A wireless device receives a radio resource control (RRC) message comprising configuration parameters for uplink resources associated with a small data transmission (SDT) procedure of the wireless device. The wireless device transmits, to a base station central unit (BS-CU) via the uplink resources of a base station distributed unit (BS-DU), an RRC resume request message for the SDT procedure, and uplink data associated with the SDT procedure. The wireless device receives, from the BS-CU to via the BS-DU, an RRC release message after the BS-CU receives a message indicating inactivity notification and completion of the SDT procedure.