A computer-readable storage medium stores instructions for execution by one or more processors of a UE. The instructions configure the UE for small data transmission (SDT) in a 5G NR network and cause the UE to perform operations comprising detecting while in an RRC_Inactive state, a radio link failure during a first SDT of UL data to a base station. A secure key for a second SDT is generated based on the radio link failure. A configuration message including an indication of the second SDT is transmitted to the base station. A response message including a UL grant is received from the base station. The UL data is encoded for the second SDT using the secure key. The second SDT is performed using the UL grant while the UE is in the RRC_Inactive state.