining L resources according to the N available resources, and randomly selecting, by the first UE, the M resources from the L available resources.
With reference to the third aspect, in a seventh possible implementation of the third aspect, that the determining unit obtains L resources according to the N available resources specifically includes obtaining the L resources after performing an operation on the N available resources by using a preset rule.
With reference to the third aspect, in an eighth possible implementation of the third aspect, the data sent by the sending unit to the at least one UE is new data obtained after original data is discarded, or is the original data.